On December 18, 1992, a Schweizer 269C (registration N6129Q) operated by Schweizer Aircraft Corp was involved in an aviation accident near Elmira, NY. Investigators recorded the probable cause as: AN UNSTABLE TOUCHDOWN WHICH RESULTED IN A ROLLOVER, INADEQUATE SUPERVISION BY THE PIC, AND FAILURE OF THE PIC TO TAKE CONTROL OF THE HELICOPTER IN A TIMELY MANNER. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a new aircraft acceptance flight test, a helicopter practicing a touchdown autorotation touched down with a right drift and lower right skid, rolling onto its side. Both pilots were on the controls, and no transfer of control procedures had been established.
Accident
A helicopter was performing a new aircraft acceptance flight test with two pilots on board when it sustained a rollover accident. The aircraft had been practicing a touchdown autorotation. During the landing, the helicopter touched down with a right drift and with the right skid lower than the left. After touchdown, it rolled to the right and came to rest on its side.
Flight Details
The left seat pilot represented the purchaser of the aircraft, and the right seat pilot was a company pilot designated as pilot in command. Both pilots were on the controls at the time of touchdown. No transfer of control procedures had been established before takeoff. Additionally, the left seat pilot had gone 13 months without performing touchdown autorotations in this type of helicopter.
Operational Context
The flight was conducted as a test for acceptance of the new aircraft. The pilots were actively engaged in practicing an autorotation maneuver intended to simulate a power-off landing. The lack of established control transfer procedures meant that both pilots were simultaneously handling the controls during the critical touchdown phase.