Narrative:

A precautionary landing was made on the mouth of the nestucca river after an unexplained loss of power resulted in a loss of altitude, and an inability to reach the destination airport. Following a descent from 6500 in VFR conditions, with carburetor heat on, a significant loss of power was noticed upon leveling off at 2500 MSL. Mixture was full rich, carburetor heat applied again, fuel selector doublechked for 'both,' but there was still not sufficient power to sustain altitude. The glide that was established was not able to take me to the airport 3 mi away, and would put me in the river if corrective action was not taken immediately. The only acceptable landing spot was the shore line with a long flat stretch of sand along the mouth of the nestucca river. No persons or property were located anywhere around, and the turn and descent was made. A safe, soft touchdown was made, and the occupants were uninjured. The sand was soft, and the airplane had to be towed off the beach to the pacific city airport.

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Original NASA ASRS Text

Title: PVT PLT OF AN SMA GA ACFT MADE A FORCED OFF ARPT LNDG AFTER LOSING PWR DURING DSCNT FOR LNDG.

Narrative: A PRECAUTIONARY LNDG WAS MADE ON THE MOUTH OF THE NESTUCCA RIVER AFTER AN UNEXPLAINED LOSS OF PWR RESULTED IN A LOSS OF ALT, AND AN INABILITY TO REACH THE DEST ARPT. FOLLOWING A DSCNT FROM 6500 IN VFR CONDITIONS, WITH CARB HEAT ON, A SIGNIFICANT LOSS OF PWR WAS NOTICED UPON LEVELING OFF AT 2500 MSL. MIXTURE WAS FULL RICH, CARB HEAT APPLIED AGAIN, FUEL SELECTOR DOUBLECHKED FOR 'BOTH,' BUT THERE WAS STILL NOT SUFFICIENT PWR TO SUSTAIN ALT. THE GLIDE THAT WAS ESTABLISHED WAS NOT ABLE TO TAKE ME TO THE ARPT 3 MI AWAY, AND WOULD PUT ME IN THE RIVER IF CORRECTIVE ACTION WAS NOT TAKEN IMMEDIATELY. THE ONLY ACCEPTABLE LNDG SPOT WAS THE SHORE LINE WITH A LONG FLAT STRETCH OF SAND ALONG THE MOUTH OF THE NESTUCCA RIVER. NO PERSONS OR PROPERTY WERE LOCATED ANYWHERE AROUND, AND THE TURN AND DSCNT WAS MADE. A SAFE, SOFT TOUCHDOWN WAS MADE, AND THE OCCUPANTS WERE UNINJURED. THE SAND WAS SOFT, AND THE AIRPLANE HAD TO BE TOWED OFF THE BEACH TO THE PACIFIC CITY ARPT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.