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Teaching IFR Flight Operations

INTEGRATED FLIGHT INSTRUCTION

"Integrated flight instruction" is flight instruction during which students are taught to perform flight maneuvers both by outside visual references and by reference to flight instruments, FROM THE FIRST TIME EACH MANEUVER IS INTRODUCED. No distinction in the pilot’s operation of the flight controls is permitted, regardless of whether outside references or instrument indications are used for the performance of the maneuver. When this training technique is used, instruction in the control of an airplane by outside visual references is "integrated" with instruction in the use of flight instrument indications for the same operations.

Integrated flight instruction was introduced on a national scale in 1959, when an amendment to the Civil Air Regulations established certain instruction and competency in the use of flight instruments as prerequisites for the issuance of private pilot certificates. The objective of this training was, and still is, the formation of firm habit patterns for the observance of and reliance on flight instruments from the student’s first piloting experience. Such habits have been proved to produce more capable and safer pilots for the efficient operation of today’s airplanes. The ability to fly in instrument weather is not the objective of this type of primary training, although it does greatly facilitate later instrument flight training.

DEVELOPMENT OF HABIT PATTERNS

General aviation accident reports provide ample support for the belief that habitual reference to flight instruments is important to safety. The safety record of pilots who hold instrument ratings is significantly better than that of pilots with comparable flight time who have never received formal instrument flight training. Student pilots who have been required to perform all normal flight maneuvers by reference to instruments, as well as by outside references, will develop from the start the habit of continuously monitoring their own and the airplane’s performance.

This habit would be much more difficult for a student to develop after intense piloting experience without it, as veteran pilots who begin formal training for an instrument rating can readily testify.

ACCURACY OF FLIGHT CONTROL

The greatest benefit of using the integrated method of fight instruction during pilot training is that students are more precise in their performance of maneuvers by visual references. This applies to all flight operations, not just when flight by reference to instruments is required. Notable among students achievements are better monitoring of power settings and more accurate maintenance of desired headings, altitudes, and airspeeds. As the habit of monitoring their own performance by reference to instruments is developed, students will begin to make corrections without prompting. The habitual attention to instrument indications leads to superior cross-country navigation, better coordination, improved landings because of more accurate airspeed control, and a generally better overall pilot competency.

EMERGENCY CAPABILITY

The use of integrated flight instruction helps develop the student's ability to maintain proper control of an airplane in flight for limited periods if outside references are lost. It also presents the instructor with an opportunity to introduce the dangers of spatial disorientation. Impress upon your student through demonstrations in flight that total reliance on flight instrument cross check and interpretation is essential to avoiding disaster. This ability could save the pilot’s life and those of the passengers in an actual emergency.

During the conduct of integrated flight training, the flight instructor must emphasize to the students that their introduction to the use of flight instruments does not prepare them for intentional operations in marginal or instrument weather conditions. The possible consequences, both to themselves and to others, of experiments with flight operations in weather conditions worse than those required for VFR operations before they are instrument rated, should be constantly impressed on the students.

PROCEDURES

The conduct of integrated flight instruction is simple. The use of an airplane equipped with flight instruments and an easily demountable means of simulating instrument flight conditions, such as an extended visor cap, are needed. The student’s first briefing on the function of the flight controls should include the instrument indications to be expected, as well as the outside references which should be used to control the attitude of the airplane.

Each new flight maneuver should be introduced using either outside references or instrument indications, as the instructor prefers. Then the student’s visor should be raised or lowered, whichever is appropriate, and the same maneuver performed again, this time by the use of the other set of references. This practice should continue throughout the student’s instruction for all flight maneuvers except those which require the use of ground references. To fully achieve the benefits of this type of training, the use of visual and instrument references must be constantly integrated throughout the training.

PRECAUTIONS

During the conduct of integrated flight instruction, the instructor must be especially vigilant for other air traffic while the student is operating under the hood by instrument references. The instructor must guard against having attention diverted to the student's performance for extended periods. Utilizing radar traffic advisories during training will enhance safety. Remember though, that traffic advisories are provided on a work load permitting basis and that radar does not pick up every traffic conflict. The responsibility for collision avoidance remains with the instructor even when radar advisories are being provided.

It is important to note that integrated instruction is not without it's critics. There are pilots both within and outside the FAA that worry that students will develop poor collision avoidance techniques by spending too much time referring to the instrument panel and not enough time looking for traffic. Also of concern is the possibility that the student may conclude that he (or she) has developed sufficient instrument flight skills to tackle limited visual conditions or even instrument weather. This is a valid concern and can not be ignored by the instructor.

Students quickly learn that it is easier to control aircraft performance by concentrating on the instrument panel. Not only does this validate the concerns mentioned above, but it also makes ground reference maneuvers more difficult for the student to perform. The instructor should carefully observe the student’s performance of maneuvers during the early stages of integrated flight instruction to assure that this habit does not develop. If it is detected, the instructor should make the student concentrate on maneuvering by outside references with the gyroscopic instruments caged or covered.

Of course, collision avoidance too, must be continually stressed. We all know that most mid air collisions occur in VFR weather conditions. The pilots involved in these collisions may not have been searching for other traffic. Teach your student to always ask for radar traffic advisories but to keep in mind that collision avoidance is always the responsibility of the pilot, as stated above.

During the conduct of integrated flight instruction the instructor should make it clear that the use of instruments is being taught to prepare students to accurately monitor their own and their airplane’s performance, not to qualify them for IFR operations. The instructor must avoid any indication, by word or action, that the proficiency sought is intended solely for use in difficult weather situations.

It is essential that a flight instructor be thoroughly familiar with the functions, characteristics, and proper use of all standard flight instruments. It is also the personal responsibility of each flight instructor to maintain familiarity with current pilot training techniques and certification requirements. This may be done by constant use of new periodicals and technical publications, personal contacts with Federal Aviation Administration Inspectors and designated pilot examiners, and by participation in pilot and flight instructor symposiums and clinics. The application of outmoded instructional procedures, or the preparation of student pilots using obsolete certification requirements is inexcusable.

INSTRUMENT FLYING TECHNIQUES (single pilot operations)

At this point in your career you have heard almost every thing there is to say about teaching instrument flying techniques. This presentation though will introduce you to concepts often over looked in IFR training programs.

How many times have you said, or heard another instrument instructor say, "Fly the airplane first, then worry about your position, and when that is all under control, talk to ATC." The phrase "Aviate, Navigate, and Communicate" comes to mind. But do you actually perform this way when you have an airplane full of passengers or freight in hard IFR? One of the biggest challenges for any talented instructor is correctly analyzing his or her own behavior when performing a task successfully and then developing that behavior in the student. Frequently you hear CFIs arguing vehemently about what controls altitude; is it pitch or power? Or what controls airspeed, pitch or power? What controls heading? Is it aileron or the rudder? Someone once asked Barry Bonds what his secret was in blasting the ball out of the park so many times. "Heck", he said, "I don't know. I just swing at the ball!"

Is it possible the CFI doesn't always know what factors are contributing to his or her performance and decision making? Many CFIs pass along the same advice they received from their instructor. However, the question to be answered is whether or not the CFI is actually following that advice himself! After all, a proficient pilot usually reacts to situations instinctively and subconsciously. The brain processes information and determines appropriate reactions at the speed of light. It is very possible the instructor thinks he or she is flying the way they were taught when actually pursuing a different course of action without realizing it. This is what happens when a student learns in spite of the instruction instead of because of it. When that student advances to become an instructor, he will probably teach the same way he was taught even though he has subconsciously found a different and more effective method to use.

So, back to the original question: Is Aviate, Navigate, and Communicate really effective? Maybe not! Perhaps Aviate, Aviate, and Aviate and then Aviate some more is more efficacious. Stop and think about it. Is there any such thing as single pilot IFR for the airlines? Of course the answer is NO! But why? Because whoever is flying the aircraft, whether it be the PIC or SIC, flying the aircraft is all they are doing. The pilot flying does not change frequencies on his radio. He doesn't even set the OBS! He doesn't put the gear down or up. He doesn't change the flap setting. He doesn't even talk to ATC! The pilot not flying is the one who handles these chores. The pilot flying may have 20,000 hours in his log book. He may be flying 1,000 hours a year. He might be adding another 200 hours of actual instrument time to his log book every year. And what has he learned from all this experience? The one thing he knows for sure is that you can not fly instruments, in hard IFR, unless you are looking at the instruments! He watches those six flight instruments like a hawk watches its prey. Any distraction is ignored or delegated to someone else.

But what about the weekend pilot who flies without the aid of a copilot? Can single pilot IFR be as safe as an airline operation with two pilots? Of course it can. Otherwise the FAA would not allow it. However, in order to ensure the highest level of safety during single pilot IFR operations, the pilot must learn to never stop being the PIC in order to accomplish SIC duties. Put another way, he cannot stop being the "pilot flying" in order to perform the duties of the "pilot not flying". He needs to work smarter not harder.

One well known and respected CFII suggests the pilot must learn how to fly the aircraft so well that he can do it instinctively and without conscious thought while concentrating on all the other duties imposed by instrument flight. Though the concept may seem sound, the implication is that the pilot's flying skill must somehow reach a level where he no longer needs to concentrate on controlling the aircraft.

It just doesn't work that way. Even with a sophisticated autopilot or FMS, the duties of flying or managing flight are enough to require the pilot's full and complete attention. How then is he to accomplish the other tasks? They are the items that must become no-brainers so as to not distract from flying the aircraft. Additionally, he needs to get assistance from whatever resources might exist, including ATC. That is what this discussion is all about.

STACKING THE DECK

The pilot can and must "stack the cards in his favor" during any flight, but especially during single pilot IFR operations.

Investigations into accidents occurring during IFR operations reveal the following as factors that increase risk:

1. IFR operations into unfamiliar airports (referred to as strange field let downs) during low IFR weather or at night.
2. Circling to land maneuvers during low IFR weather or at night.
3. Using unfamiliar cockpit automation.

It would therefore follow that a pilot who wishes to "stack the cards in his favor" will avoid strange field let downs during low IFR weather or at night, avoid circling to land maneuvers in those conditions, and not use cockpit automation with which he is unfamiliar. Requesting radar monitoring of the final approach is another tactic that will increase safety. In a two pilot crew, the pilot not flying provides a second set of eyes to monitor the approach. In a single pilot operation, ATC radar can do the job.

Advance planning, though, is the first and perhaps the most important step, in "stacking the deck". Teach your student to avoid surprises. Through advance planning, most decisions can be made ahead of time resulting in a more relaxed and confident flight. The pilot should be proactive instead of reactive. This includes showing your student how to seek advice from FSS or ATC or local area pilots regarding the clearance most likely to be issued for this trip. Then the pilot can mentally "pre fly" the trip and anticipate any complex maneuvering or navigation setups. If an FTD or PCATD is available, suggest that your student utilize it to "pre fly" the more complicated segments of the trip.

ATIS

ATIS was designed to help the pilot determine ahead of time (more advance planning) how the arrival will be accomplished. As you know, repetitive, important, but non-controlling information is provided on a separate frequency allowing the pilot to listen to a clear channel without being distracted by communications on the controllers frequency. It also reduces frequency congestion by removing this information from the controllers frequency. However, as with many great ideas, it works better on paper than in practice especially for single pilot IFR operations. When the pilot flying is the only pilot in the cockpit, he or she can not ignore the controller in order to copy the ATIS. So can this chore be accomplished while continuing to fly the aircraft?

First, lets look at what doesn't work! Some CFIs tell their students to monitor both freqs simultaneously. These instructors were taught that method while they were students and apparently have forgotten that it never worked very well. Only an unusually gifted individual can successfully listen to, and comprehend, two different conversations at the same time. 

Try this method; it is far more efficacious: Teach your student to anticipate a position approximately 15 minutes prior to where the change to Approach control might occur. That is a good place to call the current controller and tell ATC that you are switching to ATIS and will call him when you are back on his frequency. ATC will respond in one of two ways. The controller might say; "Frequency change approved. Call me when you are back on my frequency." This allows the pilot to listen to just the ATIS and will facilitate acquiring the necessary data quickly. The other response might be; "Negative! I will be handing you off to Approach control shortly. Make your request with the next controller." At first, this may seem counter productive. The procedure is to get the ATIS before calling Approach. Remember, though, you are preparing your student for single pilot operations and procedures must be modified accordingly. Simply instruct your student to contact Approach Control with the aircraft identification and altitude followed by the phrase, "Negative ATIS". Approach will then respond in one of two ways. ATC might say, "Current weather is... etc., etc., providing your student with the appropriate information negating the need to check ATIS or he or she might say; "Information Alpha (or Bravo or whatever) is current."  Request frequency change to pick up the ATIS information and report back on frequency after you have obtained it.

STRANGE FIELD LET DOWNS

Advance planning includes teaching your student to avoid "strange field letdowns". Handing your student an approach chart during a flight lesson and announcing, "Lets try this one", is unfair and unrealistic. It won't happen that way in the real world and shouldn't happen that way in training. Tell the student, at least a day before the lesson, what approaches will be flown during the lesson so he can study the charts ahead of time. Even suggest he try "pre flying" the approaches in an FTD or on a PCATD. The fact the time can not be logged is not relevant. What is relevant, is that the student is provided with an opportunity to prepare for the lesson. He will get more bang for his buck and will likely recommend you to all his flying friends.

Professional pilots, flying for the scheduled airlines, avoid strange field letdowns and for good reason. It is worth noting the majority of accidents that happen during IFR operations (especially single pilot IFR operations), occur during the approach phase at an airport the pilot has never flown into before. Seldom do these accidents happen during approaches at home. Why is this? Perhaps chart reference is kept to a minimum during the familiar approach because the pilot knows the pertinent information by heart. The less time spent looking at the approach chart, the more time the pilot can spend on the "six pack" controlling heading, altitude and airspeed. Conversely, the more time spent seeking data from the chart, the less time the pilot has to control his aircraft.

