Propeller Blade Fragment Loss Leads to Forced Landing and Nose Over (N7498)

Q: What aircraft was involved and where did it happen?

The accident on 1989-09-08 involved a Grumman G-164A, registration N7498, operated by Terry Flying Service, at Franklin, LA.

On September 8, 1989, a Grumman G-164A (registration N7498) operated by Terry Flying Service was involved in an aviation accident near Franklin, LA. Investigators recorded the probable cause as: A pre-existing crack on the leading edge of the propeller blade led to the blade fracture. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

An agricultural aircraft made a forced landing after severe vibrations caused by a propeller blade losing 13 inches of its length. The aircraft nosed over during braking on soft terrain. Investigation revealed a pre-existing crack on the blade's leading edge.

Incident Overview

An agricultural pilot had just completed spraying a load of chemicals and was turning to assess the next field for spraying when the airplane began to vibrate violently. The pilot responded by reducing power and maneuvering to align with a turnrow for an emergency landing.

Forced Landing

After touchdown, the aircraft rolled approximately 300 yards over soft terrain. As the pilot applied brakes to avoid a ditch, the airplane nosed over, resulting in damage.

Investigation Findings

Examination of the aircraft revealed that 13 inches of one propeller blade was missing. A detailed analysis of the fracture surface indicated the presence of a pre-existing crack on the leading edge of the blade, which led to the blade failure and subsequent vibrations.

Probable Cause

The investigation determined the probable cause to be a pre-existing crack on the leading edge of the propeller blade, which resulted in blade fracture and loss of blade segment.

1989-09-08: Grumman G-164A (N7498) — Terry Flying Service — Franklin, LA