On October 27, 2003, at 1850 Pacific standard time, a Cessna 172M, N80628, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided with trees and subsequently the terrain while on final approach to Bandon State Airport, Bandon, Oregon. Night visual meteorological conditions prevailed at the time and no flight plan was filed for the local flight. The aircraft was substantially damaged and the private pilot, the sole occupant, was not injured. The pilot reported that he was practicing full stop landings in night conditions for currency requirements. The pilot stated that one landing had been accomplished without incident. During the second approach to runway 34, the pilot reported that the runway lights were lit and on low brightness, and the runway end identifier lights (REIL) were visible while on base and final approach. The pilot stated that while on final approach, he noted on the precision approach path indicator (PAPI) lights, that three of the four were red with the fourth light pink fading to white when the aircraft suddenly collided with trees. The aircraft subsequently collided with the ground, coming to rest inverted about 1/2 mile from the end of the runway. The Airport/Facility Directory for Bandon State indicates that runway 34 PAPI is equipped with four identical light units placed on the left side of the runway. An approach slope angle is not indicated, however, a threshold crossing height of 40 feet is indicated to clear trees. The Aeronautical Information Manual (AIM) indicates that for a four light unit PAPI, three red light units and one red light unit indicates a slightly low glide slope (2.8 degrees). Four red light units indicates low on the glide slope (less than 2.5 degrees). The pilot further reported on the NTSB Pilot/Operator Aircraft Accident Report Form 6120.1/2, "Review PAPI's for correct beam transmission." The U.S. Naval Observatory Sun and Moon Data for October 27, 2003, indicated sunset was at 1717, with end of civil twilight at 1746. The moon was waxing crescent with 8% of the Moon's visible disk illuminated.