This concept is especially significant in preparing your student for his flight test. Any time spent practicing approaches not likely to be used during the check ride is time not used to the student's advantage. The more times the pilot flys the approaches likely to be used, the more likely he is to successfully execute those approaches for the examiner. Does this mean we are teaching the test? No! You are only trying to prepare the student to acceptably perform the instrument approaches he is likely to encounter on the practical test.

ADDING NOTES TO YOUR CHARTS
Media File: | Tracy Approach Chart |

Advance planning includes noting anything unusual about the trip including terminal areas. For example, the VOR approach into Tracy, California involves an unusually complex navigation radio setup if the aircraft is not DME equipped. Manteca VOR provides the course guidance but Modesto VOR makes up the two cross bearings required during the approach. The missed approach requires the use of the Sacramento VOR 157° radial. Since Modesto is required to identify the FAF (final approach fix) Sacramento can not be tuned in until after commencing the final descent. Once Sacramento is finally tuned in, the pilot will be unable to identify the Morse code because of the low altitude and the distance from Sacramento. This means the student must identify Sacramento and make sure it is usable before setting in Modesto and beginning the approach. In the unlikely event Sacramento is off the air, the pilot should discuss an alternative missed approach procedure with Stockton Approach Control before commencing the procedure.

Advance planning might also include adding a note to the approach chart showing the reciprocal of 157° (337°) since the procedure requires the pilot to fly the radial northwest bound to Tracy intersection. Although figuring reciprocals may be easy for you, the student will not likely find it a simple task, especially while flying the aircraft. Adding a note showing 019° for the outbound heading of the teardrop entry into the missed approach hold will also help reduce your student's work load. Teach your students to add whatever notes may be helpful to their approach charts. After all, that is how approach charts came into existence in the first place. Capt Jeppesen kept a book of notes for himself showing what he considered to be "need to know" information for each of the airports he flew into.

ATTITUDE PLUS POWER = PERFORMANCE

Up to now we have been discussing how to reduce the work load of single pilot IFR operations by planning ahead. Now lets look at another area that is not often covered adequately. When ever the instrument student has difficulty holding a heading within 10° or an altitude within 100 feet or an airspeed within 10 knots, the instructor most often concludes that the student is not scanning or "cross-checking" the instruments. The student usually accepts the instructor's criticism and hangs his head and laments the fact that he can not scan. But could it be that the student is in fact scanning, perhaps even the way the instructor taught him, but the problem is with the scan itself. Often too little attention is paid to this skill. We all know how important scanning or cross-checking is but we may not know the best method to teach this skill.

First of all, the pilot must have an objective in mind. He may be looking at the appropriate instrument at the appropriate time but if he does not know what to look for, then he will not know if he has accomplished what he needs to accomplish. The objectives in a simple fixed gear training aircraft can be distilled down to just five, sometimes called the five configurations. They are:

1. Climb;                                   
2. Cruise level;                                   
3. Cruise descent;                                   
4. Approach level; and                                   
5. Approach descent.

By setting established attitudes and power settings for each configuration, the pilot can obtain the desired performance in each situation without chasing needles. The following table provides a sample of attitudes and power settings and resulting performance for a typical training aircraft for each configuration.

Of course, the power setting required to accomplish a given performance on any given flight will be a function of density altitude and gross weight, but the numbers shown above represent a good starting point. Use the concept to work up a performance chart like the one above for the airplane you will be using for your lessons. Adjust the power settings and attitudes as necessary to achieve the performance values you wish to use.

Pick a nice smooth day and start with the cruise setting first. After leveling off from your initial climb, set the power setting you intend to use for cruise, maintain a constant altitude, trim the aircraft, adjust the attitude indicator to show the wings on the horizon (level), and note the indicated airspeed on your performance chart.

Next, determine an attitude and power setting that will maintain the indicated cruise airspeed but in a 500 fpm rate of descent (cruise descent). Since the aircraft is already trimed to maintain cruise airspeed, a gradual power reduction of 250 rpm will normally result in the attitude pitching down slightly to maintain the airspeed. Use elevator input as necessary to reduce pitch oscillations as lift, weight, thrust and drag seek equilibrium. For a constant speed propeller, use a gradual power reduction of 5" of manifold pressure. The rule of thumb is that a power change of 250 rpm or 5" of manifold pressure will change the verticle velocity by 500 fpm if the airspeed is kept constant. Once the cruise descent is stabilized, note and record the power setting and attitude (probably between 1 and 2 degrees pitch down and 250 rpm or 5" less than cruise level).

Approach level is the next configuration to work out. The adjustment here may be simply trading airspeed for vertical velocity. Try adjusting the pitch attitude to 1 degree nose high while keeping power constant (you will have to adjust the throttle slightly for the increased load on a fixed pitch propeller). The objective is to bring the vertical velocity to zero and end up with a usable approach speed. Once you determine the attitude and airspeed for this configuration add them to your chart.

Use the rule of thumb to come up with the following values for the approach descent:

In the event of a missed approach, the climb configuration would follow the approach descent. In a typical training aircraft you will probably be able to go to full power (check the approved AFM). The objective here is to use a climb speed equal to the approach speed so that retrimming is not necessary. However, you also want at least a 500 fpm rate of climb and may have to settle for a slightly slower airspeed. Start with a 5 degree pitch up attitude and adjust as necessary to achieve the objectives.

After you have established the five configurations, discuss them with your student during the preflight briefing. Then let your student practice the attitudes and power settings in flight with out the hood so he (or she) can nail down the concept.

For retractable aircraft, APPROACH LEVEL will have two configurations; one for gear up and one for gear down. APPROACH DESCENT will always be with gear down to avoid landing with the gear selector in the wrong position.

A more complicated version of this method was developed by the military for their flight training programs during World War II to accommodate the complexities of the fighters, bombers, freight haulers and troop transports in use at the time. They called it ATTITUDE PLUS POWER EQUALS PERFORMANCE or flying by the numbers.

This method teaches the instrument student to set an attitude and power setting. By concentrating on the attitude indicator and holding it constant, the student will find that the performance indicators (airspeed and vertical velocity) will settle down very close to the desired values. Any discrepancies can be eliminated with minute adjustments to the attitude and/or the power setting. With this technique, the student will be able to fly the aircraft, on instruments, within PTS standards and without "chasing needles". Try it. You will like it!

An IFR flight consists of three basic phases: departure, enroute, and approach. The departure takes the aircraft from the departure airport, out of the terminal areas, and into the enroute structure, consisting primarily of the airway system, through which we navigate to the approach corridor, shown in Figure One. This corridor leads us to the ultimate goal of every IFR flight — a normal, safe landing at our destination airport.

IFR flying begins with proper planning. We have to know how we are going to get to our destination, what conditions our aircraft is likely to encounter along the way, and what information and equipment we will need for our flight.

THE WEATHER BRIEFING

Although computer access is becoming more popular with every passing day, teach your students to augment their computer based data with a weather briefing by phone. Train your student to ask very specific questions. What information should be requested? Use Figure Two as a guide.

METARs

These reports are actual measurements of the weather as it has occurred at a specific station at a specific time. Check METARs for: the destination, the departure airport, to determine if it has weather good enough that a return could be accomplished should a malfunction occur on, or shortly after, takeoff; the alternate, if one is required, to determine if the weather is at, or above, alternate minimums; and enroute stations, because the weather there will influence the pilot’s judgment if an emergency should occur—partial panel, for example.

If the weather is really marginal, the METARs for the past two or three hours should be compared to determine the actual trend of the weather, and to compare this to the forecasts. Do not hurry through this information. Get all the key items, such as sky cover and ceiling, visibility, or RVR if listed, altimeter setting and surface winds. Should a communications failure occur, this may well be the last information upon which the selection of an approach is made.

Get the Terminal Aerodrome Forecasts for the same stations. TAFs are not available for all stations, and area forecasts (FAs)may have to be used.

The destination forecast should be compared to the actual trend in the METARs. The forecast for the departure airport is of interest because of the possibility of having to return. TAFs for enroute stations are needed for possible emergencies, and also for the possibility of their being used as an alternate.

FAs for the enroute portion of the flight should be requested for an overall picture of the weather and also to answer the one, big questions—which way to the closest VFR weather conditions. This is to determine the best escape route should a complete electrical failure occur.

RELIABILITY

The accuracy of a forecast is limited by what is known and what can be measured. These result in a reliability factor. The reliability factor of weather forecasts is inversely proportional to the length of time that has passed since the forecast was issued.

Good weather forecasts are likely to be correct for up to 12 hours. A forecast for bad weather is not likely to be correct for the same period of time. Ceiling and visibility forecasts are not reliable beyond two or three hours. In other words, a twelve-hour forecast of good weather has a reliability factor of about 80%, whereas a twelve-hour forecast of bad weather is only about 45% reliable.

In cases where distinct weather systems are involved, such as fronts and precipitation, there is a tendency to forecast too little bad weather. Errors in forecasting the time of a specific weather occurrence are more prevalent than errors in forecasting the occurrence itself.

Some high reliability forecasts that are usually about seventy-five percent correct are the passage of fast-moving cold fronts within plus or minus two hours; and the passage of slow- moving warm fronts within plus or minus five hours. Rapidly lowering ceilings in pre-warm front conditions are accurate to within plus or minus two hundred feet and within a time accuracy of plus or minus four hours. In areas where radar is available, the forecast of thunderstorms is accurate to within one or two hours.

Now, here are some very low reliability forecasts; the location of severe turbulence; the location and occurrence of heavy icing; the location and occurrence of tornadoes; ceilings of 100 feet or less; and thunderstorms before they are formed— all very low reliability forecasts.

The occurrence of both icing and turbulence is local in nature and transient in character. Since an aircraft is about the only instrument that can measure these phenomena, there is no other way to verify the forecasts. Hence, the importance of Pilot Reports, PIREPS.

Icing and turbulence forecasts are made for a relatively large volume of air space, compared to their localized extent. The occurrence of these hazards can be forecast with between fifty to seventy-five percent accuracy. But, the intensity and the exact location are unreliable. This means that when flying through a volume of air space for which these hazards have been forecast, the probability of an actual encounter is not fifty to seventy-five percent, but about five to fifteen percent. The regions of actual icing and turbulence are small compared to the overall volume specified in the forecast. Nevertheless, the possibility of the hazard exists, and good judgment must be used by the pilot.

ALTERNATES

Referring to the information in the forecasts, the pilot can determine if an alternate airport needs to be designated on the flight plan. The regulations state that if the first airport of intended landing has a standard instrument approach procedure and, for at least one hour before and one hour after the estimated time of arrival, the weather reports or forecasts or any combination of them indicate the ceiling will be at least two thousand feet above the airport elevation; and the visibility will be at least three statute miles, an alternate airport need not be designated.

According to the latest FAA interpretation, the words "chance of" or "occasional" in a forecast constitute a valid forecast and must be considered when determining the need for an alternate. Also note that if the first airport of intended landing does not have a standard instrument approach procedure, an alternate airport must be designated regardless of reported or forecast weather conditions.

The regulations then state that the weather forecast for the alternate airport must indicate, at the estimated time for arrival, that the ceiling and visibility will be at or above the alternate minimums published in the standard instrument approach procedure for that airport, or if no alternate minimums are published; in the case of a precision approach a ceiling of at least six hundred feet and visibility at least two statute miles; in the case of a non-precision approach, a ceiling of at least eight hundred feet and visibility at least two statute miles. If the airport designated as the alternate has no instrument approach, the weather forecast must indicate that descent from MEA and landing can be accomplished under Basic VFR.

Remember this is for flight planning, when enroute to the alternate the actual published minimums for the approach apply.

No pre-flight planning is complete without the Radar Summary and Pilot Reports. As previously mentioned, an aircraft is the only tool available to measure certain weather phenomena. PIREPS are the most reliable source of information on cloud tops, icing, thunderstorms, and turbulence. However, remember that thunderstorms move. The Radar Summary, used in conjunction with the other information, can give a three-dimensional view of what’s going on. And, finally, you need the winds aloft forecasts for the route.

It should be mentioned here that once airborne, the pilot can get up-to-date pilot reports, and also contribute to the information available to other pilots, on frequency 122.0, the Enroute Weather Advisory Service, Flight Watch Service. This is a party line where all pilots wishing real time weather can ask for current pilot reports, or just listen to other pilots giving weather on the frequency.

Also a check of the Flight Data Center (FDC) Notams for any changes that may have occurred on approach plates or charts is a required part of your pre-flight planning.

ROUTE LOGS
Media File: | Fig. 4 - Quadrant Method | Media File: | Fig. 3 - Route Log |

With a complete weather briefing, the pilot can make his go or no go decision. If the decision is go, a route log should be prepared in order to obtain enroute times and other information required for the flight plan. The type and complexity of the route log is technique and will vary with the pilot’s proficiency and the type of equipment. Figure Three shows an American Flyers Route Log. It contains all the information needed to plan a flight. Its use will reduce chart reference, a must for single pilot IFR. It will provide the information needed to make required reports, and it will furnish the data necessary should a communications failure occur.

We probably all know pilots who just make a few scratches on the enroute chart and that’s all. If, when they are called upon for an estimate, they can come up with the required information quickly, then, those scratches are an adequate flight log for that pilot. But most of us need more.

