Amateur-built OGG GLASAIR I N70GG accident near Reno, Nevada

Probable cause

The failure of an induction elbow following an engine backfire, which resulted in an in-flight fire and loss of engine power.

NTSB analysis

The airline transport pilot reported that the engine operated normally during the takeoff and initial climb to join up in race formation for the start of a closed course air race. During the initial climb, the pilot tested the nitrous system with no anomalies noted.

At the start of the race, the airplanes began a descent toward the first pylon. The pilot reported that she smoothly opened the throttle to full and turned the nitrous system on. The airplane flew normally as it accelerated, and the engine sounds were normal. As the airplane passed pylon No. 5, the engine suddenly stopped producing power. The pilot then pulled up and declared a mayday. She subsequently saw smoke begin to fill the cabin and flames on both sides of the engine cowling and in the cockpit under the instrument panel. The pilot subsequently landed on a runway, and emergency personnel extinguished the fire.

The airplane owner reported that the engine had backfired before the loss of power. The backfire caused an explosion in the induction system, which broke the induction elbow. The throttle body and nitrous injector dropped into the bottom of the cowling and sprayed flammable fluid into the engine compartment, which resulted in the fire and loss of power.

Text from the NTSB. Open the NTSB docket for WPR16LA184 for the full record.