Casualties unknown

Left Wing Separation Due to Corrosion from Chemical Spraying (N7509Z)

Brewton, AL, US

On September 21, 1991, a Piper PA-25-235 (registration N7509Z) operated by Wallace Flying Service was involved in an aviation accident near Brewton, AL. Investigators recorded the probable cause as: Failure of a wing front spar fitting clevis ear due to corrosion from chemical spraying, and absence of an inspection procedure for that area. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-07-04Data APIEditorial standards

The left wing separated from the airframe when a wing front spar fitting clevis ear failed. Corrosion between welded sections, attributed to chemical spraying over time, caused the failure. No inspection procedure existed for that area.

Separation

The left wing separated from the airframe when one of the two wing front spar fitting clevis ears failed.

Examination Findings

Examination of the failed component uncovered corrosion between the sections making up the welded clevis ear. The accumulation of corrosion was attributed to chemical sprayed from the airplane over a long period of time. Additionally, no inspection procedure was specified for this area of the wing fitting.

NTSB Recommendation

Subsequently, the NTSB issued a recommendation requesting an inspection procedure to prevent the formation of corrosion between the layers of clevis material.

Probable cause

Failure of a wing front spar fitting clevis ear due to corrosion from chemical spraying, and absence of an inspection procedure for that area.

Frequently asked questions

What happened in the 21 Sept 1991 Piper PA-25-235 accident near Brewton, AL?

The left wing separated from the airframe when a wing front spar fitting clevis ear failed. Corrosion between welded sections, attributed to chemical spraying over time, caused the failure. No inspection procedure existed for that area.

What aircraft was involved and where did it happen?

The accident on 21 Sept 1991 involved a Piper PA-25-235, registration N7509Z, operated by Wallace Flying Service, at Brewton, AL.

What was the probable cause of the accident?

Failure of a wing front spar fitting clevis ear due to corrosion from chemical spraying, and absence of an inspection procedure for that area.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X18028. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.