April 1, 1997
MARC E. COOK
Pilots as a rule aren't particularly lazy. After all, the very act of piloting requires preparation, concentration, and ongoing effort; it is not, as we all know, an armchair pursuit. And yet who among us can claim that there is no room for improvement?
If you use your airplane for recreational transportation — as opposed to transportational recreation — chances are good that your usual flight includes the normal takeoff, cruise, approach, and landing phases. Outside of recurrent training, you probably don't practice anything more than your basic skills — flying smoothly, maneuvering on instruments successfully, and completing an instrument approach wherein the runway faithfully appears at decision height.
Take a look at the accident statistics and you'll see that the vast majority of landing incidents could have been prevented with good airspeed control. Let's face it, after enough flying experience — particularly in the same airplane, if you happen to be an owner — it's easy to learn the ways to "cheat" the ideal final-approach speed. The more you fly a particular airplane, it seems, the more likely you are to tack on extra — and most often unnecessary — airspeed to the approach phase.
What may well be at the root of this phenomenon is the fact that once outside of the purview of basic or recurrent training, most pilots don't go out and practice minimum-airspeed maneuvers or approaches to stalls. The prevailing thought seems to be, "Why should I? This is a traveling machine, not a pattern-pounder." And with the lack of experience at near-stall speeds — save for right over the runway, anyway — many pilots become fearful of slowing down.
But it is useful to go out and practice minimum airspeed maneuvering in your airplane, not the beater-rental you use for recurrent training. It's no surprise that a Bonanza handles differently at and near the stall speed than does the Skyhawk that you probably used for the biennial flight review. You can learn something by practicing in a simple airplane, but if your regular mount is something more sophisticated, you are getting only part of the education.
Check your handbook for the predicted stall speeds. You will want to understand that stall speeds will vary with the gross weight of the airplane; the listed numbers come at the maximum weight value. Start your maneuvering by climbing to a comfortable altitude — pick something with lots of terrain clearance; 4,000 to 6,000 feet agl ought to do it over flat terrain. (Bear in mind, also, that you will want to pick a clear, calm day for this kind of practice; trying to learn something about your airplane if you're fighting wind or weather is a doubly hard task.)
Slow the airplane to a high approach speed, say 1.5 times the clean stall speed. Because you begin almost every approach in this configuration, it will probably feel quite familiar. Try a few turns at 30 and 45 degrees of bank. Notice how the airplane responds in roll and how much additional back pressure you need to maintain altitude. Keep the airplane trimmed in pitch and look out the window. (It's not a bad idea to bring along a flying chum to help with this chore.)
Reduce the maneuvering speed by increments, to within 10 knots of the predicted stall speed. Repeat those turning maneuvers. Notice how the ailerons feel at this speed and how the controls generally feel sloppier and less authoritative. These are your cues — among others, of course — that the margin above the stall is diminishing. Through all of these maneuvers, concentrate on keeping the ball centered; coordinated flight is critical at these low airspeeds to make sure that the airplane does not depart into a spin or incipient spin.
After a few minutes of flying around with the stall horn blaring, set up for a few simple, power-off stalls. Start in the clean configuration and work on maintaining altitude by increasing the angle of attack as you slowly reduce the throttle. Some pilots don't like to fly all the way into the stall, and many flight instructors work in the realm of approach to stalls only. Here you're looking for other aerodynamic clues that the airfoil has run out of lift — shaking in the control column from separation of airflow over the inboard sections of the wing and the decaying elevator authority.
Finish the routine with a full-back-stick straight-ahead stall. (In some airplanes, you will want to be ready for a wing drop. If your airplane tries to turn upside down at the break of a coordinated stall, have the rigging checked. This is a malady that could come to smite you at an inopportune moment.)
Recover from the stall with minimal power and relaxation of back pressure; you should not have to push briskly forward on the yoke to regain flying speed. (Bear in mind, however, that in the event of a real, inadvertent stall, use every tool you have — including full power applied as quickly as possible and authoritative movement of the controls.)
Try more slow flight in varying configurations, accompanied by full stalls and recoveries.
Now that you've spent the better part of an hour wetting down the yoke and your shirt collar, take a break with some precision ground-reference maneuvers. Drop down to an altitude that affords appropriate terrain clearance and reasonable places to land should the engine quit. Pick a long road or other landmark, like a river (or, if in California, the nearest fault line) and practice your S-turns. The purpose of this maneuver, which many student pilots learn to dislike intensely, is simply to work on your coordination and flight-path prediction skills. Your aim is to cross the road with the wing parallel to it, commit your turnaround point with the wing perfectly perpendicular to the road, and keep the airplane in a constant turn throughout. With any kind of wind, this maneuver really works a pilot's skills. If you don't recall the specifics of this maneuver, grab the nearest flight instructor for a ride — he'll be happy to help.
In any event, it's important to remember that the point of these maneuvers is to knock the rust off of your basic airmanship skills, to do something out of the ordinary in your airplane, and to rekindle that feeling of "I can handle this thing." Sure beats the armchair.
Owners of high-performance airplanes — particularly those whose models have high-output or turbocharged engines — are apt to balk at committing training maneuvers in their own aircraft. These pilots will usually cite the fact that such maneuvers may well be hard on the engine.
Depends. With some forethought and care, these flight maneuvers can be no more harmful to finicky powerplants than any normal flight profile. In fact, because of the low power typically needed for such flights, the engines may well be better off. (And there are those powerplant gurus who point to the rapid heating every engine experiences on the first takeoff of the day and suggest that thermal shock belongs on the list with those hard-to-believe premises from X-Files episodes.) Here are some tips for making maneuvering flight easier on your engine.
Once up to the altitude you plan to use for low-airspeed practice, take your time in letting the engine cool at a low cruise setting. Use this time to make your clearing turns. In the transition to low speed and in dirtying up the airplane — if applicable — try to make the power changes gradual. Once the airplane is slowed and the engine cooled, however, there's little risk of thermal-shock-induced damage. Just make sure that any stall recoveries are made with gradual power increases, paying particular attention to mixture management. Unless you use full power, you don't need to go to full-rich mixture for the recovery.
Keep the cowl flaps closed except if high temperatures suggest otherwise. Unless you've been lugging the airplane around in max-drag form on a hot summer day, chances are good that closed-flap cooling is sufficient. Finally, don't forget to manage your fuel supply. It's easy to get distracted by the maneuvering and let a tank run way down (or dry).
The following articles on this Web site provide additional information regarding this month's "Measure of Skill."
Safety and Education,
FAA Information and Services,
Learn to Fly,
Pilot Youth and Introductory
The NTSB has organized a safety seminar May 10 to focus on aerodynamic stalls and loss of control, a leading cause of general aviation fatalities.
According to the most recent Joseph T. Nall Report, in 2010 there were 43 accidents involving weather, and 28 of them were fatal. In fact, weather accidents are the most consistently fatal types of accidents.
AirSpace Minnesota has partnered with the Museum of Flight to create a new Aviation Learning Center.
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