By David Jack Kenny
Legitimate aerobatics performed in appropriate locations by qualified pilots flying airplanes engineered for that use are a very safe activity. Accidents are extremely rare, typically numbering fewer than 10 per year and accounting for less than one percent of all those in fixed-wing aircraft. That said, those that do occur generally involve some combination of loss of control, in-flight structural failure, or high-speed impact—sometimes all three—so, it’s little wonder they tend to be severe. Nearly all are fatal.
Less-than-legitimate aerobatics—flights on which at least one of those conditions isn’t met—don’t fare as well in terms of minimizing overall risk, and when things do go wrong, they end every bit as badly.
The accident that killed two brothers, both longtime pilots and aviation enthusiasts, near Middletown, Ohio, on Sept. 20, 2014, satisfied at least one of these criteria. The airplane was an amateur-built Acro Sport II, a short-wing, tandem-seat biplane designed specifically for aerobatic performance. At its last condition inspection, completed the month before the crash, its logbooks showed almost 600 hours accumulated over the 20 years since its completion, presumably enough time for any flaws in workmanship to become apparent. The airplane had been acquired by a Middletown-based LLC two months earlier.
The older of the two pilots, age 49, was in the front cockpit. He held a private pilot certificate with instrument rating and had more than 1,700 hours of experience but just six hours in type. More than three-quarters of that had been acquired on the ferry flight home from North Carolina. His 40-year-old younger brother had logged more than 900 hours, but hadn’t obtained an instrument rating and had just two hours in the Acro Sport II. Their most recent medical applications indicated he outweighed his older brother by about 45 pounds. The NTSB concluded that at the time of the accident, the airplane was probably within its weight-and-balance limits, and both men wore parachutes as required by regulation.
Their level of aerobatic experience isn’t as well documented. The NTSB report doesn’t discuss their qualifications or lack thereof, and the archived excerpts from their logbooks aren’t much more helpful (aside from showing plenty of tailwheel experience). The older brother’s logbook noted an hour of “akro by myself.” The younger one’s included an entry for 1.5 hours of “loops, hammer, spins” with a CFI’s endorsement. Both of those flights were made in the Acro Sport II and suggest more than a beginner’s enthusiasm with an unfamiliar airplane.
Their choice of location, however, left something to be desired. A witness saw the Acro Sport fly past “at a lower altitude than she normally sees aircraft in the area,” then pitch up into a loop. At the top of the loop, the engine noise stopped and the airplane “entered a spiraling, spinning maneuver” that continued until it disappeared behind the trees. She heard the engine power up again just before the sound of impact. When the NTSB accident investigator asked her to illustrate the accident sequence with a model airplane, “the demonstration was consistent with an attempted loop with a spin out of the top of the maneuver.”
The biplane crashed into the garage of a home and caught fire. Slash marks in the siding proved that the propeller was turning, and the wreckage showed no evidence of damage that couldn’t be attributed to impact. The reason for the brief apparent power loss couldn’t be determined, but the probable cause of the accident was determined to be “the failure of the flying pilot to maintain airplane control after an aerodynamic stall/spin occurred during the aerobatic maneuver following a reported intermittent loss of engine power.” It was impossible to tell who was actually on the controls.
Instructors who specialize in that topic insist that given enough altitude, it’s possible to recover from nearly any in-flight upset. How much is enough depends on the characteristics of the aircraft and the pilot’s expertise. Lack of familiarity with an airplane is only one reason to set a higher floor before attempting any unusual maneuvers, but it’s a particularly good one. Likewise, the knowledge that things can indeed go wrong creates the obligation to at least try to shield bystanders from the consequences. Practicing aerobatics over a residential neighborhood at any altitude isn’t just a violation of 14 CFR 91.303, but of responsibility and common sense.