From the CFI #3: Practice Does Not Make Perfect

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No, we're not saying you shouldn't practice. AVweb's Linda Pendleton takes a crack at another truism of flight training, showing that practicing the wrong thing can be just as bad as not practicing.

You've heard it since you were a little kid -- we all have. The old saw "practice makes perfect" has been drummed into us by mothers, piano teachers and just about anyone else who was trying to teach us anything. I'd be willing to bet that at some time or another, a flight instructor has told you the same thing.

Now, what would you think if I told you nothing could be farther from the truth? I'm not knocking the value of practice, but the assertion that practice makes perfect. The truth is, practice makes permanent and if you want to be perfect, that's how you must practice. A bit extreme, you say? Perhaps, but very much in line with the concept of primacy, which is the thrust of this article.

Primacy

According to the FAA Handbook for Instructors primacy -- an important concept in learning -- is a principle of learning where the first experience of something often creates a strong, almost unshakable impression. The importance to an instructor and to students is that the first time something is demonstrated, it must be shown correctly, because that experience is the one most likely to be remembered by the student. Students retain information they learn for the first time longer than they retain information they must relearn. Unlearning incorrect procedures (or bad habits) is always more difficult than learning the correct procedures in the beginning.

A Horrible Example

Unfortunately, a pilot flying a Cessna 310 that departed Brackett Field in La Verne, Calif., on July 4, 2002, illustrated a horrible example of the power of primacy and the permanence of practice. This pilot and his passenger departed Brackett Field in the pilot's Cessna 310 shortly after noon on that Independence Day. The weather conditions were normal for that part of the world at that time of year: a light wind (from 250 at 7 knots), no ceiling and the visibility five miles in haze. (That's considered good VFR in Southern California. The area around the Pomona VOR and Brackett Field -- northeast of LA -- often has worse visibility than the area closer to the coast because of the prevailing westerly winds.)

Shortly after takeoff, the pilot transmitted several mayday calls to the tower at Brackett Field. Witnesses noted that the left propeller seemed to be turning more slowly than the right and that the gear was extended. Witnesses also reported unusual engine sounds -- backfiring to be precise. (But don't witnesses always report engines backfiring when there is an aviation accident -- usually sounds that are strangely reminiscent of sounds heard in movies about World War II air battles?) The aircraft impacted trees and came to rest on the bank of a reservoir in a picnic area. Both occupants of the aircraft were killed, as were two people on the ground. Nine were seriously injured.

When the cockpit area of the wreckage was examined the throttle quadrant was found to have the following settings: The left throttle control was in the mid-range setting, the left prop control was pulled aft about one inch, as was the left mixture control; the right engine controls were all in the full forward position.

On examination of the propellers, the left propeller blades were bent aft and showed very light leading edge damage. These are findings that are consistent with an engine that was not producing power at the time of impact. Damage to the right engine and propeller indicated that it was producing power at impact. As previously mentioned, the gear was extended.

So, what in the world does this all have to do with primacy? Lots -- it seems like this poor pilot had performed exactly as he was trained. The flight instructor who gave this student his multiengine training was interviewed and he stated that when practicing engine-out procedures he would retard either the throttle or mixture (depending upon altitude) and then the student was to verify the inoperative engine by reducing the throttle. The student was then to retard the propeller lever of the identified engine aft one inch to simulate feathering the propeller. The instructor would then set zero thrust on the inoperative engine. That's exactly what this student did when faced with a real engine-out emergency! He performed exactly as he was trained and it turned out to be a fatal performance. (When the engine fails in a Cessna 310, the propeller control for the failed engine must be moved all the way aft so as to feather the propeller and cause the least amount of drag.) ** Primacy is stronger than a lot of instructors give it credit for being and, as we can see, that can be a deadly mistake. True, the student neglected to retract the landing gear, but the windmilling propeller was a far greater problem than the gear -- the extended gear would not cause directional control problems.

Who was at fault here? Who knows, and it's not my job -- nor the thrust of this article -- to determine that. There was no determination as to why that engine was not producing power that day; there are some theories, but no conclusive evidence. It doesn't matter in this discussion. What does matter is that this pilot paid for training to achieve his multiengine rating and safely fly his twin. In an emergency, he performed just as he was instructed. Primacy! Had this pilot lived to fly another day, it would have taken much more instruction and a concerted effort to eradicate the previous instruction.

