Pilot dies after extending full flaps during pesticide application takeoff

Casualties unknown • Lenox, IA, US

A pilot died from burns after colliding with a fence and the ground during takeoff in an agricultural aircraft loaded with pesticide. The accident occurred on a grass runway with limited mowed area, exacerbated by high density altitude and nearby thunderstorm activity.

What happened

The aircraft was engaged in agricultural operations when it collided with a fence during the initial phase of takeoff. The plane was carrying a full load of chemical pesticide at the time of the incident. Following the impact with the fence, the aircraft struck the ground, which ignited a fire.

The pilot sustained serious burn injuries and later died from those wounds. While being transported to the hospital, the pilot provided an account of the events leading up to the crash. He stated that he had intended to dump the pesticide load to lighten the aircraft for takeoff. However, he mistakenly grabbed the flap control handle instead. This error caused the flaps to extend fully, drastically increasing drag and preventing the aircraft from gaining sufficient lift.

The runway in use on the day of the accident was a grass strip with turf approximately one to two feet deep across most of its length. Only a 300-foot section in the middle of the field had been mowed; this area was typically used by local flyers operating radio-controlled model aircraft. The density altitude at the airport was calculated to be 2,200 feet, a condition that reduces engine performance and lift generation. Weather reports indicated thunderstorm activity in the vicinity, located north of the airport and approximately two miles south of the runway.

This incident marked the pilot's third accident involving agricultural operations. A previous incident had involved an aborted takeoff and a crash off the end of a runway. The pilot's flight time was not reported, and his logbooks could not be located for review.

Findings

The primary factor in this accident was the pilot's error in extending full flaps while attempting to dump the pesticide load. This action critically degraded the aircraft's performance during a takeoff that was already compromised by a heavy payload and high density altitude. The runway conditions, with only a short mowed section available for takeoff roll on a grass surface, further limited the aircraft's ability to become airborne before striking obstacles.

Safety message

Pilots operating agricultural aircraft must ensure clear identification of controls when performing weight-reduction procedures during critical phases of flight. The confusion between flap and dump handles highlights the need for strict procedural discipline and possibly physical safeguards or checklist verification to prevent inadvertent configuration changes.

Probable cause

The pilot's failure to properly identify the control handle, resulting in the extension of full flaps during takeoff with a heavy load, which led to inadequate performance and collision with terrain.

Frequently asked questions

What happened in the 1986-05-29 Piper PA-25-235 accident near Lenox, IA?

A pilot died from burns after colliding with a fence and the ground during takeoff in an agricultural aircraft loaded with pesticide. The accident occurred on a grass runway with limited mowed area, exacerbated by high density altitude and nearby thunderstorm activity.

What aircraft was involved and where did it happen?

The accident on 1986-05-29 involved a Piper PA-25-235, registration N7029Z, operated by Hermes Service Inc, at Lenox, IA.

What was the probable cause of the accident?

The pilot's failure to properly identify the control handle, resulting in the extension of full flaps during takeoff with a heavy load, which led to inadequate performance and collision with terrain.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X33648. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.

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