On April 21, 1994, a Schweizer 269C (registration N3623Y) was involved in an aviation accident near Fargo, ND. Investigators recorded the probable cause as: The pilot inadvertently raised the collective prematurely and allowed the main rotor speed to decay. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a check ride for a helicopter flight instructor certificate, the pilot inadvertently raised the collective prematurely during an autorotation, causing main rotor speed decay and a hard landing with substantial damage.
Accident Summary
During a check ride for a helicopter flight instructor certificate, the pilot was demonstrating autorotations to touchdown to an FAA inspector. As the helicopter turned from base to final, the pilot inadvertently raised the collective prematurely, which allowed the main rotor speed to decay. The helicopter subsequently landed hard and sustained substantial damage.
Pilot and Inspector Actions
The pilot reported the premature collective input and subsequent rotor speed decay. The FAA inspector aboard was aware that the helicopter was going to land short of the intended touchdown site. The inspector noted that he normally rests his hand on the collective during practice autorotations but did not do so on this occasion.
Damage
The helicopter received substantial damage as a result of the hard landing.
Probable cause
The pilot inadvertently raised the collective prematurely and allowed the main rotor speed to decay.