Accident Sequence
On September 23, 2016, at 1215 eastern daylight time, an Aero Vodochody L-39, registration N139AJ, sustained substantial damage when it impacted trees following a runway excursion while landing at Hampton Roads Executive Airport (PVG) in Norfolk, Virginia. The private pilot was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight conducted under 14 Code of Federal Regulations Part 91.
According to the pilot, while on final approach to runway 28, approximately 100 feet above ground level and 60 feet from the runway threshold, the flaps retracted without command. The pilot adjusted the airplane's pitch and advanced the throttle to compensate. The airplane touched down on the paved runway surface. The pilot applied the brakes, then activated the emergency brake. As the airplane veered toward the side of the runway, the pilot released the emergency brake and continued braking with the brake pedals. The pilot reported that normal braking was insufficient to prevent overrunning the runway. The airplane departed the end of runway 28, struck trees, and came to rest about 1,050 feet beyond the departure end. Runway 28 is 5,350 feet long.
An examination of the runway revealed skid marks beginning approximately 1,000 feet before the departure end and continuing to the area where the airplane stopped.
Aircraft Information
According to Federal Aviation Administration (FAA) records, the airplane was issued an experimental exhibition airworthiness certificate on December 12, 2007. It was powered by an Ivchenko AI-25TL engine. The pilot reported that the most recent condition inspection was performed on September 1, 2016, at an airframe total time of 3,016.9 hours. The airplane's emergency checklist indicated it was equipped with an emergency flap extension system; the pilot did not mention using that system during the accident sequence.
Post-Accident Examination
An examination of the flap system, overseen by an FAA inspector, found no disconnects or abnormalities in the flap mechanical actuation system aside from impact damage, which prevented functional testing. The flap actuator was intact, and no evidence of hydraulic leakage was noted. The emergency flap extension handle, located to the right of the pilot's seat, moved without anomaly.
A review of the airplane's flight manual indicated that, under the conditions at the time of the accident, the landing ground roll distance was approximately 2,000 feet. This calculation was based on idle engine power, full flaps, and retracted speedbrakes.