On August 3, 1994, a Piper PA-25 (registration N6568Z) operated by AG Air, Inc. was involved in an aviation accident near Spiritwood, ND. Investigators recorded the probable cause as: the failure of the fuselage tubing in the empennage. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 2 related events involving the same aircraft type or operator are linked below.
During landing on a private airstrip, an aircraft experienced shuddering and veered left. Pilot inputs failed to correct the turn, leading to a ground loop. Postaccident inspection revealed broken empennage tubing with internal rust.
Accident Details
During landing on a private airstrip, the airplane began to shudder and veer to the left. The pilot attempted to regain directional control by applying the right brake and increasing power. However, according to the pilot, these actions only accelerated the turn. The airplane subsequently ground looped and came to rest on the left side of the runway.
Postaccident Inspection
A postaccident investigation revealed structural damage in the empennage. Specifically, eight inches of the vertical fuselage tubing and the aft diagonal tubing near the tailwheel assembly were found broken in several locations. Rust was observed on the inside of the tubing wall near the breaks.