Learning and Emotion

Learning depends upon memory, and the strongest memories are those formed when there is a high degree of emotion involved. The more emotion, the stronger the memory. The stronger the memory, the harder it is to change or eradicate. New aviation students have a high degree of emotion involved in their learning. The sensations are new and the habits being formed are not in the normal experience for land-based primates. There is anticipation, a bit of fear, and a great deal of performance anxiety. Pilots seem to have a high degree of perfectionism, also, and so there is the desire to be able to master the concepts quickly. This all puts a great burden on the flight instructor to make sure that the habits being formed are accurate, because they certainly will be permanent.

Performance Standards and How We Teach

The FAA sets performance tolerances for the various certificates and ratings and flight instructors usually point their students to the Practical Test Standards to judge their performance against these standards. For the private pilot certificate, the altitude tolerances are plus or minus 200 feet for en route and straight and level flight. (Some maneuvers have tolerances of plus or minus 100 feet.) Has an instructor done the job if students perform to this tolerance and are able, with little exception, to keep their altitude within this 400 foot buffer? Perhaps not. Students allowed to slop around within this buffer zone will have a far more difficult time with advanced ratings, which require more precise control. They will have to spend valuable time unlearning the former tolerances (bad habits) and tightening up their aircraft control.

It has always amazed me to note that a pilot will be able to hold the assigned altitude plus 100 feet absolutely without wavering, but finds it almost impossible to maintain the exact assigned altitude. Not so strange, however, when you look at the way pilots are very often trained. We are taught that we are not out of tolerance unless we are more than 100 feet off altitude (for the instrument rating, for example) and so, any altitude error less than 100 feet is not perceived as out of tolerance and therefore not usually corrected for. What would happen if we flight instructors -- from Hour One of instruction -- insisted on absolute perfection? We'd make more precise pilots, that is for sure. Would it take those pilots longer to achieve their ratings? I doubt it. New pilots can learn to precisely control the airplane; in fact it may even be easier for them. Correcting for an error when it begins is far easier than waiting until a significant correction must be made.

An older and wiser instructor once said to me, "I can guarantee you that sometime in your aviation career, a time will come when your life will depend upon holding an exact altitude, heading or airspeed. I don't know when or why that will happen, but I do know that when it does, holding that precise parameter better be second nature because there will be too much else going on at the time to devote attention to it." I don't believe that time has come yet, but I have always remembered the admonition.

Instructors, make sure that what you teach is exactly right -- and will be right in all instances. Don't ever teach your students something that is proper only in limited circumstances. They'll remember it at the wrong time. I'm sure the 310 pilot's instructor told him that, of course, in an actual engine failure the prop lever would be pulled all the way aft to the feather position. What he had the student practice, however, was a procedure that was not valid under any circumstances. Pulling the prop lever back to the feather position will not hurt the engine if the instructor quickly moves the lever forward again. After all, the throttle has been retarded on that engine. Isn't this about the same procedure used to check the feathering on the preflight run-up?

Have your students maintain exact altitudes, headings and airspeeds. They will become accustomed to monitoring their performance for any deviations and will correct when that correction is a minor maneuver, not a major correction. Don't teach any procedures in an aircraft that will cause problems down the line. As an example, when teaching in Citations we don't let pilots retract the flaps until exiting the runway. Now, in a Citation with a crew of two that would not cause a problem, but there are other jets that have the flaps and the brakes on the same hydraulic system. Retracting the flaps has the potential of a hydraulic failure that can impact the ability to stop the airplane.

Practice Makes Permanent

When you are out practicing in an airplane, be hard on yourself. Practice perfection. Don't take the FAA tolerances -- they will set you up for failure. You will not notice small deviations and will need to spend far more time and energy making corrections than would be necessary if exact parameters were maintained. I realize that this will not come immediately -- remember, it's harder to break bad habits than it is to form good ones in the first place.

There are reasons beyond personal pride for doing this. If your altitude varies when you're at MDA on an instrument approach, that can either put you back up in the clouds and cause a missed approach, or put you in a position where you have far less obstacle clearance than you had planned on. If you are a couple of knots fast on final, so what? Well, each knot will cause your landing distance to increase by about 2%. Those 10 knots "for Ma and the kids" aren't looking so attractive now, are they? If you're too fast or slow on a non-precision approach, your timing will not work out right and that can cause a missed approach. Wandering headings on an instrument approach can cause a missed approach, and again, can also cause you to be a lot closer to terrain than you had planned.

When taking dual for additional ratings, make sure you know exactly how each maneuver and procedure is supposed to be performed and make sure that is exactly how your instructor demonstrates or teaches it. If not, find out why. There's more than just personal pride in performance involved here. As we saw above, your life could depend upon it.


For more From The CFI, check out the rest of Linda's articles.