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Aftermath: His Last Selfie

An amateur test pilot records an unrecoverable spin.

The ready availability of small, light video cameras has produced an outburst of visual autobiography. Hardly anyone seems to be able to resist the temptation to strap a camera to his head and do something that he, or someone else, may later find exciting or impressive. Skiers, skateboarders and sky divers are particularly enamored of this form of self-documentation, but pilots are not immune to its charm. It is now possible to view on the Internet several crashes, and at least two midair collisions, as seen from the point of view of the participants. As far as I know, all of the subjective accident videos to be found on the Internet depict nonfatal accidents. The National Transportation Safety Board keeps the others to itself. At least I hope it does.

In August 2013 an Idaho pilot set out to try some spins in the KR-2 he had acquired from its amateur builder a year earlier. He mounted a camcorder on the canopy frame behind and to the right of his seat, looking over his shoulder. He took off in the early evening and climbed to 3,600 feet above the ground. There he pulled the throttle to idle, raised the nose into a stall and then, with the stick fully back, pushed the left rudder pedal to the floor.

The airplane sliced to the left and pitched down, and within a couple of seconds had begun to spin. After the first turn, the pilot released the left rudder pedal, pressed the right and moved the stick forward.

The spin continued.

It stabilized about 50 degrees nose down with rapid rotation — less than two seconds per turn. The indicated airspeed dropped to zero and the vertical speed pegged at 2,000 feet per minute. The oil pressure went away and after about 10 seconds the engine stopped, probably because of fuel starvation. The airplane had now lost 1,100 feet. The pilot tried every combination of right and left stick, right and left rudder, and fore and aft stick, but nothing worked. After about 45 seconds and 25 turns, the airplane crashed into a densely wooded area, its fall somewhat cushioned by trees.

The video camera, undamaged, continued to run for more than three hours. It recorded ambient sounds, including the ringing of a cellphone, the distant barking of a dog and the arrival, after nightfall, of would-be rescuers. For more than two hours after the crash the strained breathing of the pilot could be heard, but he died before help reached him.

The Rand Robinson KR-2, which made its debut at Oshkosh in 1974, has been an extremely popular design. Thousands of sets of plans have been sold and, though it was axiomatic in the era of homebuilts bought as plans rather than kits that the majority would never be completed, in the past 40 years more than 1,000 were actually built, and 875 remain in the FAA registry (which does not include ones registered abroad). The designer, Ken Rand, did not live to taste all the fruits of his labor. Returning home in the KR-2 prototype from Sun ‘n Fun in January 1979, he crashed, after flying nonstop from Texas, in the San Gabriel Mountains just north of Los Angeles.

The original specifications of the KR-2 included an empty weight of 420 pounds, a figure few builders are able to achieve, and a converted Volkswagen engine of the old flat-opposed air-cooled variety. The very low empty weight implied the omission of any electrical system whatever. The design gross weight was 800 pounds. It’s safe to say, even without having surveyed the entire fleet with a set of electronic scales, that most KR-2s were, and are, overweight.

As designed, the KR-2 is very compact. Some builders have stretched fuselages and some have made them wider than the plans specify; the boxlike wooden-­tub construction makes such modifications easy. Some have retractable gear, some fixed, some tailwheel, some tricycle. Some have more powerful engines and extra fuel. There is, in fact, just about no such thing as an absolutely “stock” KR-2.

Intended as a fast, economical cross-country cruiser, the KR-2 does not appear to have been designed with spin recovery in mind. The tail moment arm is very short, the tail surfaces are small, and the square-bottomed fuselage is bulky relative to them. The vertical and horizontal surfaces are not staggered in such a way as to keep the rudder from being “blanketed” or “shadowed” by the horizontal tail in a post-stall attitude. On the other hand, a portion of the rudder does extend below the elevator, where it cannot be blanketed, and the wing loading is low, suggesting that the dominant factor in the spin would be aerodynamics rather than momentum. According to the current distributor of KR-2 plans and parts, he had spun “stock” KR-2s and found them “similar to other low-wing light airplanes.”

If aerodynamic forces were the only ones involved, the ability to recover from a spin would depend mainly on the authority of the rudder. But the mass of the airplane and its distribution also have roles in determining both the attitude in which the plane spins and the effort needed to arrest its rotation. CG position is also important; the farther aft the CG, the more difficult the recovery. Small aerodynamic modifications, like wing root fairings and strakes ahead of the horizontal stabilizer, can affect spinning behavior. How an airplane spins, what kinds of spins it is capable of and how readily it recovers are questions that only extensive flight testing can fully answer. This KR-2 had not been spin tested before; its operating limitations mentioned, among aerobatic maneuvers, only wing-overs, loops and rolls.

The accident airplane was equipped with a Continental A-75 engine, which is heavier than the Volkswagen. If a slightly heavier engine moved the CG forward it might not have an adverse effect upon spinning characteristics, but if ballast were added at the tail to restore the normal CG location the flywheel effect of the increased mass at a distance from the center could make the airplane more reluctant to stop spinning. The NTSB’s report on the accident does not discuss the presence or absence of ballast, nor whatever documentation of the airplane’s weight and balance existed, if any. There is no information about the rigging, the control surface deflection limits, and so on. The NTSB does not mention a parachute, and the pilot was presumably not wearing one. Nor is there any information about his previous training or experience in spinning. His logbook was not found. His most recent medical application, filed 18 months before the accident, reported 305 hours total time, with none in the previous six months.

A spin is an interesting and exciting maneuver, and it is easy to understand why some pilots want to experience it. Very few pilots, however, are aware of the subtleties of spin aerodynamics. Most likely this pilot heard from other owners that the KR recovers conventionally. But homebuilt airplanes, especially those not built from largely prefabricated kits, are each unique. That is why, if your name is Bunbury and you build an RV-7, the FAA registers your airplane as a Bunbury, not a Van’s.

When spin tests are conducted in production airplanes — normal- and utility-category airplanes are required to demonstrate recovery from a one-turn spin, but not from a “developed” spin — a chute is usually attached to the tail to yank it upward in case the flight controls prove ineffective. Homebuilders generally can’t afford spin chutes, but when spinning a previously untested airplane they should at least provide themselves with a parachute, contemplate how they would get out of the airplane while panicky and under G forces pulling and pushing in unexpected directions, and begin their spins at a sufficiently high altitude — at least 8,000 feet agl — to permit ample time for recovery and, failing that, for escape. Spins are fun, but they are not child’s play.

This article is based on the NTSB’s report of the accident and is intended to bring the issues raised to our readers’ attention. It is not intended to judge or to reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory.

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