Wsk Pzl Mielec M-18B N7643J accident near Caldwell, Idaho

Probable cause

The pilot’s improper decision to continue the takeoff with a tailwind after he recognized a performance problem with the airplane and his delayed action to dump the chemical load.

NTSB analysis

The pilot reported that, when he applied power for takeoff on an aerial application flight, the airplane seemed to accelerate normally until the tailwheel lifted off the ground. He adjusted the power lever forward, but the torque did not seem to increase. The pilot stated that, at that point, it was "unlikely" that the airplane would lift off the ground before it reached the end of the runway but that it was "too late to abort" the takeoff. The pilot advanced the power lever full forward and held it there. He then jettisoned the applicant load and simultaneously pulled back on the control stick. The main landing gear wheels lifted off the ground but the tailwheel did not. The airplane subsequently collided with a fence and came to rest in a river. A postaccident examination of the engine revealed no evidence of mechanical failures or malfunctions that would have precluded normal operation. An 8-knot tailwind existed at the time of the takeoff, which most likely resulted in the airplane's performance deficiency. The pilot further reported that "a more prompt recognition of the problem and an earlier decision to dump the load [of applicant] may possibly have prevented the aircraft from hitting the fence."

Text from the NTSB. Open the NTSB docket for WPR13LA308 for the full record.