On August 5, 1988, a Bell 47J (registration N2838B) operated by Chester Ruminer was involved in an aviation accident near Dowagiac, MI. Investigators recorded the probable cause as: FAILURE TO MAINTIAN ADEQUATE ROTOR RPM BY THE UNQUALIFIED PILOT. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
On his first familiarization flight in a helicopter model, a private pilot experienced engine power loss after takeoff. The helicopter settled into trees, causing damage. Investigation revealed a blocked air filter from rat nest material and auto fuel in the system.
Accident Details
A private pilot with an airplane single-engine land rating was conducting his first self-familiarization flight in this make and model of helicopter. After takeoff, the pilot flew approximately half a mile and initiated a turn. During this maneuver, the engine began losing power. The helicopter subsequently descended and settled into trees, sustaining damage. Evidence indicated that the engine was still producing power when the main rotor blades contacted small trees during the landing.
Investigation Findings
An investigation into the accident revealed that the last annual inspection of the helicopter was dated August 22, 1985. The air filter was found to contain rat nest material in sufficient quantity to almost completely block the flow of air. Additionally, auto fuel was detected in the fuel tanks and carburetor.
Pilot Information
The pilot's last medical certificate was issued on January 2, 1986.