On June 28, 2003, at 1100 eastern daylight time, a Maule M-4-220C, N2030U, was substantially damaged while landing at the Taunton Municipal Airport (TAN), Taunton, Massachusetts. The certificated flight instructor (CFI), certificated commercial pilot, and one passenger, were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the flight, which originated from the Barnstable Municipal-Boardman/Polando Field (HYA), Hyannis, Massachusetts. The instructional flight was conducted under 14 CFR Part 91. According to the CFI, the commercial pilot was at the controls of the tail-wheeled airplane during the accident flight. As the airplane touched down on runway 30, a 3,500-foot long, 75-foot wide, asphalt runway, it began to drift left of centerline. The CFI instructed the commercial pilot to use right aileron to correct the situation, which the commercial pilot responded, "I've got it; I've got it; I've got it." The airplane departed the left side of the runway, and onto the grass. The left wheel then began to slow, pulling the airplane to the left, and dipping the left wing. The CFI "stepped firmly" on the right rudder in an effort to straighten the airplane; however, the momentum was still pulling the airplane to the left. Without the CFI's instruction, the commercial pilot added full power, followed immediately by a reduction of power by the CFI. The airplane continued to the left, and the commercial pilot added about one-quarter to one-half power from where the CFI had set it. The airplane then rolled over, and came to rest in a ditch. The commercial pilot added that the accident could have been prevented by "earlier recovery, more experience by pilot and instructor." The winds recorded at the airport, about the time of the accident, were from variable at 6 knots.