Great Lakes 2T1A N3512L accident near Montague, Massachusetts

Probable cause

The pilot’s failure to maintain directional control during the attempted takeoff, which resulted in a runway excursion.

NTSB analysis

The private pilot was initiating takeoff for the positioning flight with no winds and with the airplane's tail off the runway when the airplane suddenly veered left, which he could not correct. The airplane exited the left side of the runway and then slid down a sharp incline into a ditch and nosed over.

Postaccident examination of the runway revealed skid marks made by the right main landing gear (MLG) tire that continued off the runway, and by the tailwheel tire, which began 50 ft past the beginning of the right MLG tire marks and also continued off the runway. The left MLG tire only made light tire marks, which indicates that the airplane was light on the left MLG tire during the takeoff.

No flat spots were noted on either MLG tire, and examination of both brakes and the flight controls revealed no evidence of a preimpact mechanical malfunctions or failures that would have precluded normal operation. During an operational test, the left brake operated normally. The right brake could not be operationally tested due to damage to its components Given the evidence, it is likely that the pilot lost directional control during the attempted takeoff.

Text from the NTSB. Open the NTSB docket for ERA18LA023 for the full record.