Here’s a tip for filling out the ground speed estimate on your Flight Log. Please refer now to Figure Four. On any given course, if the wind is on the nose of the aircraft, the full value of the wind is subtracted from the true airspeed. For example, if the true airspeed is one hundred knots and we have twenty knot headwind, the groundspeed will be eighty knots. Now, if we have a quartering headwind, one-half the value of the wind is subtracted. If it is a direct crosswind, one-fourth of the value of the wind is subtracted. For a quartering tail wind, one-half the value of the wind is added to the true airspeed. When using this method to calculate groundspeed during an approach, a direct crosswind can be disregarded because of the short distances involved.

THE FLIGHT PLAN
Media File: | Fig. 5 - FAA flight plan form |

The FAA Flight Plan, shown in Figure Five, or as it might be amended in the future, should be filed at least thirty minutes prior to the estimated time of departure. If the departure is delayed for longer than one hour, the pilot should notify ATC. Most of the boxes on the Flight Plan are self explanatory. The pilot should make sure he uses the proper suffix in Box three so that ATC has the information needed to utilize all facets of the navigation equipment and transponder capabilities that are available. These suffixes are listed in the AIM. Box Ten, the Estimated Time Enroute, should be the time the pilot estimates it will take to fly from the departure airport to the destination airport.

Fill out Box Twelve, the Fuel on Board, accurately. This could have a great deal to do with how long ATC would protect airspace for the pilot should a communications failure take place.

All flight plans are filed through a Flight Service Station, and to minimize delays, the IFR clearance should be obtained prior to departure. An IFR to VFR on top, a pop-up, or a tower enroute clearance can be obtained directly from ATC facility without going through the normal filing procedure.

A flight plan requesting clearance to VFR conditions on top should be filed following normal procedures. In Block nine of the flight plan form, indicate the destination as "VFR-on-Top." This would be appropriate when there is a low overcast at the departure airport with the tops of the clouds at, say, three thousand feet and clear above, the destination is clear. A clearance in this case might read, "Cleared to VFR conditions on top via Direct Joliet VOR; if not on top by five thousand, maintain five thousand and advise." When in the clear on top, the pilot cancels IFR and proceeds to his destination VFR. Never accept this kind of clearance without the phrase "if not on top by ... maintain ... and advise!"

Be certain that the pilot report, or other information used to determine the height of cloud tops, is accurate. If, in our example, the flight was not on top at five thousand, a holding clearance to absorb a thirty minute delay while additional flight plan information was processed would not be uncommon.

The Pop-up, or obtaining an IFR clearance from an ATC facility without having previously filed, is useful if you suspect that a VFR destination airport’s weather may turn to IFR. The best procedure to follow is to file an IFR flight plan prior to departure, or if already enroute, file with flight service by radio at least thirty minutes prior to the time you will need an IFR clearance. In this case the departure point will be the fix over which you plan to pick up your IFR. At certain high density facilities during peak traffic times, controllers may be unable to accommodate "pick-up" requests, so it is best to check this with flight service prior to departure.

At some locations, tower enroute clearances can be obtained without a flight plan simply by requesting clearance directly from ground control at the departure airport. Tower enroute describes a flight that proceeds from one approach control facility to another without entering airspace which is the responsibility of an enroute center. Listings of these routes, along with the maximum altitudes, are available in the airport/facility directory or Jeppesen supplement. ATC, due to work load or locally established procedures, may be unable to honor tower enroute requests without a flight plan, so, again, the best procedure is to file with flight service at least thirty minutes before departure.

To complete our Flight Plan, we need to know a couple of things about our aircraft’s performance.

Range - how much usable fuel is available and what is the consumption per hour. Remember to enter the total amount of usable fuel, in terms of time, actually on board the airplane. For IFR flights the minimum amount of fuel that must be aboard is enough to fly to the first airport of intended landing, then to the listed alternate airport, and then for 45 minutes at normal cruising speed. If your flight will not require an alternate airport, you must have enough fuel to fly to the destination airport and then for 45 minutes at normal cruising speed.

True airspeed - what will it be at the altitude selected. Of course, the wise pilot will know the emergency procedures thoroughly and will check weight and balance before every flight. The effects of improper loading can be disastrous, particularly when you’re IFR. We’ll also want to be sure the avionics aboard are adequate for the flight being planned.

There are several other things we need to check to determine if our aircraft is legal for the flight. Does it have the necessary documents aboard? Figure Six shows an easy-to- remember checklist—the word "ARROWE." The following documents must be aboard: The Airworthiness certificate, the Federal Registration certificate, the Radio license, the Operating limitations, a current Weight and balance, and the Equipment list — the ARROWE.

In addition, if used under IFR, the aircraft must have certain inspections completed. It should have a maintenance inspection appropriate to the type of operation. And, a VOR accuracy check within the preceding thirty days. A static system and altimeter check, within the preceding 24 calendar months.

Also, for IFR or VFR, the emergency locator transmitter battery must be within certain time parameters.

DOCUMENTS

ARROWE

Airworthiness certificate

Registration certificate

Radio station license (International flights only)

Operating limitations

Weight and balance data

Equipment list

        Figure 6

Other required checks include:

VOR accuracy check within the last 30 days

Static system and altimeter tests within the last 24 months

Transponder test within the last 24 months

THE PILOT

When it has been determined that the aircraft is legal, a check on the pilot-in-command is in order. The FARs do not require the logging of all flight time, but the pilot, in order to be legal, must meet certain currency requirements. These requirements are cumulative and are the minimum times that must be recorded.

For day currency, in order to act as the pilot-in-command carrying passengers, the pilot must have made three takeoffs and landings within the preceding ninety days. Note that if this requirement is not met, the pilot can solo the airplane to get the three takeoffs and landings, log them, and then legally carry passengers. Also, this requirement must be met in category and class of aircraft being used. Having met this requirement, for example, in a twin engine airplane, doesn’t meet the requirements if a single engine airplane is being used. If the airplane is a tail dragger, the landings must be to a full stop.

For Night Currency, again, in order to act as a pilot-in- command carrying passengers, three takeoffs and landings to a full stop within the preceding ninety days, at night, are required. These also must be in category and class of aircraft being used. If the pilot meets the night requirements, he also meets the day requirement.

When it comes to Instrument Currency, the regulations state that in order to act as pilot-in-command (whether carrying passengers or not) of an aircraft operating under instrument flight rules, the pilot must have performed and logged under actual or simulated instrument conditions, either in flight in the appropriate category of aircraft for the instrument privileges sought or in an approved flight simulator or flight training device that is representative of the aircraft category for the instrument privileges sought - 1) at least six instrument approaches; 2) holding procedures; and 3) intercepting and tracking courses through the use of navigation systems. If this experience is accomplished in an approved flight simulator or flight training device, the experience must be certified by an authorized instructor. The experience may also be attained under the hood with an appropriately rated safety pilot. The date, airport, and type of approach must be recorded, and if done with a safety pilot while under the hood, the name of the safety pilot should be recorded.

If a pilot should find that his currency has lapsed, he can make himself current again by acquiring the needed time and approaches in any of the approved methods. However, should he go for period of six consecutive months without being current, he cannot use his instrument rating without first taking an Instrument Proficiency Check. This check can be conducted by any valid instrument flight instructor, and must include tasks so indicated in the appropriate PTS. Completing a proficiency check makes the pilot current on instruments for six months. The Instrument Proficiency Check should not be looked upon as that which must be avoided at all costs. In fact, it is a short, economical way for a pilot to assure his currency for six months. In most cases a proficiency check takes less time and less work than does the acquisition of six approaches.

In order to act as pilot-in-command on any flight within the preceding 24 months, the pilot must have completed a Flight Review or the equivalent.

Now that the pre-flight planning is complete, and the airplane and the pilot are legal, there is still a very important item to be checked. Every pilot knows the importance of having up-to-date approach charts. But he cannot be sure that he does unless he checks the FDC notams. FDC stands for Flight Data Center, and these notams deal with procedure changes on instrument approaches, changes such as raising or lowering an MDA, or an altitude for a segment of an approach, appear in these notams until the approach chart can be revised. They are included with a subscription to the approach charts.

                     REGULATIONS PERTAINING

                          TO FLIGHT PLANNING

                             61.57     Pilot Experience

                             91.3       PIC Responsibility

                             91.103   Preflight Action

                             91.167   Fuel Requirements

                             91.171   VOR Checks

                             91.203   AC Documents

                             91.411   Altimeter Check

                             91.207   ELTs

                             91.413   Transponder Checks

All of the required documents may be aboard the aircraft and all of the maintenance inspections may have been completed and logged but the aircraft may still not be safe for instrument flight. Instruments must be checked for accuracy and normal operation. The altimeter must be set to the current altimeter setting and the indicated altitude checked for accuracy. The indication should be within 75 feet of the actual elevation in order to be considered safe for use in IFR operations. Check the airspeed indicator for normal readings while parked and while taxiing. Check the turn needle and ball during taxi turns for normal readings and the heading indicator to make sure it is reading properly. The attitude indicator should settle down within a few minutes after engine start. Up to 5 degrees of bank indication due to precession during taxi turns is considered normal.

CLEARANCES

All clearances come in four parts: The Clearance Limit, the En route Routing, the Altitude, and Remarks. This can perhaps be better remembered, and thus better analyzed, with the acronym CLEAR. CL for clearance limit, E for en route routing, A for altitude and R for remarks. Some ATC facilities will issue you an abbreviated IFR departure clearance. These may contain a departure procedure (DP), whether or not one was requested on the flight plan. A DP will be issued any time an ATC deems it appropriate. Preferred IFR routes beginning with a fix indicate that departing aircraft will normally be routed to the fix via a DP or RADAR vectors

If a STAR has been filed in the flight plan, it is considered part of the flight plan route, and isn’t normally stated in the departure clearance. "Cleared as Filed" doesn’t necessarily include the altitude requested in the flight plan. An en route altitude should be stated in the clearance. Example: Cessna 201 cleared to Peoria, as filed. Canal 2 departure, expect four thousand.

Sometimes the flight will be cleared to a clearance limit short of the destination. In most cases this is due to airspace jurisdiction. At the time of issuance there is no intention of holding the flight at that point. Instead, it is the responsibility of the controller to issue further clearance prior to the time the flight reaches the fix. However, if due to frequency congestion, further clearance hasn’t been received, the pilot is expected to slow to holding pattern airspeed, and upon reaching the clearance limit, enter the published holding pattern. If no holding pattern is depicted, the hold should be accomplished on the route on which the fix was reached. This is not to be confused with the action taken by the pilot if this should occur with a two-way radio communication failure.

DEPARTURE PROCEDURES

A Departure Procedure (DP) is a coded ATC departure procedure and may be issued by ATC without prior pilot request. The use of DPs simplifies clearance delivery. In order to accept a DP , you must have either the textual or graphic description. NOS now publishes DP's and STARS in the approach chart books.

Each DP contains a detailed departure procedure. The DP describes the route to fly from take-off to the departure fix. There may be one or more transitions from the departure fix to en route fixes. To specify a DP in your flight plan, list the DP identifier for the appropriate departure and transition. If you don’t have the DP charts, specify "NO DPs" in the remarks section of your flight plan.

The main purpose of a DP is to simplify clearance delivery. As mentioned before, a DP will be issued to a pilot any time ATC deems it appropriate. If the pilot has used the Remark section of the flight plan to indicate no DPs or STARs, the only effect it will have is to tell the controller that the DP will have to be issued in narrative form. A DP shows a visual and narrative description of both parts of the procedure: the departure and the transition. Once a pilot has been cleared to use a departure procedure, the printed procedure is mandatory until ATC clears the pilot to deviate.

Some DPs have minimum crossing altitudes, and minimum en route altitudes for various legs. Before accepting a DP, the pilot should make sure his aircraft has the capability to comply with these altitudes. A minimum climb of 152 feet per mile is required after crossing the fix, until reaching the MEA, or the assigned altitude.

The DP charts are very simple and should be used in conjunction with the area and en route charts. The symbols used are the very similar. Notice that the departure frequencies are conveniently posted, as is the narrative description of the procedure. The plan view not only depicts the departure routing, but also the key airways, and fixes that facilitate the transition into the en route structure.

A Standard Terminal Arrival (STAR) is a coded ATC arrival procedure established to simplify clearance delivery procedures. Use of a STAR requires that you have either the textual or graphic depiction available.

Each STAR consists of one or more transitions from enroute fixes to an arrival fix. The arrival route leads from the arrival fix to an initial approach fix or to a point from which you may receive radar vectors to an approach course. To file a STAR in your flight plan, list the identifier for the appropriate transition and arrival.

ATC may issue a STAR anytime they deem it appropriate, unless the pilot requests "No STARs." The pilot should indicate "No STARs" in the remarks section of the IFR flight plan if he (or she) does not have STAR charts available in the cockpit.

DEPARTURE
Media File: | Maric 3 Departure Procedure | Media File: | Fig. 10 - LOC RWY 22 Approach Plate |

It should be pointed out that when making an IFR departure, it is very important that the pilot have the approach charts for the airport of departure readily available, not just for the airport diagram, communication frequencies, and so on. But for another very important reason, Non-Standard Departure Procedures.

Whenever the surrounding terrain or the availability of airport facilities dictate takeoff minimums or departure procedures other than standard, the NOS Government Charts show the symbol "T" contained within a solid blue triangle. These procedures are described in a supplementary listing that accompanies the chart subscription.

A pilot has to determine, before departure whether obstacles can be avoided visually or if the published procedure should be followed.

Referring to Figure Ten, it can be seen that Bar Harbor, Maine, is a typical example. When departing on the specified runways, the pilot must climb to 1200 feet on a heading of 218. Then make a climbing right turn, back to the NDB, and enter a holding pattern. He must then climb in the holding pattern to the MEA, or the assigned altitude, before proceeding on course.

