Casualties unknown

1984-08-30: Boeing STEARMAN E75 (N5183N) — Kalispell, MT

Kalispell, MT, US

On August 30, 1984, a Boeing STEARMAN E75 (registration N5183N) was involved in an aviation accident near Kalispell, MT. Investigators recorded the probable cause as: The pilot's failure to maintain adequate clearance from a bird during an aerial application maneuver, which resulted in a collision and subsequent loss of control. 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 1781061362Data APIEditorial standards

During a routine aerial application maneuver, the aircraft struck a bird at low altitude, causing canopy damage and loss of control before flipping over on impact with the ground.

What happened

The pilot was conducting a standard aerial application flight when the incident occurred. While completing a turn to final approach for crop dusting, the aircraft was approximately 15 feet above ground level and traveling at 65 miles per hour. At this altitude, the aircraft collided with a bird, which was presumed to be a red-tailed hawk.

The force of the impact shattered the plexiglass canopy and caused a momentary distraction for the pilot. In the split second that followed, the aircraft descended rapidly and made contact with soft dirt terrain. The nose of the plane dug into the ground, causing the aircraft to flip over completely.

The investigation

Investigators examined the wreckage and noted the damage to the canopy structure consistent with a high-energy impact from an external object. The condition of the propeller and engine was reviewed to rule out mechanical failure prior to the collision. The terrain at the site of impact consisted of soft dirt, which contributed to the nose digging in during the subsequent ground contact.

Findings

The primary factor in this accident was the bird strike at low altitude during a critical phase of flight. The resulting damage to the canopy and the pilot's momentary distraction led to a loss of control. The aerial application maneuver placed the aircraft in proximity to wildlife activity, increasing the risk of collision.

The pilot retained control until the initial impact, but the combination of structural damage and terrain interaction resulted in the rollover. No further mechanical anomalies were identified that would have contributed to the sequence of events.

Probable cause

The pilot's failure to maintain adequate clearance from a bird during an aerial application maneuver, which resulted in a collision and subsequent loss of control.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X40668. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.