A crutch is a support. If you break your leg, you use a crutch until the leg heals, then you get rid of the crutch. That's how a crutch should work. If you keep the crutch after the leg heals, you will never walk as efficiently as you could without the crutch.
In flight training, crutches come in several forms. For example, mnemonic devices such as "all easterners are odd" can help students (and often instructors) remember the proper hemispherical cruising altitude for eastbound trips. Another good crutch is a checklist, needed for any complex procedure that has the potential to end in disaster. Unlike cute sayings reminding us of underlying information, though, checklist completion has been known to become a goal itself. Students must understand why they are moving a control, what the control movement causes, and what that movement should accomplish. If they follow a checklist item that says "check oil pressure" but were never taught what that pressure should be, they'll likely ignore a zero oil pressure indication and move to the next item.
Another oft-used mnemonic device is ANDS, for Accelerate North, Decelerate South. It's used to help students understand compass error while accelerating and decelerating in the northern hemisphere. If your students can correctly identify what a compass will indicate when accelerating on an easterly or westerly heading, it means that they understand the concept. On the other hand, if you ask them what ANDS means, you're just testing the crutch, which you have turned into the objective, and you have no idea if they understand compass acceleration error.
The Private Pilot Practical Test Standards have several objectives that were originally crutches, such as the rectangular course (Area VI, Task A). The procedure is to enter the course at an angle to the first leg, then fly a complete rectangular pattern. Terms such as traffic pattern altitude and 45 degrees to the downwind leg are clues that this originally was an exercise for learning traffic patterns, but somehow it became part of the private pilot checkride in addition to flying traffic patterns. It reminds me of an official document I once received from the "Department of Redundancy Department."
At this point some may ask, "What's wrong with evaluating the crutch? It's part of the objective. If a student can perform the crutch, he can perform the procedure." Sometimes this can be true, but more often it is not. In the case of the traffic pattern, a correct performance means the objective is achieved, and the crutch no longer matters. On the other hand, if a student is evaluated only on the crutch, the original objective is defeated, which makes the crutch useless since it leads nowhere. Fortunately, many (if not all) examiners observe traffic pattern procedures and evaluate the rectangular course task based on the traffic pattern.
Another less obvious example of confused objectives in the private pilot PTS is stalls (Area VIII, Tasks B and C). Stall training and evaluation has had many names over the past 30 years, including full stalls, partial stalls, imminent stalls, approach-to-landing stalls, gliding stalls, turning stalls, straight-ahead stalls, power-on stalls, power-off stalls, departure stalls, takeoff stalls, approach stalls, and accelerated stalls. Current names are power-on stalls and power-off stalls, but the procedures for these still simulate stalls after takeoff and stalls before landings. If you think you're confused at this point, think of the poor student.
Research indicates that most stall accidents occur in the traffic pattern during approach or after takeoff, hence the names "approach stall" and "takeoff stall." It makes sense to train students in specific dangerous situations that cause fatal stalls; unfortunately, stall entry procedures are taught by rote, and don't transfer well. In training, students are trying to stall the aircraft on landing or takeoff, even though on a real approach or takeoff pilots are not trying to stall. Since the "try-to-stall" activity (the stimulus) is not present in the real world, the pilot is often not ready for stall recovery (the response), and doesn't. Traffic pattern stalls should be an adjunct to stall mastery, and not the primary objective.
This last example demonstrates why identifying and teaching the real objective is so important. Instructors, don't let your learning crutches grow up to be objectives.
Jeff Falkner is an aviation training consultant and instructional media developer who teaches aeronautics at Sacramento City College. He has more than 9,000 hours of Air Force, air carrier, and general aviation flying time.
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