Apparently the airport is surrounded by obstructions or high terrain. This is a very necessary piece of information for any departure—VFR or IFR. So, to repeat, if the symbol "T" appears on the NOS approach chart, check the supplementary listing.

At airports where departure procedures are standard, there is a good rule of thumb to follow with regard to how high to climb after takeoff before making any turns. The circle to land MDA for any runway will provide at least 300 feet of obstacle clearance for a distance of 1.3 miles from the end of the specified runway. If the pilot climbs to this altitude before proceeding on course, he should have adequate obstacle clearance within 1.3 miles of the runway.  However, the pilot is always responsible to verify there are no obstructions along his expected flight path before becoming established on a published airway.

When departing an airport where there is no published approach and hence no departure procedures, the pilot must determine for himself what action will be necessary to ensure safe departure. It should be pointed out here that the FAA has prescribed Standard IFR Take-off Minimums for commercial carriers. These are: One statue mile of visibility for aircraft having two engines or less, and one-half statute mile for aircraft having more than two engines. These minima do not apply to a non-commercial flight operating under Part 91. However, safe practice would dictate their use.

When departing an airport without an operating control tower, ATC may assign a clearance which contains a provision for the clearance to be void if not airborne by a specific time. A pilot who does not depart prior to the clearance void time must advise ATC as soon as possible of their intentions. ATC will normally advise the pilot of the time allotted to notify ATC that the aircraft did not depart prior to the clearance void time. This time cannot exceed 30 minutes. Failure of an aircraft to contact ATC within 30 minutes after the clearance void time will result in the aircraft being considered overdue and search and rescue procedures initiated.

ATC provides radar traffic advisories on a workload permitting basis. Couple that with the fact the radar does not "see" every traffic conflict, and it then becomes that collision avoidance is always the responsibility of the pilot. This is true regardless of the type of airspace being flown, the type of operation being conducted, whether IFR or VFR, and regardless of radar coverage. The only time the pilot is relieved of this responsibility is when he or she is actually in the clouds. Even then the pilot must maintain situational awareness and be alert to possible conflicts. The bottom line is that it remains the pilot's  responsibility, regardless of whether operating under IFR or VFR, to see and avoid traffic when flying in VFR conditions.

Be that as it may, radar traffic advisories do reduce the risk of mid air collisions and should therefore be utilized and understood. Controllers issue traffic information by providing the azimuth from the nose of your airplane in terms of the twelve hour clock. Each hour position represents 30 degrees. The controller also provides the distance in nautical miles, direction of movement and, if known, the type and altitude of the other aircraft.

Example: "TRAFFIC 2 O’CLOCK, 3 MILES, NORTHBOUND, A DC-3 AT 6 THOUSAND".

Look for this traffic 60 degrees to the right of your projected ground track.

Radar detects ground track, not heading. A crosswind correction may place the traffic in a different position relative to the nose of your airplane than indicated by the controller.

Controllers issue safety advisories when, in the controllers judgment, the aircraft is dangerously close to terrain, obstacles, or other traffic. This procedure is for use in time critical situations where the safety of an aircraft is in question. It is up to the pilot to determine what course of action, if any, is required in response to a safety advisory.

POSITION REPORTS

When radar is not available, ATC depends on position reports from pilots to ensure separation between aircraft. At each compulsory reporting point, or at any point requested by ATC, provide the controller with the following:

1. Identification.

2. Position.

3. Time.

4. Altitude (State actual altitude when VFR-ON-TOP).

5. ETA and name of next reporting point.

6. The name only of the succeeding reporting point.

7. Pertinent remarks.

If ATC advises "RADAR CONTACT", do NOT make any further position reports. Resume normal position reporting if the controller states "RADAR CONTACT LOST" or "RADAR SERVICE TERMINATED".

Make the following reports at all times:

1. Vacating an assigned altitude for a newly assigned altitude.

2. Any altitude change when operating on a VFR-ON-TOP clearance.

3. Unable to climb or descend at least 500 feet per minute.

4. A missed approach.

5. Change in true airspeed of 5 percent or 10 knots, whichever is greater, from that filed in the flight plan.

6. Time and altitude reaching a holding fix or clearance limit.

7. Leaving an assigned holding fix.

8. Any loss of navigation or communication capability.

9. Any hazardous weather encountered during flight.

10. Any information relating to the safety of flight.

When ATC does NOT have you in radar contact make these additional reports:

1. Leaving the final approach fix inbound on an instrument approach.

2. A corrected ETA if it becomes apparent a previous ETA is in error by more than 3 minutes.

HOLDS
Media File: | Fig. 12 - Hold | Media File: | Fig. 13 - Hold with Crosswind | Media File: | Figure 11 |

In today’s system, holding patterns while enroute are rare, indeed. Most spacing is accomplished through the use of speed reductions and vectors. But occasionally holds do occur, particularly in a terminal area. And so the pilot must be able to comply.

What is a holding pattern? Well, basically, it’s a parking lot, used for separation enroute or for approach sequencing. What are its dimensions? They are no longer described in physical terms. Protected airspace is based on all pilots conforming to certain criteria. The maximum allowable indicated airspeed is 200 knots for all aircraft 6000 feet and below.  Some holds may indicate a restriction of 175 knots.  

The outbound leg is adjusted so that the inbound leg is one minute long, at or below fourteen thousand feet MSL. All turns are made at standard rate, or thirty degrees of bank, whichever is less, or twenty-five degrees of bank, if a flight director is used. If these criteria are adhered to, the protected airspace will not be exceeded.

Referring to Figure Eleven, you can see that there are four basic parts to a holding clearance: The fix, at which to hold; the course, on which to hold; a direction that identifies the course; and a time to expect further clearance. If the turns are non-standard to the left, it is so specified. If nothing is said, it is to be understood that all turns are to the right. This is not to say that left turns can’t be made during the entry, just that once established in the hold, all turns are to the right. Sometimes the altitude is verified.

After receiving the clearance, the next step is to visualize the pattern. This is accomplished by picking out the holding course from the clearance, visualizing the aircraft going inbound to the fix on the course, and when reaching the fix, making the appropriate turn.

The secret of success is to pick out the proper course, and realizing that whenever the aircraft is established on the holding course, it must be going inbound to the fix. The most common error in visualizing the hold is to confuse the purpose of the direction given in the clearance. The direction does not refer to the assigned holding airspace. It only identifies the holding course.

Next comes the entry. The recommended entries based on the seventy degree line are just that—recommended. In the real world, the pilot can enter the hold any way he likes. It is conceded that if the most logical entry is made, it will be the one recommended. But the point is, the pilot shouldn’t get worked into a sweat about whether or not he is making the correct entry. The objective is to get into the hold without becoming disoriented or exceeding protected airspace.

At fixes where holding is frequently accomplished, the charts show published holds. These are not only to reduce communications, but are also compulsory whenever holding is necessary, and, no other instructions have been received. An example of this would be reaching a clearance limit, and due to frequency congestion, not having received further clearance. In this situation the published hold is negotiated.

Figure Twelve shows a typical holding pattern. The holding fix can be a VOR, VORTAC, NDB, a locator outer marker, intersection, waypoint, DME fix, or any other point in space that can be identified with navigational equipment. At the fix end, opposite the fix, is the abeam point. Whenever the abeam can be identified, it is the place where timing for the outbound leg is started. The abeam point can be identified when the holding fix is a VOR, VORTAC, or NDB.

If the fix is a VOR or VORTAC, this point is recognized by the "off" indication on the To/From indicator, if the OBS is set to the inbound course. If it were an NDB, the ADF receiver is used to identify the abeam point. When the abeam point cannot be identified, the outbound timing is started when the wings are level on the outbound heading. This situation would exist if the fix were a marker beacon, or an intersection that was identified by radials that were not ninety degrees to each other.

When the fix is an intersection that is located a substantial distance from the facilities used to provide the radials, the pilot should be aware of the small amount of needle sensitivity. A little deflection could represent a lot of distance. Proper interception and bracketing procedures must be used.

Another thing about intersection holds is that the preferred station should be used. The charts indicate the preferred facilities with arrows. If, when in an intersection hold, one VOR receiver becomes inoperative, the pilot shouldn’t hesitate to request two-minute legs. This provides more time to switch the receiver back and forth. If it is a DME hold, the outbound leg isn’t timed. The hold is based on DME distance only.

The outbound leg in a no-wind condition would be one minute long. Once established in the hold, this leg is strictly dead reckoning. The pilot flies a heading for a certain length of time and that’s it. The inbound leg is accomplished on the assigned holding course, when the fix is a VOR, since theoretically the aircraft is never more than one minute from the station, the needle is very sensitive and moves quickly. If the aircraft is equipped with a flight director, placing it in the approach mode will ease this problem. In any event, proper bracketing procedures are a must, so that each consecutive pattern starts from exactly the same place.

If there is a headwind in the holding pattern, the outbound leg would be less than one minute long. If there is a tail wind in the hold, the outbound leg would be greater than one minute. Notice the difference in the shape of the ground tracks.

Figure Thirteen shows the shape of a holding pattern if a cross wind is present. Note that it is egg shaped rather than like a race track. This is because all turns are made at standard rate and so the upwind and downwind turns have different radii.

Cross wind corrections are made by adjusting the heading on the outbound leg, not by changing the rate of turn. Here again, it can be seen that it is most important that when coming out of the turn at the outbound end, the aircraft get established on the holding course, track it inbound, and cross directly over the fix. Each subsequent pattern and correction must be started from exactly the same spot, or the corrections are meaningless.

At some point during every IFR flight, the aircraft must leave the enroute phase and enter the approach phase. The list below shows the basic methods that ATC uses to accomplish this connection. The technical name for these connections is Terminal Routings. Our use of the word "transition" is intentional, because it semantically suggests what is actually taking place. The aircraft is transitioning from the enroute structure into the approach structure.

• AIRWAY TRANSITION
• PUBLISHED TRANSITION
• NO PT TRANSITION
• DME ARC
• RADAR VECTORS
• AUTHORIZED HOLD

A specific example of each method will be covered in detail. However, in order to understand this discussion of procedures, the pilot must have a thorough knowledge of certain terms.

First of all, to what is the connection being made. Figure Fifteen schematically shows the approach corridor, with its primary and secondary obstacle clearance areas for each segment of the approach. It shows the relative width of protected air space for each segment. It shows the circle-to-land obstacle clearance area, and the missed approach re-entry path.

The initial segment of the approach, and therefore, the approach itself, starts at the initial approach fix, or IAF. The altitude at which the aircraft crosses the IAF is defined as the initial approach altitude. This should not be confused with the altitude prescribed for the initial segment, which is called the Initial Segment Altitude. The former is usually higher than the latter, and a misunderstanding on the part of the pilot could have disastrous results.

The aircraft starts inbound in the corridor normally at the beginning of the intermediate segment. This part of the corridor usually extends for a distance of ten nautical miles from the approach facility, the exact distance is noted on the profile view of the approach charts. It is very important for the pilot to realize that the altitude prescribed for the intermediate segment is safe only when operating on the segment, within the length confines of the corridor.

The approach gate is located one mile outside the final approach fix, or five miles from the runway, whichever is the greater distance. This point is important to the pilot, because most approach procedures are designed to get the airplane inbound, in the corridor, at least one mile outside this gate. Even on radar vectors, the controller can not turn the airplane inside this point without the pilot’s permission.

The phrase, "Cleared for the approach," is authorization by ATC for the pilot to take over and negotiate the designated instrument approach procedure. He must not do this before receiving this clearance.

A cruise clearance authorizes the pilot to climb to and descend from the altitude specified in the clearance. It is also an approval for the pilot to proceed to and make an approach at the destination airport. It is not authorization to descend below the appropriate IFR altitude at any time.

Now the difference between the terms "straight-in approach" and "straight-in-landing" must be understood. There are seven ways to enter the approach corridor: course reversal (procedure turn, tear drop, or holding pattern), visual approach, contact approach, NOPT transition, radar vectors, DME arc, and from a hold at the final approach fix. All but the course reversal method are considered straight-in approaches. When cleared for a straight-in approach, a course reversal may not be made unless the pilot requests it and ATC approves the request.

A straight-in- landing, on the other hand, is when the approach procedure specifies a runway and the pilot is in a position to transition and land on that runway from the approach. No circle-to-land maneuver is needed. Normally a straight-in landing will have lower minimums than a circle-to-land maneuver.

SEGMENTS OF THE APPROACH

There are four segments to a typical instrument approach procedure: 1) initial; 2) intermediate; 3) final; and 4) missed approach.

The initial segment of an approach is that segment that positions the aircraft inbound in the approach corridor, within the prescribed limitations, and onto the intermediate segment, if the procedure has one. Initial segments can consist of a DME arc, radial, bearing, heading, radar vectors, or combination thereof. Procedure turns are initial segments. The initial segment altitude will provide at least one thousand feet of obstacle clearance, if it is conducted within the prescribed limits. If the initial segment is a course reversal, it must be conducted within the prescribed distance on the designated side of the approach course. Initial segments are shown on the plan view of approach charts.

The intermediate segment blends the initial segment with the final segment. It is the segment in which aircraft configuration, speed, and position adjustments are made for entry into the final segment. It is usually the segment on which the aircraft starts inbound in the approach corridor. It must be within thirty degrees alignment with the final, and is usually ten miles long. The intermediate segment altitude will provide at least five hundred feet of obstacle clearance within the intermediate limits of the corridor. Not all approaches have intermediate segments.

