What happened
On January 4, 2010, a Cessna 172S, registration N5118J, crashed into the Penobscot River near Greenbush, Maine. The aircraft, operated by American King Air Services, Inc., was on an instrument flight rules (IFR) ferry flight from Bangor International Airport (KBBGR) to Goose Bay Airport (CYYR) in Canada. The ultimate destination for the aircraft was Russia.
Shortly after takeoff, the pilot reported difficulty maintaining altitude, stating the aircraft was "a bit heavy" and requesting to level off at 6,000 feet mean sea level. Approximately five minutes later, the pilot informed air traffic control that the aircraft was experiencing severe turbulence and was having control difficulties. The pilot subsequently requested to return to Bangor.
Radar data showed the aircraft traveled approximately 25 miles northeast of the departure airport before reversing course near Enfield, Maine. During the return, the aircraft descended from 6,000 feet to approximately 1,200 feet before radar contact was lost. A witness reported seeing the aircraft fly overhead at an altitude of approximately 100 feet above ground level with continuous engine noise before the sound of impact was heard.
The investigation
The investigation examined the wreckage, which was recovered from the ice-covered river. The aircraft had been equipped with an auxiliary fuel tank for the transoceanic flight, which increased the maximum gross takeoff weight to 3,315 pounds—30 percent higher than the manufacturer's published maximum of 2,550 pounds. This increased weight was authorized under a special airworthiness certificate.
Mechanical examination of the N5118J revealed no evidence of preimpact mechanical failure. The engine's compression was normal, and the ignition system was intact. The aircraft's operating limitations specifically stated to "Avoid moderate to severe turbulence."
Findings
- The pilot was operating an aircraft with a gross weight 30 percent above the standard maximum gross weight.
- At the time of the accident, AIRMETs for moderate turbulence and moderate ice were in effect for the flight route.
- The pilot was aware of the weather conditions, including the presence of clouds and precipitation, prior to departure.
- The pilot experienced extreme turbulence and difficulty maintaining control of the aircraft.