On November 19, 1995, a Cessna 210J (registration N3328S) was involved in an aviation accident near Bellefontaine, OH. Investigators recorded the probable cause as: THE PILOT UNKNOWNLY LEFT THE IGNITION SWITCH IN RIGHT MAGNETO-ONLY POSITION, WHILE MOVING THE PROPELLER BY HAND, WHICH ALLOWED AN INADVERTENT START OF THE ENGINE. THE WEAK BATTERY WAS A RELATED FACTOR. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot attempting to hand-prop an engine after multiple failed starts caused the aircraft to lurch forward, striking a parked airplane and a hangar. The ignition key was found in the right magneto-only position.
Incident Overview
The pilot of a single-engine airplane attempted to start the engine multiple times without success. After four or five failed attempts, he attributed the problem to a weak battery resulting from infrequent use. He then turned off the ignition and manually rotated the propeller by hand, intending to clear the engine. To his surprise, the engine started during this hand-propping procedure. The airplane immediately moved forward across the ramp and collided with a parked airplane and a hangar.
Postaccident Examination
Following the incident, an examination of the airplane revealed that the ignition key remained in the ignition switch. The ignition was set to the right magneto-only position. No anomalies or malfunctions were found in any aircraft systems. The engine started unexpectedly because the ignition was still active, despite the pilot's belief that it was off.
Contributing Circumstances
The pilot had reported that the battery was weak due to infrequent use, which led to the initial starting difficulties. His decision to hand-prop the propeller without verifying that the ignition was completely off resulted in the unintended engine start and subsequent ground collision.