What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Lake Berryessa and sank to bottom. (.4)the purpose of the flight was to fly over the lake with the intent of viewing the lake and surrounding area. The lake is 10 miles from the airport. Approximately 30 minutes into the flight the pilot noted a loss of fuel pressure followed by a rough running engine. He believed that the engine driven fuel pump had failed. He engaged the electric boost pump and the fuel pressure came back on-line and engine ran normally. The pilot decided to return to the airport to make a precautionary landing. He again noted that the fuel pressure gage needle began to move sporadically and the engine began to run rough and subsequently lost power. He made an unsuccessful attempt to restart the engine utilizing the in-flight engine failure checklist and subsequently ditched the airplane in the lake. No discrepancies were noted with the flight prior to the loss of engine power. The fuel system was inspected with no foreign debris found. A functional check was performed on the electric boost pump and no fuel flow output was observed; however, during the test the pump shorted out. Both the engine driven fuel pump and electric boost pump were sent out for further tests. Two functional checks were conducted on the engine driven fuel pump. An adjusting nut on the engine driven fuel pump allows for an increase or decrease in fuel flow. The first test was completed in the as-received condition with the adjusting nut loose. The results were consistently low, but fuel flow output was observed from the pump. The adjusting nut was then readjusted to overhaul specifications for the second functional check. The check revealed that the fuel flow was within overhaul specifications. During the teardown of the electric boost pump, it was noted that the bearings were loose allowing the pump vanes to rub up against the throat of the pump, decreasing fuel flowing through the fuel system. (-23)on local personal flight from travis arb aero club. Aircraft was in cruise flight over Lake Berryessa, CA when engine lost power. Pilot landed aircraft in lake. Aircraft sank in 40 feet of water. Both pilot and passenger were picked up by boat in area.
As the FAA filed it
LAKE BERRYESSA AND SANK TO BOTTOM. (.4)THE PURPOSE OF THE FLIGHT WAS TO FLY OVER THE LAKE WITH THE INTENT OF VIEWING THE LAKE AND SURROUNDING AREA. THE LAKE IS 10 MILES FROM THE AIRPORT. APPROXIMATELY 30 MINUTES INTO THE FLIGHT THE PILOT NOTED A LOSS OF FUEL PRESSURE FOLLOWED BY A ROUGH RUNNING ENGINE. HE BELIEVED THAT THE ENGINE DRIVEN FUEL PUMP HAD FAILED. HE ENGAGED THE ELECTRIC BOOST PUMP AND THE FUEL PRESSURE CAME BACK ON-LINE AND ENGINE RAN NORMALLY. THE PILOT DECIDED TO RETURN TO THE AIRPORT TO MAKE A PRECAUTIONARY LANDING. HE AGAIN NOTED THAT THE FUEL PRESSURE GAGE NEEDLE BEGAN TO MOVE SPORADICALLY AND THE ENGINE BEGAN TO RUN ROUGH AND SUBSEQUENTLY LOST POWER. HE MADE AN UNSUCCESSFUL ATTEMPT TO RESTART THE ENGINE UTILIZING THE IN-FLIGHT ENGINE FAILURE CHECKLIST AND SUBSEQUENTLY DITCHED THE AIRPLANE IN THE LAKE. NO DISCREPANCIES WERE NOTED WITH THE FLIGHT PRIOR TO THE LOSS OF ENGINE POWER. THE FUEL SYSTEM WAS INSPECTED WITH NO FOREIGN DEBRIS FOUND. A FUNCTIONAL CHECK WAS PERFORMED ON THE ELECTRIC BOOST PUMP AND NO FUEL FLOW OUTPUT WAS OBSERVED; HOWEVER, DURING THE TEST THE PUMP SHORTED OUT. BOTH THE ENGINE DRIVEN FUEL PUMP AND ELECTRIC BOOST PUMP WERE SENT OUT FOR FURTHER TESTS. TWO FUNCTIONAL CHECKS WERE CONDUCTED ON THE ENGINE DRIVEN FUEL PUMP. AN ADJUSTING NUT ON THE ENGINE DRIVEN FUEL PUMP ALLOWS FOR AN INCREASE OR DECREASE IN FUEL FLOW. THE FIRST TEST WAS COMPLETED IN THE AS-RECEIVED CONDITION WITH THE ADJUSTING NUT LOOSE. THE RESULTS WERE CONSISTENTLY LOW, BUT FUEL FLOW OUTPUT WAS OBSERVED FROM THE PUMP. THE ADJUSTING NUT WAS THEN READJUSTED TO OVERHAUL SPECIFICATIONS FOR THE SECOND FUNCTIONAL CHECK. THE CHECK REVEALED THAT THE FUEL FLOW WAS WITHIN OVERHAUL SPECIFICATIONS. DURING THE TEARDOWN OF THE ELECTRIC BOOST PUMP, IT WAS NOTED THAT THE BEARINGS WERE LOOSE ALLOWING THE PUMP VANES TO RUB UP AGAINST THE THROAT OF THE PUMP, DECREASING FUEL FLOWING THROUGH THE FUEL SYSTEM. (-23)ON LOCAL PERSONAL FLIGHT FROM TRAVIS ARB AERO CLUB. AIRCRAFT WAS IN CRUISE FLIGHT OVER LAKE BERRYESSA, CA WHEN ENGINE LOST POWER. PILOT LANDED AIRCRAFT IN LAKE. AIRCRAFT SANK IN 40 FEET OF WATER. BOTH PILOT AND PASSENGER WERE PICKED UP BY BOAT IN AREA.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.