On August 2, 1989, a Grumman G-164A (registration N952X) was involved in an aviation accident near Sullivan, IN. Investigators recorded the probable cause as: The pilot's decision to abort the takeoff after experiencing abnormal engine performance due to a leaking turbocharger oil seal, which resulted in a loss of control and nose-over. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
The pilot aborted takeoff after the aircraft felt mushy during initial climb. Loss of control caused a nose-over, traced to an oil leak soaking spark plugs.
What happened
During the initial climb phase following takeoff, the pilot reported that the airplane exhibited abnormal handling characteristics, describing the controls as feeling "mushy." In response to the perceived loss of power or control, the pilot lowered the nose and applied full throttle. The pilot then decided to abort the takeoff. During this aborted maneuver, control of the aircraft was lost, resulting in the airplane nosing over.
The investigation
A post-accident inspection of the aircraft revealed a leaking oil seal on the turbocharger. This leak allowed oil to enter the intake manifold and soak the spark plugs, likely causing engine roughness or power loss that contributed to the mishandling during the critical phase of flight.
Probable cause
The pilot's decision to abort the takeoff after experiencing abnormal engine performance due to a leaking turbocharger oil seal, which resulted in a loss of control and nose-over.