Casualties unknown

2004-07-23: Air Tractor AT-502B (N5010E) — Douglas Thiel — Mendota, CA

Mendota, CA, US

On July 23, 2004, an Air Tractor AT-502B (registration N5010E) operated by Douglas Thiel was involved in an aviation accident near Mendota, CA. Investigators recorded the probable cause as: The pilot's inadequate preflight/pretakeoff procedure by not lowering the wing flaps, which resulted in an inadvertent stall as the pilot attempted to climb out of ground effect to clear a corn crop at the end of the runway. 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 an agricultural application flight, an airplane collided with high vegetation and terrain after the pilot failed to lower flaps and encountered issues extending them and releasing the cargo load.

Accident Overview

An agricultural application airplane was involved in an accident during the initial climb from a dirt airstrip. The aircraft collided with high vegetation and terrain after encountering difficulties with flap configuration and cargo release.

Sequence of Events

Prior to takeoff, the pilot did not lower the wing flaps to the 10-degree setting that had been used on previous takeoffs from the same airstrip. During the takeoff roll, the pilot realized the flaps were not set as accustomed and attempted to extend them. Despite these efforts, the flaps remained in the retracted position for reasons that could not be determined.

With approximately 20 feet of runway remaining, the pilot tried to release the load by deploying the cargo dump handle, but the attempt was unsuccessful. The airplane lifted off the runway but could not gain sufficient altitude to clear a nearby corn crop that was 5 to 6 feet tall.

Collision and Outcome

After impacting the corn, the airplane stalled, struck the ground, and cartwheeled three times before stopping in an inverted position. The specific damage to the aircraft was not detailed in the source.

Findings

The investigation noted the pilot's failure to set the flaps to the accustomed 10-degree position before takeoff, and the subsequent inability to extend them or release the cargo load during the takeoff roll.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20040813X01213. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.