The Spin Debate | Flight Today | Air & Space Magazine
Current Issue
October 2014 magazine cover
Subscribe

Save 47% off the cover price!

The Spin Debate

If spins can kill, why aren't pilots trained to handle them?

Air & Space Magazine | Subscribe

IMAGINE YOU'RE FLYING A LEFT-HAND APPROACH to the local airport. you're on the base leg, perpendicular to the runway, with its near end at your left front quarter as you bank into the left turn for the final leg. Halfway into the turn, you realize that a cross-wind is pushing you beyond the centerline, so you bank a little more. When it’s clear that won’t be enough to realign you properly with the runway, you kick in some extra left rudder to move the tail around, but that increases the bank angle. Your instructor has beaten into your head that you never make steep turns close to the ground, so you instinctively do what you always do to bring the left wing up: You turn the wheel to the right. To your surprise, the left wing dips further, so you turn the wheel still further to the right.

From This Story

You have just made a classic mistake.

Suddenly the right wing flips up over the top, and the nose swings toward the ground as the airplane starts spinning. Since your altitude turning final is only 300 to 400 feet above ground level (AGL), do you have room to recover? I never asked myself that question when I was training for my private pilot’s license many years ago. My instructor, who believed in spin training even though it was not mandated by the Federal Aviation Administration, took me to a generous 4,000 feet AGL and demonstrated how to force the airplane into a spin and how to recover. Then he had me do two one-turn spins to the left and two more to the right. It was exhilarating! I was good at it! Patting myself on the back, I declared myself proficient. Unexpected spins at low altitude were a dimly recognized and easily dismissed possibility.

I’ve learned a lot since then.

I did a search of the National Transportation Safety Board’s records and found that since January 2001, there have been more than 80 stall/spin accidents in general aviation in the United States. And last year, Pat Veillette, an instructor in the personnel training department of a major air carrier, did a formal study of the NTSB’s records and found that between 1994 and 2000, there were 394 spin-related accidents in this country. Fatal accidents numbered 324, including one on May 25, 1997, when a Cessna 205 crashed in Homestead, Florida, during a skydiving outing, killing all but one of the seven persons on board. The NTSB accident report reads in part: “A passenger-parachutist stated she had exited the cabin and was on the jump platform preparing to jump from about 3,500 feet when the left wing and nose dropped and the aircraft entered a spin to the left. After an unknown number of revolutions she jumped from the aircraft and deployed her chute. She observed the aircraft continue in a spin until ground impact.”

The NTSB determined the probable cause of the accident: “The pilot-in-command’s failure to maintain airspeed as he slowed for a parachutist to jump from the aircraft, and his failure to apply spin recovery emergency procedures prior to ground impact. Contributing to the accident was the pilot-in-command’s lack of training in spin recovery emergency procedures in an aircraft.”

Accidents like this one further a debate that has divided the aviation community since 1949, when the Federal Aviation Administration eliminated from the syllabus for a private pilot’s license the requirement for spin training. John Wensel, manager of the FAA’s Certification Branch, General Aviation and Commercial Division, Flight Standards Services, recounts his agency’s reasoning: “We saw that 48 percent of the fatal accidents from that era involved stall/spin, and of those the majority were training-related. We were killing people in trying to eliminate the very thing that was happening to them.” A number of general aviation pilots, however, think that the requirement for spin training should be reinstated. Their reasoning: Everything about flying takes practice. How can a pilot possibly recover from something as disorienting as a spin if the first encounter is an unexpected one?

Inadvertent spins are dangerous because they are disorienting. Imagine you are in a car suspended by a rope around its rear bumper. The other end of the rope is attached to a flagpole jutting out from a very tall building, so you sit staring straight at the concrete far below. Someone starts the car moving in a circle while simultaneously turning on its own axis as the car’s front end starts pitching from side to side. Now someone cuts the rope. That’s what it feels like to be in a spin.

In the earliest days of flying, a spin was certain death, but beginning in 1912, a smattering of pilots somehow extricated themselves from spins. Mathematician F.A. Lindemann is most often named as the first to have developed an aerodynamic theory of spins and a procedure for recovery. He learned how to fly and tested both the theory and the procedure himself in 1916. The method of spin recovery now described in modern flight manuals, known as PARE, is no more than a mild refinement of Lindemann’s.

PARE is an acronym developed by flight instructor Rich Stowell to help pilots remember the sequence of control inputs necessary for a spin recovery: Power (close the throttle), Ailerons (neutralize), Rudder (full deflection in direction opposite the spin), Elevator (first, stick forward to un-stall the wing). An alternative is the Muller-Beggs method, which is similar to PARE with one dramatic exception: for PARE’s “neutralize ailerons” phase of recovery it substitutes “take your hands off the stick.” Neither of these methods is guaranteed to work for every airplane in every situation.

Comment on this Story

comments powered by Disqus