Accident Overview
On May 17, 2019, about 1515 eastern daylight time, a Cessna P210N airplane, registration N4861P, was substantially damaged when it was involved in an accident in the Gulf of Mexico near Yankeetown, Florida. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
Flight Details
The pilot reported verifying fuel quantities before departure using a calibrated dip tube: the left wing fuel tank contained about 30 gallons, the right wing about 40 gallons, with an estimated usable fuel load of at least 68 gallons (about 4 hours of fuel). The estimated time en route from Sebastian Municipal Airport (X26), Sebastian, Florida, to De Funiak Springs Airport (54J), De Funiak Springs, Florida, was about 3 hours.
No anomalies were noted during the preflight check or engine runup. After a normal takeoff, the pilot retracted flaps and landing gear, reduced power to 21 inches of manifold pressure at 2,400 rpm, and leaned the mixture to a turbo inlet temperature of 1,300° F while cruising at 2,500 ft mean sea level (msl).
Electrical and Engine Issues
About 1 hour into the flight, the pilot switched from the right-wing fuel tank to the left. Approximately 45 minutes later, the airplane experienced a total loss of electrical power at 2,500 ft msl over the Gulf of Mexico. The pilot cycled the battery/alternator switch and inspected circuit breakers, but could not restore electrical power. He turned toward Crystal River Airport (CGC) for a precautionary landing and manually extended the landing gear using the emergency hand pump; the down-and-locked green indicator light did not illuminate due to the power loss.
The pilot then switched from the left-wing fuel tank to the right, which contained more fuel. After increasing the fuel mixture to full rich and selecting maximum propeller speed, the engine continued running normally. However, about 1-2 minutes after gear extension, the airplane suffered a total loss of engine power suddenly and without warning. The propeller continued windmilling. The pilot reported not switching fuel tanks or attempting an engine restart, as he was focused on ditching.
Ditching and Rescue
The pilot ditched the airplane in the Gulf of Mexico about 5 miles offshore. The airplane initially stayed afloat but became partially submerged within 15 minutes. The aircraft was not equipped with a life raft or life preservers. After submersion, the pilot could not swim fast enough to keep up with the drifting airplane. He drifted and swam with the current for over 11 hours, coming ashore on an unpopulated barrier island around 0300 the following morning. Between 0600 and 0700, he signaled a fishing boat, which contacted the United States Coast Guard. The pilot was retrieved from the island about 0800 and admitted to a local hospital for severe dehydration.
Post-Accident Examination
The airplane was examined by an FAA airworthiness inspector. The right horizontal stabilizer and right elevator were substantially damaged. Additional damage resulted from towing, recovery, and saltwater immersion. The wings were removed for transport; trailing edge damage from recovery straps was noted. The right-wing fuel tank filler cap was missing during examination, though photographs showed it present before recovery. No fuel was observed in either wing fuel tank. The left wingtip auxiliary tank contained about an ounce of fuel; the right wingtip tank was not recovered. The cockpit fuel selector valve was positioned to the right-wing tank. Fuel reservoir tanks in the lower fuselage contained murky water. Uncontaminated fuel was found in the fuel strainer and from a fuel line between the engine’s fuel manifold and fuel control unit.
Engine examination revealed no evidence of mechanical malfunction or failure. The engine was attached to mounts, with no fire or heat damage. Engine control continuity was verified. Internal examination showed compression and suction on all six cylinders. Spark plug leads were saltwater-contaminated. Both magnetos produced an audible snap when the crankshaft was rotated, but the ignition key switch was seized in the off position, grounding both magnetos. The alternator input shaft rotated with the crankshaft.
Examination of the electrical system found that the battery’s positive power cable was loose at the battery contactor terminal (p/n S-1580A1). The securing nut was significantly smaller than the nut on the terminal for the battery switch and starter motor contactor cables. No washers were present, and the nut had backed off about two threads, resulting in a loose connection.