What happened
While performing a swath run, the Piper PA-25 experienced a structural failure when the right wing buckled. This caused the aircraft to roll into a descent, resulting in a crash.
The investigation
A post-accident examination of the aircraft identified that the forward spar fuselage attachment assembly for the right wing had failed. The failure was attributed to fatigue at the clevis ears.
Findings
The investigation noted a similar failure involving a Piper PA-25 occurred on September 21, 1991. Following that event, on May 13, 1992, the NTSB issued an urgent recommendation to the FAA requesting an Airworthiness Directive (AD) for all Piper PA-25 aircraft. This recommendation included immediate inspections for corrosion and cracking of the clevis ears, required repairs if such issues were found, and the establishment of periodic inspection requirements to detect cracks before they reached a critical state. Although the FAA agreed with the intent of this recommendation on July 16, 1992, no formal inspection procedure was in effect at the time of the accident.