Teaching The Stall/Spin Safely
The Spin Training Story-And Why It's Still ImportantDid you know that about 9 percent of general aviation accidents are stall/spin accidents? Or that 29 percent of these accidents are fatal? Stall/spin accidents kill almost 13 percent of all people lost in GA aircraft.
So it is important for all pilots to sharpen their knowledge and skills on what causes accidental stalls and spins, with emphasis on how to avoid the situations that lead to these accidents. Both stalls and spins can be fun and need not be dangerous except when done inadvertently or too close to the ground, without sufficient altitude to recover, or in an airplane not approved for intentional spins.
All a pilot needs to know are stall recognition and recovery procedures. A pilot needs to know when a stall is approaching, and then what to do to avoid the stall. There are ways that instructors can sharpen their teaching techniques to better achieve these pilot objectives.
Prior to 1949 spins were a required flight-test item. Each applicant was had to make a two-turn spin to the left and a two-turn spin to the right, with a precision recovery to within 10 degrees of a heading. A private pilot applicant typically got initial spin training at about the sixth hour. Typically at about 13 hours the student was permitted to practice solo spins.
Then, in 1949, the Civil Aeronautics Administration, which preceded the Federal Aviation Administration, adopted CAR Amendment 20-3 that eliminated spin testing except for flight instructor applicants. CFI spin testing has been required ever since. One concept behind this change was that future design would produce spin-proof airplanes, thus making the spin requirements obsolete - but that never really happened. Certification regulations have discouraged the development of spin-proof airplanes.
What did happen was a reduction in spin accidents. In the 1945 to 1948 period, just before the change was made, 48 percent of all fatal accidents were stall/spin-related.
From 1967 to 1969, when spins were no longer required except for CFI applicants, the number of stall/spin fatalities had decreased to 22 percent. NTSB data for 1972 to 1979 show that the stall/spin was a primary factor in only 12 percent of all fatal accidents. Now that figure is about 9 percent, but fatalities are high.
The debate concerning the value of spin training and testing continues. Studies of accidental spins are inconclusive. One study some years ago concluded that a high number of these accidents occurred with a flight instructor aboard, one study showing as many as 58 percent.
No useful information is consistent with regard to how many accidents occur in terms of age or hours of flight experience. What is evident is that many stall/spin accidents involve aerobatic flight at low level. A somewhat common spin scenario is a cross-controlled stall while turning from base leg to final approach. Many occur in the traffic pattern after takeoff and before landing. These accidents at low level are almost always fatal.
For student pilots, the first stalls should be no more than partial stalls, a gentle slowing of the airplane followed by a lowering of the nose - a reduction of the angle of attack - to regain cruise speed. Avoid thrilling the student with sudden and violent actions. For some beginning pilots, the mere mention of a stall or spin creates anxiety that is a deterrent to learning, which should be avoided. The objective of the gradual approach is to give the student time and an opportunity to learn proper rudder action.
Knowing how and when to use the rudder is the key to good stall and spin control, and is a key to coordination.
The first spin with a student should probably be a half-turn spin, done as simply as possible. Next, a one-turn spin. Any need to go beyond that? Many instructors think that this is adequate, for in the end you are teaching stall and spin prevention. That means recognizing the approach of a stall and then promptly taking recovery action. Remember, if the airplane doesn't stall, it won't spin. The best spin prevention is stall recognition and recovery. Reduce the angle of attack. No stall, no spin.
Choose carefully the airplane that you will spin. Not all of the airplanes we use in training today are approved for intentional spins. General aviation airplanes are tested with a one-turn spin and controls relaxed. Unassisted recovery must come within one turn. If not, spins are not authorized. An aerobatic airplane is spun six turns and must recover within one and one-half turns. If it doesn't, spins are not authorized in the aircraft.
Under no circumstances should you spin a twin. Spins are not authorized for twins. Nor should anyone spin a four-seat airplane with anybody in the back seat or with an aft load. The danger is a flat spin, which can be unrecoverable.
Parachutes are required for aerobatic maneuvers, but FAR 91.307 excuses the parachute rule for flight tests for certificates or ratings and allows authorized instructors to give spin training to any level of pilot certification without parachutes. For all others, parachutes are required.
Remember, as an instructor you play a large role in making certain that your students never become stall/spin statistics.
Ken Medley is an 11,000-hour commercial pilot, CFI, and former DPE. He was recently inducted into both the Illinois and NAFI aviation halls of fame.
By Ken Medley