The final segment is where alignment and descent for landing are accomplished. In the case of an ILS approach, this descent is made on the glide path, to an altitude called a decision height, or DH. If, when at the DH on the glide path, the proper landing criteria are not met, a missed approach must be executed. On an ILS, the final segment begins at the point where the glide path is intercepted and ends at the DH. On a fully operating ILS, the DH is usually two hundred feet above the touch down zone. On a non-precision approach, the final segment begins at the final approach fix, or at the end of the initial segment if the facility is on the airport. It ends at the Missed Approach Point (MAP) which is normally the runway threshold, or the airport boundary. Occasionally, in mountainous terrain the MAP may occur at a point short of the airport with the remaining distance flown visually. This is done to provide a safe escape route away from mountainous terrain if visual conditions do not exist at the MAP. The lowest altitude authorized on the final segment of a non-precision instrument approach is called the Minimum Descent Altitude (MDA). The MDA will provide at least two hundred and fifty feet of obstacle clearance within the final limits of the corridor for a straight in landing, and at least three hundred feet of clearance within the corridor and obstacle clearance area for a circle-to-land maneuver.

In mountainous terrain, because of the induced altimeter errors and pilot control difficulties, with winds of twenty knots or more, obstacle clearance is raised by as much as five hundred feet.

The missed approach is where the aircraft re-enters the initial segment or the enroute structure. The missed approach segment begins at the missed approach point, and re-enters the initial segment or enroute structure, providing obstacle clearance on a climb gradient of two hundred feet per nautical mile. The missed approach point on an ILS is at the DH. On a non-precision approach, the MAP may be at the beginning of the runway, or field boundary, or short of the airport as described above.

MINIMUMS

The lowest altitude you may use on an approach depends upon the type of approach, the airplane approach category, and the landing runway. A speed of 1.3 x Vso determines the airplane’s approach category (Vso is the stall speed in landing configuration at maximum gross landing weight).

You may use the STRAIGHT-IN minimums when landing on the runway specified in the procedure (i.e. S-ILS 27). This altitude is the Decision Height (DH) for a precision approach or the Minimum Descent Altitude (MDA) for a non-precision approach (glide slope inoperative).

Landing on ANY other runway requires the use of the CIRCLING MDA. Some approaches show a SIDE-STEP MDA which applies to a parallel runway. In the absence of side-step minimums, use the circling MDA when landing on a parallel runway.

The visibility minimum for landing is in statute miles or hundreds of feet Runway Visual Range (RVR). A dash separates visibility in statute miles from the DH or MDA. A slash separates RVR values from the DH or MDA.

When operating under FAR Part 91, you may always fly an approach to minimums, regardless of reported or actual weather conditions. You may NOT land unless YOU determine the flight visibility is at or above the minimum shown. Visibility is the ONLY legal weather criteria for landing.

Immediately following the visibility value is the AGL altitude of the DH or MDA. For straight-in minimums this value is the height above the landing threshold, Height Above Touchdown (HAT). For circling MDA’s this is the Height Above the Airport elevation (HAA).

LANDING CRITERIA

Flight visibility at or above the minimum prescribed by the approach procedure is the only criteria as to whether or not a pilot can legally land at an airport. There are different kinds of visibilities. Prevailing visibility is the horizontal distance that the official observer can see objects of known distance over at least one half of the horizon. Runway visibility value, or RVV, is usually determined by an instrument, and represents the distance along the runway that the pilot can see unlighted objects or unfocused objects of moderate intensity. It is stated in terms of miles and fractions thereof.

Runway visual range, or RVR, is an instrumentally derived value that represents the horizontal distance that the high intensity runway lights can be seen down the runway from the approach end. It, too, is measured by an instrument and is updated only once a minute. The brighter the lights, the higher the RVR. This is its main advantage. RVR components are a projector and detector, set up either two hundred or five hundred feet apart along the portion of the runway where the landing is normally made.

This can be a disadvantage because the readout in the tower is based on this measurement, and doesn’t necessarily reflect the visibility on the remaining part of the runway.

This is why, in order to use RVR, the runway must have instrument runway markings, or all-weather runway markings that are visible, and the high intensity runway lights must turn amber on the last two thousand feet of runway. If the pilot should touch down safely, and then, during the roll out, encounter a dense obscuration, the runway markings and lights would be the only guidance information available to him. If the markings aren’t visible, such as being covered with snow, a necessary adjustment in visibility minima will be made.

Some major airports have roll out RVR reports. Whenever an airport reporting both RVR and prevailing visibility, the RVR takes precedence for a straight in landing on the RVR runway. If the aircraft is going to land on any other runway, the prevailing visibility applies. If the approach chart states visibility as RVR, but RVR is not being reported for the operating runway, it must be converted to terms of statute miles by use of a published table.

Now, let’s talk about landing criteria. Again the only meteorological criteria as to whether or not an aircraft can legally land out of a published instrument approach, is that the visibility must be at or above the landing minimum prescribed for the procedure. Regardless of reported values of RVR or prevailing visibility, the FARs state that the pilot must determine that the flight visibility is at or above the prescribed minimum. In addition, before continuing an approach beyond the missed approach point, the pilot must have the approach lights, runway lights, runway markings or the runway itself in sight. And before descending below the MDA or DH, the pilot must determine that the aircraft is in a position to make a normal descent to the runway.

If, when at or beyond the missed approach point, you do not have the required minimum flight visibility, or you do not have the runway environment in sight, execute the missed approach. ATC will no longer ask a pilot who is inbound for an approach to an airport that is reporting below published minima, what his intentions are. They no longer advise the pilot that the airport is below published minimums, because the minimums vary so much with different operations, pilots, and equipment. It is still true, however, that ATC is required to report to an FAA district office as an incident, any landing that is made when the visibility is being reported as less than one- half mile, or the RVR is less than the published minimums. And the pilot may be asked to explain to the FAA the circumstances of the landing.

In the real world, any time a pilot lands at an airport that is below minimums, and any kind of an accident or incident should occur, the FAA would probably construe it to be careless and reckless operation. At best, it can hardly be called good operating practice.

Now, let’s explore the difference in concept between a precision and non-precision approach. Figure Sixteen shows that there is a very basic difference in concept between a precision and a non-precision approach. And, therefore, a difference in the techniques used to negotiate each one. The most obvious differences are the obstacle clearance provided by the final segment, and the location and means of identifying the missed approach point. In regard to the location of, and the identification of the missed approach point, no person may operate an aircraft below the MDA, or continue the approach below the DH, unless the runway threshold or approved lighting aids or other markings identifiable with the runway, are clearly visible to the pilot and the aircraft is in a position from which a normal descent-to-landing can be made.

Notice how, with a precision approach, the regulation states that the pilot will not continue the approach below the DH. This means that the missed approach is located where the decision height altitude coincides with the glide path. At this point, a decision as to whether or not the criteria have been met must be made by the pilot. If not met, a missed approach is executed. This missed approach point usually occurs at, or near, the middle marker.

The implication is also made, and is true, that adequate obstacle clearance on the final segment, from the final approach fix to the missed approach point, is guaranteed only if the aircraft is on or above the glide path. Thus, to be safe, the pilot must maintain the glide path angle, or at least never go below it. A non-precision approach is as good and safe a let down to its non-precision minimums, as the ILS it to its precision minimums.

The only legal weather criteria for landing, as we said, is visibility. That does not in any way mean that the pilot can descend as low as he wants on the final segment. The lowest safe altitude that the pilot can descend to is the minimum descent altitude, MDA. Most of the accidents that happen on non- precision approaches, happen because the pilot went below the published MDA. The published MDA provides at least two hundred and fifty feet of obstacle clearance, in the case of straight in landing, anywhere in the final portion of the approach corridor. And, at least three hundred feet in the case of circle-to-land maneuver, within the obstacle clearance area.

Two criteria must be met before a descent below the MDA is authorized. The pilot must have the runway environment in sight, and the aircraft must be in a position from which a normal descent to landing can be accomplished. If both these criteria are not met by the time the missed approach point is reached, a missed approach must be executed. This position from which the runway can be seen and normal descent can be accomplished will be referred to as the Visual Contact and Descent Slot.

When the final segment is not aligned with a runway, only circling minimums apply. The procedure name does not indicate a runway number. This does not prevent you from landing straight-in if you have the runway in sight in enough time to line up with it.

As in Figure Seventeen, a Visual Descent Point (VDP), indicated by the symbol "v", shows the earliest position to begin descent to the runway. The VDP establishes a descent angle of about 3 degrees.

RNAV approaches indicate a descent angle for use if your RNAV equipment has vertical guidance capability. Setting the angle shown in the profile view will permit the airplane to arrive at the MDA at the distance shown from the runway threshold.

THE MISSED APPROACH SEGMENT

The missed approach segment begins at the Missed Approach Point (MAP) and ends at the missed approach fix. In the event it becomes necessary to abandon the approach before reaching the MAP, obstacle clearance will only be assured by proceeding to the MAP at or above the MDA or DH before executing a turning maneuver.

A holding pattern depicted at the missed approach fix indicates how to "park" your airplane while you decide what to do next. You may try the approach again, try a different approach to the airport, hold and wait for the weather to improve, or proceed to an alternate airport. Keep in mind, when considering your options, that you must divert to the alternate while you still have enough fuel to get you there.

Ask yourself the following questions to determine where the missed approach segment begins.

Is the approach a precision approach?

• If the answer is yes, the MAP is the decision height. If the answer is no, go to the next question.
• Is DME required to fly the procedure?
• If it is, the MAP will be a DME fix shown in the profile view. If DME is not required, the distance to the MAP will appear below the airport sketch.
• If no distance to the MAP appears below the airport sketch refer to the profile view. The MAP occurs upon crossing the navaid or waypoint used to identify the MAP. In this case, station passage indicates the MAP.

ADVANCE INFORMATION FOR THE INSTRUMENT APPROACH

The ATIS or controller will advise you of the approach in use at your destination. This is provided for planning purposes only. Changing weather and traffic conditions will affect the handling of your flight. If you are not able to fly the approach in use or want a different approach, advise ATC immediately.

Where ATIS is in use, the approach controller will expect you to already have the appropriate information prior to your initial call. As discussed earlier, this is not always possible. If you are able to pick up the information ahead of time, let the controller know you have "information alpha" (or bravo, or whatever letter identifies the ATIS data) on your initial call. If you do not have the information when instructed to contact approach, simply state "negative ATIS" on your initial call. Do not delay calling approach when instructed to do so since the controller is waiting for your call.

Approach Control can provide radar vectors to the approach course of a non-radar approach such as an ILS, VOR, or NDB approach. Radar vectors eliminate the need for a procedure turn and expedite the flow of traffic into the airport. If an IFR flight is given a vector for the "ILS FINAL APPROACH", the pilot should expect to assume navigation responsibility on the intermediate segment of that approach.

The controller should advise you if you will be vectored through the final approach course for sequencing or spacing. If you are nearing the course and have not been cleared for the approach and have not been instructed to turn inbound, maintain the last assigned heading and query ATC. NEVER turn inbound on the approach course unless cleared to do so.

ATC will issue clearance for the approach. When you are not on the approach course, ATC will issue an altitude to maintain until established on a segment of the approach. Radar vectors take you off the published routes so you must maintain the last assigned altitude until you are on a segment of the approach. Once established, descend to the appropriate minimum altitude for your position. Remember, MSA’s on the approach chart are emergency use altitudes and NOT appropriate for normal operations.

Pre-plan for the possibility of a circling maneuver unless the weather is down to minimums or you are operating at night. Under those conditions you will be safer landing straight-in even if you have to divert to an alternate in order to do so. Set up a safe approach speed. Maintain aircraft control by reference to the flight instruments. Use outside references while circling for position and heading information. Do not descend below the MDA until in a position to assure a normal descent to landing. Use minimums for the next higher category if airspeed so dictates. And if in doubt, execute a missed approach.

If visual reference is lost while circling to land from an instrument approach, the missed approach specified for the procedure must be followed. Since the circle-to-land maneuver can be accomplished in any direction, different patterns will be required to execute the missed approach, depending on where the airplane is when visual reference is lost.   In any case, the intital turn when executing a missed approach while circling-to-land should always be made towards the airport.

Figure Eighteen shows two examples of patterns that will keep the aircraft within the obstacle clearance area, while maneuvering to re-enter the published procedure. Note that the initial climbing turn is toward the airport, or landing runway. Now, let’s elaborate on those missed approach procedures in general.

The missed approach segment is initiated at the decision height in precision approaches, and at a specified point, usually the end of the runway, on non-precision approaches. The obstacle clearance plane for the missed approach segment is based on the assumption that the pilot initiates the missed approach at the point specified on the chart. There is no consideration given to obstacle clearance if the turn is made early. Therefore, if the pilot decides early to execute a missed approach, he should fly the procedures specified on the chart to the missed approach point, at or above the MDA or DH, before executing any turning maneuver.

Many times ATC will issue alternate missed approach procedures, especially in a radar environment. These instructions supersede the published procedure and are designed to expedite traffic.

A missed approach with stated intentions is one of the compulsory reports. The organized pilot will be aware of what his options are. A common misconception is that if a missed approach is executed, the pilot must go to the alternate he designated on his flight plan. With the system today, the controller doesn’t even know what the alternate is. The pilot’s request will depend on the circumstances, including available fuel.

The FARs also define standard alternate minimums. If the airport has a precision approach installation, and the aircraft is equipped to utilize it, then the forecast at the ETA for the airport must be at least a six hundred foot ceiling, and two miles visibility, in order to be designated as an alternate. If the airport being considered has only non-precision facilities, then the forecast must be for at least eight hundred and two. If the alternate minimums for an airport are non-standard, NOS charts use a symbol, an inverted triangle with an "A" to notify the pilot that non-standard minimums apply. Jeppesen prints this information on the airport diagram page.

