Bell 222 N222ML accident near Montgomery, New York

Probable cause

A partial loss of engine power, as reported by the pilot, during takeoff for reasons that could not be determined based on available information.

NTSB analysis

The twin-engine helicopter was about 500 ft into the initial climb after takeoff from the pilot’s private property when he noticed a “split” in the #1 and #2 engine rpm needles, with the #1 engine rpm indicating below normal operating rpm, and the #2 engine rpm indicating above normal operating rpm. The pilot believed that this was believed that this was indicative of a loss of power on the #1 engine and returned to the property for a run-on landing. The helicopter touched down, encountered uneven ground, and rolled onto its left side, which resulted in substantial damage to the airframe.

Postaccident examination of the airframe found both of the throttles near the idle position, and no evidence of any preimpact mechanical malfunctions or failures of any airframe components. Both engines and their respective power turbine governors were examined and successfully test run after the accident. During the examinations, the #2 engine’s P3 Ng speed sensor connector was found disconnected. According to the engine manufacturer, if the disconnection had occurred inflight, the cockpit indication of the engine speed for the #2 engine would have been zero. Given this information, and the pilot’s description that the #2 engine rpm was abnormally high, it is likely that the disconnection of the connector occurred as a result of the accident sequence and not during the flight. Based on these findings, the reason for the difference between the indications of the two engines that the pilot observed during the takeoff could not be determined.

Text from the NTSB. Open the NTSB docket for ERA19LA145 for the full record.