What happened
On August 20, 2021, a North American SNJ-2, registration N52900, was destroyed during a practice flight for the Great Pocono Raceway Airshow in Wilkes-Barre, Pennsylvania. The aircraft was operating as part of the Geico Skytypers Air Show Team, a six-plane formation.
The flight began with a formation takeoff. The pilot of N52900 was leading the second element of the formation. Shortly after takeoff, at approximately 100 feet above the ground, the aircraft began to decelerate. The pilot's wingman observed the landing gear retracting and heard the pilot transmit an emergency message over the radio.
Following the loss of power, the aircraft entered a left turn. As the bank angle increased past 20 degrees, the aircraft continued to slow and descend. The aircraft's smoke system activated just before the plane impacted the ground, resulting in a post-impact fire. The pilot sustained 1 fatal injury.
The investigation
Investigators examined the wreckage, which was severely fire-damaged. The engine had separated from its mounts, and the empennage and left wing panel had also separated from the airframe. Examination of the propeller indicated signatures consistent with low power at the time of impact. A witness video also captured engine back-firing noises prior to the descent.
Maintenance records showed that on the day before the accident, the pilot had reported the engine was "banging" during a magneto check. The Director of Maintenance had identified a compressed P-lead spring on the left magneto and replaced it, after which subsequent engine runs showed no anomalies.
Post-accident testing of the ignition system revealed that the right magneto was performing poorly, rotating too easily due to weak magnetism and failing to fire on all points until reaching 180 rpm. While the left magneto was too damaged by impact for a full evaluation, investigators noted that the extent of the fire damage prevented a complete examination of the ignition system wiring.
Findings
- The aircraft experienced a partial loss of engine power for undetermined reasons.
- During the attempt to break out of the formation and maneuver for a forced landing, the pilot entered a steep left turn.
- This maneuver increased the load factor, which significantly raised the aircraft's stall speed.
- The pilot exceeded the aircraft's critical angle of attack, resulting in an aerodynamic stall and subsequent loss of control.