History of Flight
On June 18, 2010, at 1703 eastern daylight time, a Cessna 401, registration N401TE, operated by Global Data Aviation, was substantially damaged when it collided with trees and terrain after a total loss of engine power while maneuvering for landing at Plymouth Municipal Airport (PYM), Plymouth, Massachusetts. The certificated airline transport pilot and two passengers were seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the flight, which departed PYM at approximately 1355. The aerial mapping flight was conducted under 14 Code of Federal Regulations Part 91.
Two witnesses in close proximity to the airport observed the airplane at low altitude relative to other aircraft on the same approach. One witness heard the engine noise cease as the airplane passed overhead and subsequently heard the sounds of impact. Upon arrival at the scene, no smoke or gas fumes were detected, and the occupants were alert but trapped in their seats. The pilot later informed the witness that he lost engine power and could not restart due to low altitude.
The operator reported that the pilot stated both engines lost power and could not be restarted.
In a telephone interview on June 25, 2010, and a subsequent written statement, the pilot reported that the aerial mapping flight was suspended due to suboptimal sun angle for the camera, prompting a return to PYM. Approximately 8 miles from the destination, the pilot cancelled flight following services, radioed that he was inbound, and established a 5-mile straight-in visual approach to runway 24.
About 3 miles out on final approach, just before the final landing check, one engine lost power, followed almost immediately by the second. The pilot switched from auxiliary to main fuel tanks, confirmed mixture controls were full forward, placed the electric fuel pump on low, checked the magnetos, and observed the fuel gauges. The auxiliary tank gauges fluctuated between 2 and 5 gallons, while the main tanks indicated about 25 gallons per side. The engines were windmilling but would not restart despite attempts using the starters. By the time the pilot completed his remedial actions, the airplane had descended to approximately 200 feet above ground level, and the engines could not be restarted. He selected a forced landing site between two large trees and landed in heavily wooded terrain.
Personnel Information
According to Federal Aviation Administration (FAA) records, the pilot held an airline transport pilot certificate with ratings for airplane multiengine land and a commercial pilot certificate with a rating for airplane single engine land. His most recent FAA first-class medical certificate was issued in October 2009. He reported 3,500 total flight hours, with 1,200 hours in the accident aircraft make and model.
Aircraft Information
The airplane was manufactured in 1968 and had accrued 13,252 total aircraft hours. Its most recent annual inspection was completed on June 1, 2010, at 13,231 hours. According to the pilot and fuel purchase records, the airplane departed on the accident flight with full fuel tanks.
Meteorological Information
At 1652, the weather conditions reported at PYM were clear skies, visibility 10 miles, wind from 210 degrees at 12 knots gusting to 22 knots, temperature 25°C, dewpoint 14°C, and barometric pressure 30.04 inches of mercury.
Wreckage and Impact Information
The airplane wreckage came to rest in wooded terrain, and all major components were accounted for. The wreckage path was oriented about 180 degrees. Both wings were separated from the aircraft outboard of the engine nacelles through the auxiliary fuel tank areas, exhibiting multiple impact marks from striking trees. The fuselage structure was relatively intact. The cockpit seats and seat number 3 were attached to the floor rails; seat number 4 was removed by first responders. No shoulder harnesses were installed, and the lap belts were intact and unlatched.
Flight control cable continuity was established from the cockpit controls to the flight control surfaces. The flap actuator measurement equated to a retracted setting. The horizontal stabilizer, elevators, and elevator trim tab were separated from the airplane, attached only by the elevator trim tab cables. The estimated elevator trim tab measurement equated to a setting greater than 6 degrees tab up.
The fuel selector handles were in the OFF position, and both valves were separated from the wings with damage consistent with impact. Both propellers were separated from their respective engines and showed little to no signatures of rotation at impact. According to the pilot, he placed the fuel selectors in the off position at the request of first responders.
Additional Information
An excerpt from the Cessna 401 Owner's Manual describes the before-landing checklist, including selecting the main fuel tanks, and information on the optional auxiliary fuel system. The manual notes that operation near the ground (below 1,000 feet) using auxiliary fuel tanks is not recommended.