The inoperative components, or visual aids table, specifies changes in visibility credit, allowed for the various types of approach light systems.

CONTACT AND VISUAL APPROACHES
Media File: | Contact and Visual Approach Criteria |

Two IFR approaches that don’t follow a published procedure are the Contact and Visual approaches, shown in Figure Eighteen. The contact approach is an approach to an airport that has a published procedure and an approved weather observer—where an aircraft on an IFR flight plan, operating clear of clouds with at least one mile visibility, and having received ATC authorization, may deviate from the prescribed procedure and proceed to the destination airport by visual reference to the surface.

The contact approach can be requested before or at any time during an instrument approach. It must be initiated by the pilot and authorized by ATC. It cannot be initiated by ATC. In the event that the required weather conditions cannot be maintained, or visual ground contact, the published missed approach procedure is negotiated.

ATC provides separation from other IFR and special VFR aircraft, but the pilot is responsible for obstruction clearance. The contact approach is sometimes a useful tool at controlled airports where special VFR flight is prohibited.

The visual approach is basically a procedure that is used at major airports in VMC, that is, Visual Meteorological Conditions or conditions that allow you to maintain required cloud clearances and visibilities. So, to be vectored for a visual approach, the ceiling is required to be 500 feet above the Minimum Vectoring Altitude or MVA.

A visual approach allows traffic to be expedited and reduces controller workload by eliminating the need for each arriving aircraft to negotiate the published procedure. As with DPs and STARs, ATC may issue a clearance for a visual approach without prior pilot request. Visual approaches may be issued for either controlled or uncontrolled airports.  

Again, reported weather must allow an aircraft flying at the minimum vectoring altitude to be in VFR weather conditions. If weather reporting service is not available at the airport, the controller may ask you if you can accept a visual approach.

ATC will not clear you for a visual approach until you report the airport or the traffic you are to follow in sight. You accept separation and wake turbulence avoidance responsibility when you accept a visual approach clearance.

You may cancel your IFR flight plan anytime you are flying in VFR conditions (except in Class A Airspace).

Your IFR flight plan is automatically cancelled by the control tower upon landing at your destination. When landing at an airport not being served by an operating control tower, the pilot must close the flight plan. This can be done by radio directly with ATC if weather conditions permit you to continue under VFR. If you can not maintain VFR cloud separation, or do not have the required visibility for VFR you must wait until after landing and then contact the nearest FSS or ATC facility by radio or telephone as soon as possible.

EMERGENCY PROCEDURES

An emergency, like beauty, is to a great degree, in the eye of the beholder. Some pilots can make an emergency out of a mag check, while others, if they lost a wing would merely request a lower altitude. Your idea of what constitutes an emergency is going to change as your level of proficiency improves and you gain experience. But whatever your level of experience, if you think you have an emergency, you probably do. Don't feel embarrassed. Confess your problem and ask for help. Declaring an emergency is what the controller needs to hear from you before he can give you priority treatment.

There isn't any way to list and plan for every possible emergency. Your training is designed to give you basic procedures in the types of trouble that most often occur and this, combined with good judgment, should give you the insight to cope with any situation that you might encounter. There are also rules, regulations, and recommended good operating procedures that you must know so that, should certain situations occur, you will know what ATC expects you to do.

Many minor emergencies have turned into major emergencies, because the pilot allowed himself to be distracted from his primary job of flying the airplane. Early detection will keep minor emergencies from becoming major emergencies. An instrument scan that includes the ammeter, engine instruments, and the vacuum gage as well as the flight instruments will provide the necessary early detection that will allow a proactive response such as landing at an airport short of your destination before systems begin to fail.

Discuss with your student normal errors in instruments and systems that result in incorrect indications. The installation error in the pitot-static system for example will result in the airspeed pointer showing a speed less than the minimum limit of the white arc when practicing power-off stalls with full flaps. This is normal and should not raise concern.

NAVIGATION EQUIPMENT MALFUNCTION

A failure of any of your navigation instruments may impair your ability to navigate and may affect the kinds of instrument approaches you will be able to conduct. The failure of one of the VORs in a dual VOR installation may be inconvenient, but it probably will not impair the remainder of your flight. The failure of an ADF radio will probably not affect the enroute portion of your flight, but will obviously prevent you from making an NDB approach. A failed glide slope or marker beacon receiver will affect your approach procedures, but will not prevent an instrument approach.

The VOR CDI and GS indicators have "OFF" flags which will warn you that a usable signal is not being received. Obviously, these instruments cannot be used for an approach if the OFF flag is showing. While the ADF and the marker beacons do not have an "off" flag, they can be tested for proper indications.

Another safeguard when using NAV receivers is to always tune and identify the station to make sure that it is transmitting the proper identifier, which means that the station is up and working.

You must notify ATC anytime you have the loss of navigational capacity.

INSTRUMENT AND INSTRUMENT SYSTEMS MALFUNCTION

The major hazard of completely trusting your instruments, as you must for instrument flying, is that they can fail. Yet the redundancy of the information that the instruments provide, not to mention the redundancy of the systems that power the instruments, will provide backup information that will allow you to detect a failed instrument.

VACUUM FAILURE - In most general aviation airplanes, the vacuum pump drives the attitude indicator and the heading indicator. Should the pump fail, these are the instruments you would lose, leaving you with only partial panel instrumentation. When the pump fails the instruments begin to spin down and their indications become unusable. Because it takes a while for the gyros to spin down, it will not immediately be obvious that the instruments have failed. These instruments do not normally have an "off" flag and, unless you notice that the vacuum gauge is reading out of the green, your instrument indications will be quite confusing. However, there are always at least two other instruments which provide pitch and bank information, even when the vacuum instruments have failed. Therefore let the instruments "vote" on which is accurate and which has failed by majority rule.

Assuming you are in IFR weather conditions when the vacuum pump fails, the preferred order of action is:

1. Radar vectors to VFR conditions nearby.
2. If ceilings are high enough, clearance for an enroute descent to VFR conditions.
3. Radar vectors to the nearest airport where a "no-gyro" ASR approach is available.
4. If your proficiency is high enough, an instrument approach to the nearest available airport. If you do not have to fly a partial panel approach do not do so.

PITOT-STATIC SYSTEM PROBLEMS - Blockage of the pitot tube or static vent will cause erroneous indications on the pressure instruments. If ice blocks the pitot tube, the ram pressure will vent through the drain hole, causing the airspeed indicator to drop to zero. In severe icing conditions, the pitot opening and drain hole may become blocked. The trapped ram pressure will cause the airspeed indication to act like an altimeter and remain the same during level flight even if large power changes are made. A climb will result in an increasing airspeed indication. A descent will result in a decreasing airspeed indication. Activating pitot heat should solve the problem.

Blockage of the static vent will render the altimeter and vertical speed indicator inoperative. Unless corrected, the airspeed indication will decrease during a climb and increase during a descent. If the aircraft is so equipped, activate the alternate static source. If not equipped with an alternate static source, break the glass on the VSI. Remember, however, that now the airspeed and altimeter read high and, if not damaged, the VSI indications are reversed.

RADIO COMMUNICATIONS FAILURE

If anytime during a flight in IMC, you are unable to contact a controller:

1. Go back to the last assigned frequency - if no contact,
2. Go to the FSS frequency - if no contact, 
3. Go to 121.5 MHz - if no contact, 
4. Listen on the appropriate NAV frequency (your NAV radios may work even when your COM radios don't) - if no contact, Continue to broadcast your intentions in the blind on 121.5 (you may still be able to transmit even though you cannot receive).

Of course, before you have gotten to this point, you will have made sure that the audio panel is set up correctly. Also, make sure you do not have a stuck microphone. A stuck mic will mute the receive function of the transmitters. If you are using the speaker, plug in a headset. It operates on a different circuit than the speaker and may solve the problem. If you are using a headset, try the speaker function.

Once you have definitely established that you have a total communications failure, adjust your transponder to code 7600.

If VFR conditions are encountered enroute, remain VFR, land as soon as practical, and notify ATC once on the ground. While in IFR conditions you must proceed on to your destination based on these priorities.

ROUTE - Follow in this order:

1. The last assigned route.
2. If being radar vectored, go direct to the fix or airway to which you were being vectored.
3. A route ATC advised you to expect at a later point.
4. The route you filed in your flight plan.

ALTITUDE - Maintain the highest of:

1. Last assigned altitude.
2. The airway MEA.
3. Expected higher altitude.

WHEN TO LEAVE A HOLD - If two-way radio communication failure occurs while holding at a holding fix which is not the approach fix, depart the hold fix at the EFC time.

WHEN TO BEGIN THE APPROACH - Unless you have received specific holding instructions that included an EFC, proceed all the way to your destination. When the clearance limit is a fix from which an approach begins, begin your descent and/or approach as close as possible to the estimated time of arrival as calculated from the filed or amended estimated time enroute. If you arrive prior to your ETA, hold at the facility or fix which is the most convenient IAF for the approach you have chosen to use. While you can choose any approach you want, your preflight weather briefing provided you with the forecast winds at your ETA. Unless they were forecast to be light, you will probably want to pick an approach that is appropriate for the forecast winds. You also probably want to choose an ILS, if one is available. You will want the lowest minimums available to reduce any chance of having to make a missed approach and proceed on to an alternate.

If the IAF over which you will hold is also the FAF, hold on the approach course, on the procedure turn side, or as published if different. You must remain in the hold, at the altitude you arrived at the fix, until your ETA. (Make it a habit to always record your time off the departure runway, so that you will be able to compute your ETA, which is based on your flight plan ETE.) When you reach your ETA, you may descend, if necessary, in the holding pattern to arrive at the glide slope intercept altitude and then make a straight-in approach from the hold.

If you arrive at your destination after your ETA, you may immediately begin the approach. If you must loose altitude, this can be done in a holding pattern as described above or during a full instrument approach procedure.

AIRPLANE SYSTEMS MALFUNCTION

The best defense against mechanical malfunctions is a good maintenance program, preflight inspection, and engine run-up. However, even the best of these inspections will not guarantee trouble free operation of all aircraft systems. While in flight, the most helpful thing you can do is to make sure that your scan includes the engine and electrical instruments. Many failures give some advanced warning. A few minutes warning can make the difference in the outcome of a problem. If you notice that the engine oil temperature is increasing, you can keep on top of the situation and make contingency plans. You may decide, based on the instrument indications, to make a precautionary landing, or divert from your destination airport to one nearer by.

While the airplane system instruments are not scanned as often as the flight instruments, not very many minutes ought to go by without checking these instruments.

ELECTRICAL SYSTEM FAILURE - Electrical failures are not always initially total or complete. Many electrical failures occur over time. The most common cause of electrical failure is the loss of an alternator. Even with a complete alternator failure, the battery will continue to supply power to the airplane's electrical systems for a period of time. It is obvious, however, that it is to your advantage to detect a failed alternator as soon as possible. This will allow you to reduce the electrical load and save power.

There are several ways to detect a failed alternator. Many aircraft have a low voltage light that illuminates whenever the system voltage drops below a certain level. In the absence of a warning light, the ammeter will show that the battery is discharging, a sign that the alternator has failed or is not supporting the electrical load on the system.

If the low voltage light does come on, follow the manufacture's emergency checklist for this condition. The low voltage light does not always mean that the alternator has failed. Sometimes the alternator is knocked off line and can be brought back on line simply by recycling the alternator.

A total and complete electrical failure has some serious consequences. Not only will you be without communications ability, you also will be without navigation ability, and even if you manage to come near your destination, you would not have the means to conduct an instrument approach. In addition to these problems, your turn coordinator will be inoperative. Interior and exterior lights will be off. You may be without flaps and the gear will have to be manually operated. Your only hope in the event of a total and complete electrical failure is to have gotten a good preflight weather briefing and know where to find VFR weather. There are no regulations to cover the procedures for a complete electrical failure.

Because of the possible serious consequences of such an event, it is important that all the gauges be included in your scan to detect a problem as early as possible, in order that you can take positive action while you still have some options available.

ENGINE FAILURE (SINGLE ENGINE) - Assuming that a restart is impossible you should:

1. Trim for the best glide speed (remember that you will be on partial panel). 2. Notify ATC. Request the nearest weather information. 3. Turn into the last known wind if able. 4. Limit the electrical load. 5. Upon breaking out of the clouds, pick a place to land and perform the emergency landing procedures of turning off your fuel supply, opening the doors, turning off the master switch, and whatever else your manufacturer's emergency checklist calls for.

SUMMARY

During your training, the emergency conditions that are discussed and practiced, to the extent possible, are often "worst case". In reality, if emergencies occur, they are often not the worst case. For example, engine failures are not always compete failures, some power may be available, enough to still fly at reduced power. Communication failures are rarely total failures. However, if you learn these lessons well, you will be as prepared as possible to handle the emergencies which may arise.

GLOBAL POSITIONING SYSTEM

GPS is a U.S. satellite-based radio navigational, positioning, and time transfer system operated by the Department of Defense (DoD). The system provides highly accurate position and velocity information and precise time on a continuous global basis to an unlimited number of properly equipped users. The system is unaffected by weather and provides a worldwide common grid reference system based on the earth-fixed coordinate system. For its earth model, GPS uses the World Geodetic System of 1984 (WGS-84) datum.

GPS provides two levels of service: Standard Positioning Service (SPS) and Precise Positioning Service (PPS). SPS provides, to all users, horizontal positioning accuracy of 100 meters, or less, with a probability of 95 percent and 300 meters with a probability of 99.99 percent. PPS is more accurate than SPS; however, this is limited to authorized U.S. and allied military, federal government, and civil users who can satisfy specific U.S. requirements.

