Casualties unknown

1998-06-16: Air Tractor AT-301 (N36576) — Risco, MO

Risco, MO, US

On June 16, 1998, an Air Tractor AT-301 (registration N36576) was involved in an aviation accident near Risco, MO. Investigators recorded the probable cause as: The pilot's delayed decision to abort the takeoff on a soft, thick sod airstrip while carrying a heavy chemical load, which resulted in the aircraft flipping over due to insufficient stopping distance and 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

An agricultural plane carrying chemical cargo failed to reach rotation speed on a soft, thick sod airstrip, leading the pilot to abort late and causing the aircraft to flip over.

What happened

The incident occurred during the takeoff phase of an agricultural flight operation. The pilot reported that the departure surface was characterized by very thick sod which had become somewhat soft due to recent conditions. The aircraft was loaded with approximately 2,000 pounds of chemical payload.

During the initial acceleration roll, the pilot observed that the airspeed was not increasing at the expected rate and that he would be unable to achieve the necessary takeoff speed before the end of the available runway. Recognizing the situation, the pilot delayed the decision to abort until it was too late to stop safely within the remaining distance. He subsequently applied the brakes as firmly as possible.

The heavy braking on the soft surface caused the aircraft to lose directional control and pitch forward violently. The airplane flipped over onto its back, resulting in significant structural damage. No injuries were reported among the occupants.

The investigation

A physical examination of the wreckage was conducted to determine if any mechanical failures contributed to the accident. Inspectors found no anomalies with the aircraft's systems or structure prior to the impact. The failure to accelerate adequately was attributed entirely to the combination of the heavy load and the poor surface conditions.

Findings

The primary factors leading to this accident were the soft, thick sod surface which increased rolling resistance and reduced acceleration performance. Additionally, the pilot's decision to delay the abort until it was impossible to stop safely played a critical role in the outcome.

Probable cause

The pilot's delayed decision to abort the takeoff on a soft, thick sod airstrip while carrying a heavy chemical load, which resulted in the aircraft flipping over due to insufficient stopping distance and loss of control.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X10248. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.