On August 12, 1985, a Cessna 177 (registration N30232) was involved in an aviation accident near Vieques, PR. Investigators recorded the probable cause as: The engine failure due to fuel exhaustion resulting from inadequate preflight fuel planning. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A flight training aircraft suffered an in-flight engine failure caused by insufficient fuel. The occupants survived the water landing with assistance from a military helicopter.
What happened
During preflight preparations, the certified flight instructor (CFI) and the student pilot relied on a homemade dipstick to measure the fuel quantity in the aircraft's tanks. Based on this measurement, they determined that the tanks contained approximately eight gallons of fuel. Following takeoff, the aircraft remained airborne for about 30 minutes before the engine experienced a complete failure. The crew attempted to restart the engine multiple times, but all efforts were unsuccessful.
As the situation became critical, the pilot broadcast a 'Mayday' call prior to impact. The aircraft was subsequently ditched in approximately 25 feet of water. Despite the loss of power and the emergency landing, both occupants were recovered from the water by a military helicopter.
Probable cause
The engine failure due to fuel exhaustion resulting from inadequate preflight fuel planning.