GPS operation is based on the concept of ranging and triangulation from a group of satellites in space which act as precise reference points. A GPS receiver measures distance from a satellite using the travel time of a radio signal. Each satellite transmits a specific code, called a coarse acquisition (C/A) code, which contains information on the satellite's position, the GPS system time, and the health and accuracy of the transmitted data. Knowing the speed at which the signal traveled (approximately 186,000 miles per second) and the exact broadcast time, the distance traveled by the signal can be computed from the arrival time.

The GPS receiver matches each satellite's C/A code with an identical copy of the code contained in the receiver's data base. By shifting its copy of the satellite's code in a matching process, and by comparing this shift with its internal clock, the receiver can calculate how long it took the signal to travel from the satellite to the receiver. The distance derived from this method of computing distance is called a pseudo-range because it is not a direct measurement of distance, but a measurement based on time. Pseudo-range is subject to several error sources; for example: ionospheric and tropospheric delays and multipath.

In addition to knowing the distance to a satellite a receiver needs to know the satellite's exact position in space; this is known as its ephemeris. Each satellite transmits information about its exact orbital location. The GPS receiver uses this information to precisely establish the position of the satellite.

Using the calculated pseudo-range and position information supplied by the satellite, the GPS receiver mathematically determines its position by triangulation. The GPS receiver needs at least four satellites to yield a three-dimensional position (latitude, longitude, and altitude) and time solution. The GPS receiver computes navigational values such as distance and bearing to a waypoint, ground speed, etc., by using the aircraft's known latitude/longitude and referencing these to a data base built into the receiver.

The GPS constellation of 24 satellites is designed so that a minimum of five are always observable by a user anywhere on earth. The receiver uses data from a minimum of four satellites above the mask angle (the lowest angle above the horizon at which it can use a satellite).

The GPS receiver verifies the integrity (usability) of the signals received from the GPS constellation through receiver autonomous integrity monitoring (RAIM) to determine if a satellite is providing corrupted information. At least one satellite, in addition to those required for navigation, must be in view for the receiver to perform the RAIM function; thus, RAIM needs a minimum of 5 satellites in view, or 4 satellites and a barometric altimeter (baro-aiding) to detect an integrity anomaly. For receivers capable of doing so, RAIM needs 6 satellites in view (or 5 satellites with baro-aiding) to isolate the corrupt satellite signal and remove it from the navigation solution. Baro-aiding is a method of augmenting the GPS integrity solution by using a nonsatellite input source. GPS derived altitude should not be relied upon to determine aircraft altitude since the vertical error can be quite large. To ensure that baro-aiding is available, the current altimeter setting must be entered into the receiver as described in the operating manual.

RAIM messages vary somewhat between receivers; however, generally there are two types. One type indicates that there are not enough satellites available to provide RAIM integrity monitoring and another type indicates that the RAIM integrity monitor has detected a potential error that exceeds the limit for the current phase of flight. Without RAIM capability, the pilot has no assurance of the accuracy of the GPS position.

The DOD declared initial operational capability (IOC) of the U.S. GPS on December 8, 1993. The FAA has granted approval for U.S. civil operators to use properly certified GPS equipment as a primary means of navigation in oceanic airspace and certain remote areas. Properly certified GPS equipment may be used as a supplemental means of IFR navigation for domestic en route, terminal operations, and certain instrument approach procedures (IAP's). This approval permits the use of GPS in a manner that is consistent with current navigation requirements as well as approved air carrier operations specifications.

DEFINITIONS AND ABBREVIATIONS

Active Waypoint — The waypoint to/from which navigational guidance is being provided.

Along Track Distance (ATD) Fix — A distance in nautical miles (NM) to the active waypoint along the specified track An ATD fix will not be used where a course change is made.

Course Set — Guidance set from information provided by the GPS equipment that assists the pilot in navigating to or from an active waypoint on a heading/bearing.

Data Agency — An agency, public or private, other than a publisher of government source documents, who compiles official document information into charts or electronic formats for cockpit use.

Dead Reckoning (DR) — The navigation of an aircraft solely by means of computations based on airspeed, course, heading, wind direction and speed, ground speed, and elapsed time.

Direct To — A method used with the GPS equipment to provide the necessary course from the present position directly to a selected waypoint.

Fly By Waypoint — A waypoint that permits turn anticipation and does not require the aircraft to pass directly over it.

Fly Over Waypoint — A waypoint that requires the aircraft to pass directly over it.

Instrument Approach Waypoints — Geographical positions, specified in latitude/longitude used in defining GPS instrument approach procedures, including the initial approach waypoint, the intermediate waypoint, the final approach waypoint, the missed approach waypoint, and the missed approach holding waypoint.

NAS --- National Airspace System.

Receiver Autonomous Integrity Monitoring (RAIM) — A technique whereby a GPS receiver determines the integrity of the GPS navigation signals using only GPS signals or GPS signals augmented with altitude. At least one satellite in addition to those required for navigation must be in view for the receiver to perform RAIM function.

Sensor FAF — A final approach waypoint created and added to the database sequence of waypoints to support GPS navigation of an FAA published, no-FAF, nonprecision instrument approach procedure.

TO-FROM Navigation — RNAV equipment in which the desired path over the ground is defined as a specific course emanating either to or from a particular waypoint. The equipment functions like a conventional VOR receiver where the CDI needle and the "to/from" indicator respond to the movement of the OBS. With this equipment, the aircraft may fly either TO or FROM any single designated waypoint.

TO-TO Navigation — RNAV equipment in which a path is computed that connects two waypoints. With this equipment, two waypoints must always be available, and the aircraft is usually flying between the two waypoints and TO the active waypoint. The CDI functions like it is tracking a localizer signal; that is movement of the OBS has no effect on the CDI needle or the "to/from" indicator.

Turn Anticipation — The capability of RNAV systems to determine the point along a course, prior to a turn waypoint, where a turn should be initiated to provide a smooth path to intercept the succeeding course within the protected airspace, and to enunciate the information to the pilot.

User-selectable Navigation Database — A navigation database having user-defined contents accessible by the pilot and/or the navigation computer during aircraft operations in support of navigation needs. The database is stored electronically and is typically updated at regular intervals. It does not include data that can be entered manually by the pilot or operator.

Waypoint — A predetermined geographical position used for route definition and/or progress reporting purposes that is defined by latitude/longitude.

Before conducting IFR operations utilizing GPS, the pilot must determine whether a GPS installation is approved for use under IFR by refering to the FAA-approved Airplane Flight Manual supplement. The equipment should be operated in accordance with the provisions of the applicable AFM including the specific start-up and self-test procedures for the GPS receiver. All pilots must be thoroughly familiar with the GPS equipment installed in the aircraft and its limitations.

Prior to any GPS IFR operation, the pilot should review the appropriate NOTAMs. NOTAMs will be issued to announce outages for specific GPS satellite vehicles, by pseudo random noise (PRN) number and satellite vehicle number (SVN). GPS NOTAMs are issued under the identifier "GPS". Pilots may obtain GPS NOTAM information by request to the FSS briefer or by requesting NOTAMs, using the identifier "GPS", through the Direct User Access Terminal System (DUATS). Pilots should review the NOTAMs for the underlying approach procedure. When executing a Phase II approach, pilots should ensure the ground-based facilities upon which the approach is based are operational. If an approach is not authorized due to an inoperative navigation facility, the associated Phase II GPS approach is not authorized.

The pilot must select the appropriate airport(s), runway/approach procedure, and initial approach fix on the aircraft's GPS receiver to determine RAIM integrity for that approach. Air Traffic Control specialists are not provided any information about the operational integrity of the system. This is especially important when the pilot has been "Cleared for the Approach." Procedures should be established by the pilot in the event that GPS navigation outages are predicted or occur. In these situations, the pilot should rely on other approved equipment, delay departure, or cancel the flight.

Aircraft that are navigating by GPS are considered to be RNAV-equipped aircraft and the appropriate equipment suffix should be included in the ATC flight plan. Most users should file "/G" indicating GPS and transponder with mode C. Consult the latest edition of the Aeronautical Information Manual (AIM) for appropriate suffix information. If the GPS avionics become inoperative, the pilot should advise ATC and amend the equipment suffix.

DOMESTIC EN ROUTE AND TERMINAL AREA IFR OPERATIONS

GPS domestic en route and terminal IFR operations can be conducted as soon as proper avionics systems are installed, provided all general requirements are met. The avionics necessary to receive all of the ground-based facilities appropriate for the route to the destination airport and any required alternate airport must be installed and operational. Ground-based facilities necessary for these routes must also be operational.

The GPS Approach Overlay Program is an authorization for pilots to use GPS avionics under IFR for flying designated nonprecision instrument approach procedures, except LOC, LDA, and simplified directional facility (SDF) procedures. These procedures are now identified by the name of the procedure and "or GPS" (e.g., VOR/DME or GPS RWY 15). Other previous types of overlays have either been converted to this format or replaced with stand-alone procedures. Only approaches contained in the current onboard navigation database are authorized. The navigation database may contain information about nonoverlay approach procedures that is intended to be used to enhance position orientation, generally by providing a map, while flying these approaches using conventional NAVAID's. This approach information should not be confused with a GPS overlay approach (see the receiver operating manual, AFM, or AFM Supplement for details on how to identify these approaches in the navigation database).

NOTE-
Overlay approaches are predicated upon the design criteria of the ground-based NAVAID used as the basis of the approach. As such, they do not adhere to the design criteria for stand-alone GPS approaches.

GPS IFR approach operations can be conducted as soon as proper avionics systems are installed and the following requirements are met:

1. The authorization to use GPS to fly instrument approaches is limited to U.S. airspace. 
2. The use of GPS in any other airspace must be expressly authorized by the FAA Administrator. 
3. GPS instrument approach operations outside the U.S. must be authorized by the appropriate sovereign authority.

Subject to the restrictions below, operators in the U.S. NAS are authorized to use GPS equipment certified for IFR operations in place of ADF and/or DME equipment for en route and terminal operations. For some operations there is no requirement for the aircraft to be equipped with an ADF or DME receiver. The ground-based NDB or DME facility may be temporarily out of service during these operations. Charting will not change to support these operations.

1. Determining the aircraft position over a DME fix. GPS satisfies the 14 CFR Section 91.205(e) requirement for DME at and above 24,000 feet mean sea level (MSL) (FL 240). 
2. Flying a DME arc. 
3. Navigating to/from an NDB/compass locator. 
4. Determining the aircraft position over an NDB/compass locator. 
5. Determining the aircraft position over a fix defined by an NDB/compass locator bearing crossing a VOR/LOC course. 
6. Holding over an NDB/compass locator.

NOTE-
This approval does not alter the conditions and requirements for use of GPS to fly existing nonprecision instrument approach procedures as defined in the GPS approach overlay program.

Restrictions

1. GPS avionics approved for terminal IFR operations may be used in lieu of ADF and/or DME. Included in this approval are both stand-alone and multi-sensor systems actively employing GPS as a sensor. This equipment must be installed in accordance with appropriate airworthiness installation requirements and the provisions of the applicable FAA approved AFM, AFM supplement, or pilot's guide must be met. The required integrity for these operations must be provided by at least en route RAIM, or an equivalent method; i.e., Wide Area Augmentation System (WAAS). 
2. For air carriers and operators for compensation or hire, Principal Operations Inspector (POI) and operations specification approval is required for any use of GPS. 
3. Waypoints, fixes, intersections, and facility locations to be used for these operations must be retrieved from the GPS airborne database. The database must be current. If the required positions cannot be retrieved from the airborne database, the substitution of GPS for ADF and/or DME is not authorized. 
4. The aircraft GPS system must be operated within the guidelines contained in the AFM, AFM supplement, or pilot's guide. 
5. The CDI must be set to terminal sensitivity (normally 1 or 1 1/4 NM) when tracking GPS course guidance in the terminal area. This is to ensure that small deviations from course are displayed to the pilot in order to keep the aircraft within the smaller terminal protected areas. 
6. Charted requirements for ADF and/or DME can be met using the GPS system, except for use as the principal instrument approach navigation source. 
7. Procedures must be established for use in the event that GPS integrity outages are predicted or occur (RAIM annunciation). In these situations, the flight must rely on other approved equipment; this may require the aircraft to be equipped with operational NDB and/or DME receivers. Otherwise, the flight must be rerouted, delayed, canceled or conducted VFR. 
8. A non-GPS approach procedure must exist at the alternate airport when one is required. If the non-GPS approaches on which the pilot must rely require DME or ADF, the aircraft must be equipped with DME or ADF avionics as appropriate.

Guidance. The following provides general guidance which is not specific to any particular aircraft GPS system. For specific system guidance refer to the AFM, AFM supplement, pilot's guide, or contact the manufacturer of your system.

1. To determine the aircraft position over a DME fix:

(a)Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) If the fix is identified by a five letter name which is contained in the GPS airborne database, you may select either the named fix as the active GPS waypoint (WP) or the facility establishing the DME fix as the active GPS WP.

NOTE-
When using a facility as the active WP, the only acceptable facility is the DME facility which is charted as the one used to establish the DME fix. If this facility is not in your airborne database, you are not authorized to use a facility WP for this operation.

(c) If the fix is identified by a five letter name which is not contained in the GPS airborne database, or if the fix is not named, you must select the facility establishing the DME fix or another named DME fix as the active GPS WP.

NOTE-
An alternative, until all DME sources are in the database, is using a named DME fix as the active waypoint to identify unnamed DME fixes on the same course and from the same DME source as the active waypoint.

CAUTION-
Pilots should be extremely careful to ensure that correct distance measurements are used when utilizing this interim method. It is strongly recommended that pilots review distances for DME fixing during preflight preparation.

(d) If you select the named fix as your active GPS WP, you are over the fix when the GPS system indicates you are at the active WP.

