BFO94FA163

While in cruise flight in a level six thunderstorm over the atlantic ocean, the pilot reported the airplane's 'gyro' had failed. The airplane then began a left turn and disappeared off radar. The airplane and its occupants were located on the ocean floor about 48 days after the accident. The airplane had broken apart in-flight. The outboard section of each wing and the tail section were not recovered. The airplane's pneumatic system was destroyed. According to fss records, the pilot had been briefed on the weather along his route of flight.

History of flight

On August 14, 1994, about 2310 eastern daylight time, a Piper, PA-601P, N3642A, collided with the water of the Atlantic Ocean, about 37 miles southeast of Sea Isle City, New Jersey. Thunderstorm and instrument meteorological conditions prevailed. A portion of the airplane and its occupants were located and recovered from the ocean floor on October 1, 1994, at a latitude of 38 degrees 48.4 minutes north and a longitude of 74 degrees 16.65 minutes west. The airplane was destroyed. The personal flight originated from North Myrtle Beach, South Carolina, about 2128, and was destined for Oxford, Connecticut. An instrument flight rules flight plan was on file for the flight. The flight was conducted under 14 CFR Part 91.

According to Washington Air Route Traffic Control Center (ARTCC) personnel, the flight departed North Myrtle Beach and continued North along the east coast with no reported unusual events. Washington ARTCC communications tape transcription revealed that at 2230, about one hour after departure, the pilot was in radio contact with the Washington ARTCC R54 sector controller and was advised of weather along his planned route of flight (along the east coast direct to MANTA intersection, direct to Oxford). The pilot stated, "Okay uh four two alpha will accept uh whatever routing you think might be uh better from this point." The R54 controller responded, "...I'm not sure how far out over the water you're gonna need to deviate so I mean I don't uh and if you go around the west side of the weather I'm not sure that you can even get in from that direction I don't know what the weather's like up at Oxford right now." The pilot acknowledged the transmission and reported that his airplane was equipped with weather radar. The pilot requested and was cleared to deviate 20 degrees to the east. The R54 controller also cleared N3642A to fly direct to the MANTA intersection (located about 75 miles northeast of Sea Isle City, New Jersey) "when able."

After about one hour and thirty minutes of flight (2256:41), about 37 miles southeast of Sea Isle City, New Jersey, at an assigned altitude of 19,000 feet, N3642A was handed off to the R58 sector controller who observed the airplane on radar tracking a southerly heading. When the pilot did not make radio contact with the R58 controller, the controller contacted the R54 controller and asked if he (the R54 controller) would try to contact the pilot. At 2301:15, the R54 controller made radio contact with the pilot and requested a position report. The pilot responded, "...Alpha has serious problems we lost gyro." About 33 seconds later, the controller stated, "...if you read the center uh uh suggest you uh southerly heading try...heading down towards Norfolk away from the weather."

At 2302:07, the pilot made an unintelligible transmission. This was the last recorded radio transmission made by the pilot and several attempts to reestablish radio contact with the pilot were unsuccessful.

National Tracking Analysis Program (NTAP) secondary radar data from the Washington ARTCC revealed the airplane was tracking northeasterly over the Atlantic Ocean, about 37 miles southeast of Sea Isle City, at 19,000 feet, when at 2300:20 the airplane began a left turn. The airplane continued a left turn and disappeared off radar at 2301:20.

Personnel information

The pilot held a private pilot certificate with single engine and multiengine land ratings. He also held an instrument airplane rating. The pilot's log book was not recovered. According to Federal Aviation Administration (FAA) records, at the time of the pilot's last application for an FAA medical certificate, dated February 18, 1994, he had accumulated a total of 1,275 flight hours.

According to a certificated flight instructor (CFI), he gave the pilot a Biennial Flight Review in N3642A sometime in the month of March, 1994. The CFI stated that he was a friend of the pilot and gave the BFR as a favor and therefore did not record it in his own log book.

Aircraft information

The airframe and engine received an annual inspection on August 3, 1994, at a tachometer time of 1458.3 hours. The tachometer was not found in the airplane wreckage.

Meteorological information

Two Convective SIGMETs were issued by the National Severe Storms Forecast Center at Kansas City, Missouri, applicable to the route of flight of N3642A:

Issued August 14, 2155 EDT Convective SIGMET 5E Valid until August 14, 2355 EDT DE MD VA and Coastal Waters Line thunderstorms 30 miles wide moving from 270 degrees at 25 knots. Tops above 45,000 feet. Hail to 2 inches...wind gusts to 70 knots possible.

Issued August 14, 2255 EDT Convective SIGMET 9E Valid until August 15, 0055 EDT MD VA and Coastal Waters Line thunderstorms 30 miles wide moving from 300 degrees at 20 knots. Tops above 45,000 feet.

According to Anderson Automated Flight Service Station records, the pilot received two weather briefings prior to the flight. During the second briefing the pilot was given information on the above reported Convective SIGMET 9E.

Weather satellite information indicated N3642A was in the thunderstorm referred to in SIGMETs 5E and 9E when radio and radar contact were lost.

Wreckage and impact information

A portion of the airplane was recovered from the ocean floor on October 1, 1994. Examination of the wreckage revealed that the fuselage, cabin area, and sections of the left and right wing with their respective engines were recovered. The tail section and outboard sections of both wings were not recovered.

The instrument panel was destroyed. The directional gyro was not recovered. The attitude indicator was recovered and the gyro casing was dismantled. The inside and outside of the gyro casing was eroded. The airplane's pneumatic system operating the gyro's was destroyed. Throttle, mixture, and propeller control levers were damaged and no reliable information was obtained.

The main fuselage was crushed and torn and the windows were missing. The outside, top portion of fuselage skin was flattened, dimpled, wrinkled, and crushed, indicative of hydrofoiling. Fuselage skin below the floor board was intact.

The left wing was separated just outboard of the engine and the outboard section of the wing was not recovered. The flap was found attached but due to the damage a flap setting could not be determined. The left wing's upper surface skin was wrinkled, dimpled, and crushed, indicative of hydrofoiling. The lower skin surfaces were crushed. The forward spar was elongated and stretched upward, and fracture surfaces revealed evidence of overstress separation.

The left engine and its accessories were damaged and corroded. The magnetos, vacuum pump, and oil filter were not recovered. The propeller assembly was attached to the engine. Two of the three blades were twisted in a clockwise direction.

The right wing was separated just outboard of the engine and the outboard section of the wing was not recovered. The flap was found pulled away from the wing structure but remained attached to the wing by debris. The wing's forward spar fracture surfaces revealed features of overstress separation. The forward spar failure direction was not determined. Structure surrounding the spar was bent upward and aft.

The right engine and its accessories were damaged and corroded. The magnetos and oil filter were not recovered. The vacuum pump was recovered and examined. The vacuum pump was broken away from the engine mount. The engine driven shaft to the pump was missing and the flexible coupling had been separated from its other half. The pump's rotor and vanes were broken. The propeller assembly was attached to the engine. The propeller blades were feathered. Two of the three propeller blades were bent opposite of operating rotation.

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