Event Description
During landing of a tail-wheel equipped airplane, the aircraft began to drift left of the runway centerline after touchdown. The commercial pilot was at the controls. The certified flight instructor (CFI) instructed the commercial pilot to use right aileron to correct the drift. The commercial pilot responded, "I've got it; I've got it; I've got it." The airplane subsequently departed the left side of the runway and onto the grass.
Control Inputs
The CFI then "stepped firmly" on the right rudder in an effort to straighten the airplane; however, the momentum continued pulling the airplane to the left. Without instruction from the CFI, the commercial pilot added full power, which was immediately followed by a reduction of power by the CFI. The airplane continued moving left, and the commercial pilot added about one-quarter to one-half power from where the CFI had set it.
Outcome
The airplane then rolled over and came to rest in a ditch.
Pilot Comment
The commercial pilot added that the accident could have been prevented by "earlier recovery, more experience by pilot and instructor."