A matter of inches

CEN11FA253

By David Jack Kenny

It’s sometimes called the “airshow pass,” and it can be pretty impressive when performed by a properly trained pilot in a suitable airplane: a dive for the threshold that levels off just a few feet above the pavement and then zooms the length of the runway, perhaps shredding a ribbon with the propeller before pulling up into a steep, aggressive climb. It looks easier than it is. Among the unusual piloting skills required are control of altitude within plus or minus inches and an acute awareness of angle of attack and the indications (if any) that precede an accelerated stall. Like most maneuvers requiring finesse, it’s best practiced at a safe altitude in an aircraft built to withstand the requisite G loads ... and close attention to weight and balance doesn’t hurt, either.

When pilots without that training succumb to the impulse to try it anyway, the results are often grim. The pull-up is where things usually go wrong. Most often the unexpected outcome is an abrupt accelerated stall at an altitude too low to allow recovery, as in the Beech Baron accident that provided a case study for the 2010 Joseph T. Nall Report. However, it’s also perfectly possible to pull the airplane apart first, especially if it’s been modified in ways that affect the loads imposed on the wings. And to reach that point, the pilot has to get the first part right—leveling off close enough to the runway to make it look good, but high enough to avoid contact with anything solid. Fixed gear provide a buffer, but doing it with retractable gear left retracted requires a fine eye for altitude and precise control.

A little before 2:30 p.m. on March 29, 2011, a Piper PA-46-350P took off from Bedford County, Pa. The 1,600-hour private pilot had flown two of his employees out from Monroe, Mich., that morning and they were now on their way home to Custer Airport. One hour and 20 minutes later the Malibu began its descent, and shortly before 4 p.m. the pilot made his 10-mile call on Custer’s common traffic advisory frequency.

A student pilot five miles west of the field in a Cessna 150 offered to let the faster airplane land first, and overflew the field about 1,000 feet above pattern altitude as the Malibu entered a left base for Runway 21. He watched it turn from base to final and cross the threshold, noticing nothing remarkable, and heard its pilot come back on the CTAF asking for a CFI the Malibu pilot had flown with in the past. He lost sight of the Malibu as he made a 270-degree right turn to join the downwind, but did see a fire burning southeast of the runway’s departure end. At the time, he did not connect the two.

Another employee of the FBO had responded to the radio call and gone to get the instructor, who was on the frequency within a few seconds. Two quick transmissions to the Piper had been met with no response. When they saw it cross the departure end of the runway no more than 50 feet agl with the gear retracted, they had concluded that the pilot was going around and turned away, only to hear the sound of an explosion behind them.

Three other witnesses saw the Malibu level off above the runway, gear and flaps retracted, flying conspicuously faster than normal approach speed. Descriptions of the engine noise ranged from “popping” and “not sounding right” to “running hard.” As it crossed the departure end of the runway the airplane began to climb, banked left, and then rolled level for just a moment before the left wing and nose dropped together. The impact triggered an explosion and fire that consumed much of the airframe. All three on board were killed.

Investigators found a series of 37 slash marks in the runway along with “material consistent with the aircraft propeller.” When they examined the wreckage, they found that “the propeller was attached to the hub but was separated at the propeller blade roots. The separation features were consistent with a propeller strike.”

The CFI took pains to point out that the pilot had no history of making low passes or indulging in any other kind of stunt, and no one reported hearing the pilot say, “Watch this!” Still, the NTSB attributed the accident to “The pilot's decision to attempt a low, high-speed pass over the runway,” in part because the wreckage showed no evidence of any abnormality prior to impact, and concluded that damage from the propeller strike made the airplane unflyable. They also found that it was 165 pounds over its maximum landing weight, with a center of gravity at least two and a quarter inches ahead of the forward limit … conditions that would have made it more difficult to level off and pull the nose up, whether the pilot was attempting an airshow pass or simply trying to go around after realizing he’d forgotten to extend the gear.