EC 135 P2+ N238AM accident near Pottsville, Pennsylvania

Probable cause

The pilot’s failure to ensure that both engine switches were in the FLIGHT position for takeoff.

NTSB analysis

After taking off on a helicopter emergency medical service mission, the twin-engine helicopter climbed approximately 75 feet. The pilot lowered the nose, but the helicopter would not climb or accelerate normally. The pilot saw 125 percent on one of his gauges, but was not sure which gauge it was as he was looking outside. A "gong" sounded, similar to what the pilot had heard when doing "max takeoffs," but he did not hear an engine-out horn or see any warning lights. The pilot also noticed that one torque indication was declining to "near zero" percent, and the helicopter began to yaw. The pilot was able to correct the yawing moment with anti-torque inputs, and remembered lowering the collective and "pulling pitch" before the helicopter impacted the ground in a level attitude. The No. 1 engine was running as the pilot exited the helicopter, but the No. 2 engine was not. Examinations at the accident site revealed that the helicopter, after lifting off from the heliport, flew out of ground effect over down-sloping terrain, settled, then struck a parked semi-trailer about 80 feet below the heliport. No preimpact mechanical anomalies of the helicopter, engines, or engine switches were found. As part of the pre-takeoff confirmation check, the pilot was required to ensure that both main engine switches were in the FLIGHT position; however, onboard recorded data revealed that the No. 2 main engine switch was in the IDLE position during the takeoff.

Text from the NTSB. Open the NTSB docket for NYC08FA198 for the full record.