Air Tractor Inc AT 401 N4549E accident near Wall, South Dakota

Probable cause

The pilot's failure to adjust the airplane's useful load to compensate for the high temperature, which resulted in an insufficient climb rate to clear surrounding terrain, and a runway excursion.

NTSB analysis

The pilot reported that during takeoff from a private grass airstrip, the airplane would not climb above terrain at the end of the runway and impacted the ground coming to rest in a wheat field. The airplane sustained substantial damage to the right wing, right aileron, and fuselage.

The pilot reported the outside air temperature at the time of the accident was 91 degrees Fahrenheit and the airplane was loaded near its maximum gross takeoff weight of 6,000 pounds. The pilot stated, "The load was too heavy for the weather conditions at this time".

The pilot reported no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for GAA15CA117 for the full record.