Accident Overview
An aircraft conducting a trans-Pacific flight experienced a fuel transfer problem approximately 4 hours into the journey. The crew reported the issue to air traffic control (ATC), initially considering a turn-around, then declaring an emergency. They stated they had 10 hours of fuel remaining but could access only about 2 hours.
Flight Path and Ditching
Satellite flight track data showed the aircraft reversed course when it was about 356 miles from the California coast. About 132 miles from the coast, the altitude decreased to approximately 4,000 ft above mean sea level (msl). In the final minutes, the altitude dropped from about 3,600 ft msl to around 240 ft msl. The last data point was located about 33 miles off the California coast.
Wreckage and Recovery
The United States Coast Guard (USCG) responded to the accident location. They reported the fuselage was inverted in the water, with the wings and engines separated from the fuselage. The pilots were still strapped in their seats and were unresponsive. The occupants were not recovered. Search efforts recovered the nose landing gear, right wing, and right engine. A fuel bladder tank had washed ashore in southern California.
Postaccident Examination
Postaccident examination of the recovered components revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.
Ferry Fuel System Installation
A mechanic reported that he was instructed to set up the ferry fuel tank system on the accident aircraft. He installed the system but did not fill it with fuel, as he did not know when the flight would take place and considered it unsafe to have the bladders contain fuel for several days. After installation, he contacted the copilot (who was also a mechanic), who was then to complete the installation. The mechanic understood that the copilot would be responsible for the final installation and appropriate logbook entries. The mechanic was not present when the copilot completed the installation and was not sure if the copilot had signed off on it.
Probable Cause
The failure of the ferry fuel tank system to transfer fuel during a trans-Pacific flight for reasons that could not be determined, which resulted in fuel starvation and a subsequent ditching into the water.