On July 6, 2003, about 1400 Alaska daylight time, a tailwheel-equipped Cessna 170B airplane, N63DJ, received substantial damage when it collided with terrain while on final approach to land at an off airport site, about 15 miles east-southeast of Palmer, Alaska. The airline transport certificated pilot and the sole passenger were not injured. The Title 14, CFR Part 91 personal flight operated in visual meteorological conditions without a flight plan. The local flight departed a private airstrip near Chugiak, Alaska, at 1320. The accident pilot had a telephone interview with an NTSB investigator on July 6. The pilot related that he was on final approach to land on a river bar near the Knik River, when it became apparent that the airplane was too low. He said he applied engine power, but the engine did not respond immediately, and the airplane descended into a shallow area of the river. The airplane rolled a short distance on touchdown, and then nosed over, sustaining structural damage to the wings, rudder, and vertical stabilizer. In the pilot's written statement to the NTSB, he reported that he was attempting to land on a river bar with a cut bank. He did not indicate the engine had a mechanical problem, but noted that after a prolonged power-off approach to the landing site, as he applied power to flare and "to make the landing spot," the engine "hesitated or sputtered." He reported that when the engine sputtered, he turned left, to avoid striking the cut bank. The airplane subsequently descended into the river and nosed over.