According to the flight instructor, the commercial pilot receiving instruction was practicing takeoffs and landings on a 900-foot-by-20-foot dirt airstrip in the tailwheel-equipped airplane. Due to the topography, landings at the airstrip are made to the south and takeoffs are made to the north. During the flight, the wind picked up to about 4 to 5 knots from the northwest, resulting in a right quartering tailwind for landing. During what was planned to be the last landing at the airstrip, the commercial pilot did not arrest the descent quickly enough, and the airplane bounced on touchdown and drifted left. The flight instructor called for full power and took control of the airplane. He maneuvered the airplane back towards the center of the airstrip, reduced power, and landed with the left main gear 1 foot off the left side of the airstrip and the right main near the middle of the airstrip. He said that he applied the brakes heavily and the airplane began to slow; however, the right main skidded on some hard bedrock, and before the flight instructor could get off the brakes, the airplane nosed over. Both wings and the vertical stabilizer sustained structural damage. The flight instructor commented that the accident could have been prevented "if we had quit landing there when the winds picked up."