Narrative:

Departed as 2 ships; in-trail. 1 or 2 mi offshore; I took the lead. Cruise power; mixture normal; 2000 RPM. Could not find sweet spot in RPM at smooth running engine. Engine got rougher gradually; I headed toward ZZZ1. Vibration worse; and then sump light came on. Engine backfired. I told ZZZ1 I was heading for ZZZ2 and declared an emergency. Engine rougher. I headed down the coastline. I realized I could not make ZZZ2. I told ZZZ1 tower was heading for the beach. I told my passenger to check shoulder harness locked. About 300 ft; all engine ignition stopped after loud bang. I turned fuel off. I dropped flaps as I turned on shore. We bounced once while aircraft was still controllable in flight and then stayed on the sand the second time we touched down; yawing about 50 degrees to the right as we slid to a stop. We then climbed out of the cockpit. The wind of about 250 degrees/10 KTS on shore contributed to the yaw. It helped me to have frequency (VHF communication) switched by button on yoke. Vibration was so bad; dialing frequency was impossible. To lessen threat of vibration breaking off engine; consideration should have been given to killing engine sooner. Callback conversation with reporter revealed the following information: the aircraft has not been repaired since the incident due to damage incurred during its retrieval from the beach. Gear up is the proscribed method of landing this aircraft on soft surfaces.

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Original NASA ASRS Text

Title: T28 PILOT REPORTS ENGINE FAILURE WHILE FLYING JUST OFF SHORE AT 3500 FEET. ACFT IS SAFELY LANDED GEAR UP ON THE BEACH WITH NO INJURIES.

Narrative: DEPARTED AS 2 SHIPS; IN-TRAIL. 1 OR 2 MI OFFSHORE; I TOOK THE LEAD. CRUISE PWR; MIXTURE NORMAL; 2000 RPM. COULD NOT FIND SWEET SPOT IN RPM AT SMOOTH RUNNING ENG. ENG GOT ROUGHER GRADUALLY; I HEADED TOWARD ZZZ1. VIBRATION WORSE; AND THEN SUMP LIGHT CAME ON. ENG BACKFIRED. I TOLD ZZZ1 I WAS HEADING FOR ZZZ2 AND DECLARED AN EMER. ENG ROUGHER. I HEADED DOWN THE COASTLINE. I REALIZED I COULD NOT MAKE ZZZ2. I TOLD ZZZ1 TWR WAS HEADING FOR THE BEACH. I TOLD MY PAX TO CHK SHOULDER HARNESS LOCKED. ABOUT 300 FT; ALL ENG IGNITION STOPPED AFTER LOUD BANG. I TURNED FUEL OFF. I DROPPED FLAPS AS I TURNED ON SHORE. WE BOUNCED ONCE WHILE ACFT WAS STILL CONTROLLABLE IN FLT AND THEN STAYED ON THE SAND THE SECOND TIME WE TOUCHED DOWN; YAWING ABOUT 50 DEGS TO THE R AS WE SLID TO A STOP. WE THEN CLBED OUT OF THE COCKPIT. THE WIND OF ABOUT 250 DEGS/10 KTS ON SHORE CONTRIBUTED TO THE YAW. IT HELPED ME TO HAVE FREQ (VHF COM) SWITCHED BY BUTTON ON YOKE. VIBRATION WAS SO BAD; DIALING FREQ WAS IMPOSSIBLE. TO LESSEN THREAT OF VIBRATION BREAKING OFF ENG; CONSIDERATION SHOULD HAVE BEEN GIVEN TO KILLING ENG SOONER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE ACFT HAS NOT BEEN REPAIRED SINCE THE INCIDENT DUE TO DAMAGE INCURRED DURING ITS RETRIEVAL FROM THE BEACH. GEAR UP IS THE PROSCRIBED METHOD OF LANDING THIS ACFT ON SOFT SURFACES.

Data retrieved from NASA's ASRS site as of January 2009 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.