SURRY — The preliminary report released by the National Transportation Safety Board on the crash of an airplane into Morgan Bay last month suggests that the plane may have run out of fuel.
Late on the afternoon of Monday, Aug. 17, a small, bright yellow airplane made a crash landing off the beach on the eastern shore of Morgan Bay. The pilot and his one passenger were uninjured, and both were able to climb out of the plane and swim to shore. The plane sank in shallow water but was completely covered at high tide.
Five days after the accident, the aircraft was lifted from the water onto the salvage barge Charles Bradley and taken to the Southwest Harbor boatyard of The Hinckley Co., where it was met by an inspector from the Federal Aviation Administration.
Earlier this month, the National Transportation Safety Board released an Aviation Accident Preliminary Report on the incident based on the FAA inspector’s examination of the plane, a single-engine Cessna 150M two-seater, after it was removed from the barge.
According to the inspector, the plane suffered “substantial damage to the wings and fuselage.” Despite the damage, the inspector was able to rotate the engine by turning the propeller by hand.
The pilot told the inspector that he was en route from Vermont to the Hancock County-Bar Harbor Airport in Trenton and that the flight was “uneventful” until he began his descent for landing. He reported that, at about 1,400 feet above ground level, “the engine sputtered and lost power.” Although the pilot “pumped the throttle” and “rocked wings” the engine would not restart.
The pilot decided to attempt a landing on a beach on the shore of Morgan Bay but, seeing that the beach was rocky, “aimed for shallow water in the bay.”
The Cessna 150, last manufactured in 1977, is equipped with two fuel tanks in the wing, one on either side of the fuselage and cabin. The inspector’s report disclosed that the left fuel tank was empty of both fuel and salt water. The right tank was “about half full with diluted saltwater and an undetermined amount of fuel.” The “gascolator,” a fuel-water separator similar to those found on boats and mounted on the firewall separating the engine compartment from the cockpit, “contained about one gallon of fuel.”
In the cockpit, the inspector found the throttle and the control for the fuel-air mixture, similar to a choke, were found in the “full forward,” or maximum open, positions.
The inspector also found that the fuel selector that determines from which tank the engine draws gas was on. The carburetor heat lever was found in the off position.
While the preliminary report did not assign a cause for the accident, it spoke volumes to at least one professional aviator.
“I would be very comfortable stating that a highly probable cause was fuel-related,” Steve Pocock, a retired jet captain for a major U.S. airline, said last week. “On any airplane, there is always a small amount of residual, unusable fuel in the tank.”
According to a safety report published by the Aircraft Owners and Pilots Association, the Cessna 150 is “more prone to fuel exhaustion” — running out of gas — than other similar light aircraft.
The C150 Safety Review “was established in 2014 to address safety concerns” regarding aircraft and investigated more than 1,000 Cessna 150 accidents worldwide, according to the AOPA.
The review found that “fuel exhaustion due to pilots failing to comprehend the abnormally high quantity of unusable fuel…inaccurate fuel gauges and higher than anticipated fuel consumption” were among the leading causes of accidents in the Cessna 150.
The NTSB preliminary report suggests that the pilot, whose name has not been released, was not familiar with the aircraft he was flying.
According to the inspector, the plane’s “carburetor heat” control was found in the off position and the pilot “could not recall” how the control was set.
“He added that he was not accustomed to flying airplanes that required carburetor heat,” the inspector said.
Pocock, the retired airline pilot, said every small airplane with a carbureted piston engine has a carburetor heat control and checking that it is functioning correctly “is part of every pre-takeoff runup.”
In fact, carburetor heat is critical to safe operation of any airplane without fuel-injected engines.
“Because of the venturi action of the normally aspirated piston engine aircraft carburetor, temperature drop can cause moist air to freeze in the throat of the carburetor,” potentially restricting the flow of fuel to the engine, Pocock said. “This becomes a factor at lower power settings,” such as used during a descent prior to landing.
The NTSB has not announced when it would submit a final report on the Surry accident, but typically it takes about a year to complete an aviation accident investigation and final report.