HISTORY OF FLIGHT On July 7, 1994 at 1930 Alaska daylight time, a wheel equipped Piper PA-18-150 airplane, N8466Y, registered to and operated by the pilot, struck a ravine during the landing roll on the mud flats of the Fort Richardson impact area. The personal flight departed Merrill Field, Anchorage, Alaska for a local flight and no flight plan was filed. Visual meteorological conditions prevailed. The private certificated pilot, the sole occupant, was not injured and the airplane was substantially damaged. According to the pilot, he saw three people in a inflatable raft in survival suits and thought they needed help. He stated he saw an airstrip marked so he landed to give assistance. During the landing roll he struck a 15 foot deep tidal ravine. WRECKAGE AND IMPACT INFORMATION The on site examination showed that there was no marked airstrip located in the area where the pilot landed. However, surveyors working for wildlife biologists had surveyed a line in the area and marked the line with red flags. The survey line aligned with 180 degrees magnetic. The survey line was located in the Ft. Richardson artillery impact area known as Restricted Area R-2203A and R-2203B. Examination of the landing area showed tracks, which paralleled the survey line, on the right (west) side of the survey line. The area was flat and hard and covered with swamp grass ranging in length from 6 inches to 18 inches. The area was transected with tidal gullies and ravines which ranged in depth from 2 feet to 15 feet. The tracks, which paralleled the survey line, ran to the edge of a 15 foot deep tidal ravine. The ravine was 25 feet wide and was aligned with approximately an east/west heading. The airplane came to rest on the south side of the ravine on its nose, the main landing gear collapsed and both wings bent downward with the wingtips touching the ground. Examination of the airplane showed good flight control continuity to all the flight control surfaces. The fuel on board the airplane was blue in color and representative of 100 octane low lead aviation fuel. No external mechanical deficiencies on the engine were noted. ADDITIONAL INFORMATION The pilot was given a field sobriety test by the Ft. Richardson Military Police because they detected an odor of alcohol on the pilot's breath and person. The pilot failed the field sobriety test and would not submit to a breathalyzer test. He declined to submit a blood or urine sample for a toxicological test. According to the Military Police they administered an "HGN" test and during the test the pilot's eyes "displayed a lack of smooth pursuit" and maximum deviation occurred at 35 percent. The Military Police who initially responded to the accident scene were told by a wildlife observer that the pilot had made a number of trips from the airplane to points on the ground distant from the airplane. Examination of the area yielded a plastic six pack retainer which contained one full Budweiser can still attached to the plastic retainer. No empty beer cans were found in the airplane or around the immediate area. No evidence of any boaters needing assistance was found near the accident site. However, Knik Arm does run adjacent to the area where the pilot landed and boaters frequently use the area during the fishing season.