On November 22, 1985, an Enstrom F-28F (registration N86229) operated by Alfred M. Gore was involved in an aviation accident near Miami, FL. Investigators recorded the probable cause as: The pilot's inability to maintain engine RPM, which led to an emergency landing where the skids dug into soft dirt and caused the helicopter to roll over. The cause of the RPM loss could not be determined due to the lack of inspection of the rotor system. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter pilot attempted an emergency landing in a plowed field after experiencing engine RPM loss. The skids dug into soft dirt, causing the aircraft to roll over. No pre-impact mechanical failure was found.
What happened
The pilot reported that he noticed a decrease in engine revolutions per minute (RPM). In response, he opened the throttle and lowered the collective pitch to restore power. These corrective actions did not produce the desired RPM increase. Consequently, the pilot attempted to land the helicopter in a nearby plowed field. During the landing attempt, the skids dug into the soft dirt, causing the helicopter to roll over.
The investigation
An examination of the engine disclosed no evidence of a pre-impact malfunction or failure. However, the rotor system was not checked during the inspection. No determination was made as to the reason for the loss of RPM.
Probable cause
The pilot's inability to maintain engine RPM, which led to an emergency landing where the skids dug into soft dirt and caused the helicopter to roll over. The cause of the RPM loss could not be determined due to the lack of inspection of the rotor system.