(e) If you select the DME providing facility as the active GPS WP, you are over the fix when the GPS distance from the active WP equals the charted DME value and you are on the appropriate bearing or course.

      2. To fly a DME arc:

(a) Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) You must select, from the airborne database, the facility providing the DME arc as the active GPS WP.

NOTE-
The only acceptable facility is the DME facility on which the arc is based. If this facility is not in your airborne database, you are not authorized to perform this operation.

(c) Maintain position on the arc by reference to the GPS distance in lieu of a DME readout.

      3. To navigate to or from an NDB/compass locator:

NOTE-
If the chart depicts the compass locator collocated with a fix of the same name, use of that fix as the active WP in place of the compass locator facility is authorized.

(a) Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) Select terminal CDI sensitivity in accordance with the AFM, AFM supplement, or pilot's guide if in the terminal area.

(c) Select the NDB/compass locator facility from the airborne database as the active WP.

(d) Select and navigate on the appropriate course to or from the active WP.

      4.  To determine the aircraft position over an NDB/compass locator:

(a) Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) Select the NDB/compass locator facility from the airborne database as the active WP.

NOTE-
When using an NDB/compass locator, that facility must be charted and be in the airborne database. If this facility is not in your airborne database, you are not authorized to use a facility WP for this operation.

(c) You are over the NDB/compass locator when the GPS system indicates you are at the active WP.

5. To determine the position over a fix made up of an NDB/compass locator bearing crossing a VOR/LOC course:

(a) Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) A fix made up by a crossing NDB/compass locator bearing will be identified by a five letter fix name. You may select either the named fix or the NDB/compass locator facility providing the crossing bearing to establish the fix as the active GPS WP.

NOTE-
When using an NDB/compass locator, that facility must be charted and be in the airborne database. If this facility is not in your airborne database, you are not authorized to use a facility WP for this operation.

(c) If you select the named fix as your active GPS WP, you are over the fix when the GPS system indicates you are at the WP as you fly the prescribed track from the non-GPS navigation source.

(d) If you select the NDB/compass locator facility as the active GPS WP, you are over the fix when the GPS bearing to the active WP is the same as the charted NDB/compass locator bearing for the fix as you fly the prescribed track from the non-GPS navigation source.

      6. To hold over an NDB/compass locator:

(a) Verify aircraft GPS system integrity monitoring is functioning properly and indicates satisfactory integrity.

(b) Select terminal CDI sensitivity in accordance with the AFM, AFM supplement, or pilot's guide if in the terminal area.

(c) Select the NDB/compass locator facility from the airborne database as the active WP.

NOTE-
When using a facility as the active WP, the only acceptable facility is the NDB/compass locator facility which is charted. If this facility is not in your airborne database, you are not authorized to use a facility WP for this operation.

(d) Select nonsequencing (e.g. "HOLD" or "OBS") mode and the appropriate course in accordance with the AFM, AFM supplement, or pilot's guide.

(e) Hold using the GPS system in accordance with the AFM, AFM supplement, or pilot's guide.

Planning. Good advance planning and intimate knowledge of your navigational systems are vital to safe and successful use of GPS in lieu of ADF and/or DME.

(a) You should plan ahead before using GPS systems as a substitute for ADF and/or DME. You will have several alternatives in selecting waypoints and system configuration. After you are cleared for the approach is not the time to begin programming your GPS. In the flight planning process you should determine whether you will use the equipment in the automatic sequencing mode or in the nonsequencing mode and select the waypoints you will use.

(b) When you are using your aircraft GPS system to supplement other navigation systems, you may need to bring your GPS control panel into your navigation scan to see the GPS information. Some GPS aircraft installations will present localizer information on the CDI whenever a localizer frequency is tuned, removing the GPS information from the CDI display. Good advance planning and intimate knowledge of your navigation systems are vital to safe and successful use of GPS.

(c) The following are some factors to consider when preparing to install a GPS receiver in an aircraft. Installation of the equipment can determine how easy or how difficult it will be to use the system.

(1) Consideration should be given to installing the receiver within the primary instrument scan to facilitate using the GPS in lieu of ADF and/or DME. This will preclude breaking the primary instrument scan while flying the aircraft and tuning, and identifying waypoints. This becomes increasingly important on approaches, and missed approaches.

(2) Many GPS receivers can drive an ADF type bearing pointer. Such an installation will provide the pilot with an enhanced level of situational awareness by providing GPS navigation information while the CDI is set to VOR or ILS.

(3) The GPS receiver may be installed so that when an ILS frequency is tuned, the navigation display defaults to the VOR/ILS mode, preempting the GPS mode. However, if the receiver installation requires a manual selection from GPS to ILS, it allows the ILS to be tuned and identified while navigating on the GPS. Additionally, this prevents the navigation display from automatically switching back to GPS when a VOR frequency is selected. If the navigation display automatically switches to GPS mode when a VOR is selected, the change may go unnoticed and could result in erroneous navigation and departing obstruction protected airspace.

(4) GPS is a supplemental navigation system in part due to signal availability. There will be times when your system will not receive enough satellites with proper geometry to provide accurate positioning or sufficient integrity. Procedures should be established by the pilot in the event that GPS outages occur. In these situations, the pilot should rely on other approved equipment, delay departure, reroute, or discontinue IFR operations.

APPROACH PROCEDURES

Equipment and Database Requirements

Authorization to fly approaches under IFR using GPS avionics systems requires that:

(a) A pilot use a GPS approved for IFR terminal procedures. (Check the FAA approved Airplane Flight Manual supplement.); and

(b) All approach procedures to be flown must be retrievable from the current airborne navigation database supplied by the equipment manufacturer or other FAA approved source.

Flying GPS Approaches

Pilots should "arm" or enable the GPS approach mode prior to the IAF and fly the full approach from an Initial Approach Waypoint (IAWP) or feeder fix unless specifically cleared otherwise. Randomly joining an approach at an intermediate fix does not assure terrain clearance.

When an approach has been loaded in the flight plan, GPS receivers will give an "arm" annunciation 30 NM straight line distance from the airport/heliport reference point. Pilots should arm the approach mode at this time, if it has not already been armed (some receivers arm automatically). Without arming, the receiver will not change from en route CDI and RAIM sensitivity of ±5 NM either side of centerline to ±1 NM terminal sensitivity. Where the IAWP is inside this 30 mile point, a CDI sensitivity change will occur once the approach mode is armed and the aircraft is inside 30 NM. Where the IAWP is beyond 30 NM from the airport/heliport reference point, CDI sensitivity will not change until the aircraft is within 30 miles of the airport/heliport reference point even if the approach is armed earlier. Feeder route obstacle clearance is predicated on the receiver being in terminal (±1 NM) CDI sensitivity and RAIM within 30 NM of the airport/heliport reference point, therefore, the receiver should always be armed (if required) not later than the 30 NM annunciation.

The pilot must be aware of what bank angle/turn rate the particular receiver uses to compute turn anticipation, and whether wind and airspeed are included in the receiver's calculations. This information should be in the receiver operating manual. Over or under banking the turn onto the final approach course may significantly delay getting on course and may result in high descent rates to achieve the next segment altitude.

When within 2 NM of the FAWP with the approach mode armed, the approach mode will switch to active, which results in RAIM changing to approach sensitivity and a change in CDI sensitivity. Beginning 2 NM prior to the FAWP, the full scale CDI sensitivity will smoothly change from ±1 NM to ±0.3 NM at the FAWP. As sensitivity changes from ±1 NM to ±0.3 NM approaching the FAWP, with the CDI not centered, the corresponding increase in CDI displacement may give the impression that the aircraft is moving further away from the intended course even though it is on an acceptable intercept heading. Referencing the digital track displacement information (cross track error), if it is available in the approach mode, may help the pilot remain position oriented in this situation. Being established on the final approach course prior to the beginning of the sensitivity change at 2 NM will help prevent problems in interpreting the CDI display during ramp down. Therefore, requesting or accepting vectors which will cause the aircraft to intercept the final approach course within 2 NM of the FAWP is not recommended.

When receiving vectors to final, most receiver operating manuals suggest placing the receiver in the nonsequencing mode on the FAWP and manually setting the course. This provides an extended final approach course in cases where the aircraft is vectored onto the final approach course outside of any existing segment which is aligned with the runway. Assigned altitudes must be maintained until established on a published segment of the approach. Required altitudes at waypoints outside the FAWP or stepdown fixes must be considered. Calculating the distance to the FAWP may be required in order to descend at the proper location.

Overriding an automatically selected sensitivity during an approach will cancel the approach mode annunciation. If the approach mode is not armed by 2 NM prior to the FAWP, the approach mode will not become active at 2 NM prior to the FAWP, and the equipment will flag. In these conditions, the RAIM and CDI sensitivity will not ramp down, and the pilot should not descend to MDA, but fly to the MAWP and execute a missed approach. The approach active annunciator and/or the receiver should be checked to ensure the approach mode is active prior to the FAWP.

Do not attempt to fly an approach unless the procedure is contained in the current, on-board navigation database and identified as "GPS" on the approach chart. GPS approaches are normally designed to eliminate inefficient and time consuming course reversals such as procedure turns and holding patterns. Waypoint sequencing is automatic and may have to be disabled by the pilot in the event that a course reversal becomes necessary.

The navigation database may contain information about nonoverlay approach procedures that is intended to be used to enhance position orientation, generally by providing a map, while flying these approaches using conventional NAVAID's. This approach information should not be confused with a GPS overlay approach (see the receiver operating manual, AFM, or AFM Supplement for details on how to identify these procedures in the navigation database). Flying point to point on the approach does not assure compliance with the published approach procedure. The proper RAIM sensitivity will not be available and the CDI sensitivity will not automatically change to ±0.3 NM. Manually setting CDI sensitivity does not automatically change the RAIM sensitivity on some receivers. Some existing nonprecision approach procedures cannot be coded for use with GPS and will not be available as overlays.

Pilots should pay particular attention to the exact operation of their GPS receivers for performing holding patterns and in the case of overlay approaches, operations such as procedure turns. These procedures may require manual intervention by the pilot to stop the sequencing of waypoints by the receiver and to resume automatic GPS navigation sequencing once the maneuver is complete. The same waypoint may appear in the route of flight more than once consecutively (e.g., IAWP, FAWP, MAHWP on a procedure turn). Care must be exercised to ensure that the receiver is sequenced to the appropriate waypoint for the segment of the procedure being flown, especially if one or more fly-overs are skipped (e.g., FAWP rather than IAWP if the procedure turn is not flown). The pilot may have to sequence past one or more fly-overs of the same waypoint in order to start GPS automatic sequencing at the proper place in the sequence of waypoints.

Incorrect inputs into the GPS receiver are especially critical during approaches. In some cases, an incorrect entry can cause the receiver to leave the approach mode.

A fix on an overlay approach identified by a DME fix will not be in the waypoint sequence on the GPS receiver unless there is a published name assigned to it. When a name is assigned, the along track to the waypoint may be zero rather than the DME stated on the approach chart. The pilot should be alert for this on any overlay procedure where the original approach used DME.

If a visual descent point (VDP) is published, it will not be included in the sequence of waypoints. Pilots are expected to use normal piloting techniques for beginning the visual descent, such as ATD (Along Track Distance).

Unnamed stepdown fixes in the final approach segment will not be coded in the waypoint sequence of the aircraft's navigation database and must be identified using ATD. Stepdown fixes in the final approach segment of RNAV (GPS) approaches are being named, in addition to being identified by ATD. However, since most GPS avionics do not accommodate waypoints between the FAF and MAP, even when the waypoint is named, the waypoints for these stepdown fixes may not appear in the sequence of waypoints in the navigation database. Pilots must continue to identify these stepdown fixes using ATD.

Missed Approach

A GPS missed approach requires pilot action to sequence the receiver past the MAWP to the missed approach portion of the procedure. The pilot must be thoroughly familiar with the activation procedure for the particular GPS receiver installed in the aircraft and must initiate appropriate action after the MAWP. Activating the missed approach prior to the MAWP will cause CDI sensitivity to immediately change to terminal (±1NM) sensitivity and the receiver will continue to navigate to the MAWP. The receiver will not sequence past the MAWP. Turns should not begin prior to the MAWP. If the missed approach is not activated, the GPS receiver will display an extension of the inbound final approach course and the ATD will increase from the MAWP until it is manually sequenced after crossing the MAWP.

Missed approach routings in which the first track is via a course rather than direct to the next waypoint require additional action by the pilot to set the course. Being familiar with all of the inputs required is especially critical during this phase of flight.

Pilots should practice GPS approaches under visual meteorological conditions (VMC) until thoroughly proficient with all aspects of their equipment (receiver and installation) prior to attempting flight by IFR in instrument meteorological conditions (IMC). Some of the areas which the pilot should practice are:

1. Utilizing the receiver autonomous integrity monitoring (RAIM) prediction function;  
2. Inserting a DP into the flight plan, including setting terminal CDI sensitivity, if required, and the conditions under which terminal RAIM is available for departure (some receivers are not DP or STAR capable);  
3. Programming the destination airport;  
4. Programming and flying the overlay approaches (especially procedure turns and arcs);  
5. Changing to another approach after selecting an approach;  
6. Programming and flying "direct" missed approaches;  
7. Programming and flying "routed" missed approaches;  
8. Entering, flying, and exiting holding patterns, particularly on overlay approaches with a second waypoint in the holding pattern;  
9. Programming and flying a "route" from a holding pattern;  
10. Programming and flying an approach with radar vectors to the intermediate segment;  
11. Indication of the actions required for RAIM failure both before and after the FAWP; and  
12. Programming a radial and distance from a VOR (often used in departure instructions).