On June 30, 1997, at 1730 eastern daylight time, a Cessna 172P, N97613, was substantially damaged during a hard landing at the Bear Crik Airstrip (42PA), Tioga, Pennsylvania. The certificated private pilot and two passengers were not injured, while a third passenger received minor injuries. Visual meteorological conditions prevailed for the personal flight that departed Wellsboro, Pennsylvania, about 1715. No flight plan had been filed for the flight conducted under 14 CFR Part 91. In the NTSB Form 6120.1/2, the pilot stated that he departed 42PA with three passengers for a local flight. After takeoff, the airspeed indicator failed, and he diverted to the Grand Canyon State Airport, Wellsboro. The pilot removed mud from the pitot tube and refueled the airplane. He then departed with the passengers for 42PA, and en route, the airspeed indicator failed again. The pilot further stated: "...As 42PA has 50ft obstacle on one end, I elected to land downwind...I made a low and as slow an approach...Upon landing I found I was to fast and applied full brakes on uneven terrain. Front wheel broke off and I held the airplane up...When the front came down, the gear post dug into the strip and the aircraft flipped on it's back..." Examination of the airplane and the grass strip by a Federal Aviation Administration Inspector revealed that the airplane touched down in the first one third of the runway. The Inspector's report stated that the airplane bounced and touched down about 1,000 feet from the approach end of the runway. It then became airborne again, touched down 500 feet later, and the nose wheel dug into the dirt and the airplane nosed over. Examination of the pitot tube by the FAA Inspector revealed that it was blocked with mud. The published airport data for 42PA listed runway 3/21, as 1,600 feet long, with no obstacles at either end of the runway. An airport 18 miles northeast of 42PA reported the winds from 170 degrees at 9 knots.