N421RXCessna 421C

On November 22, 2017, about 1845 eastern standard time, a Cessna 421C, N421RX, was substantially damaged during a forced landing shortly after takeoff from Northern Maine Regional Airport (PQI), Presque Isle, Maine. The commercial pilot was not injured; two crewmembers, and one passenger sustained minor injuries. The airplane was operated by Fresh Air LLC under the provisions of Title 14 Code of Federal Regulations part 135 as an air medical flight. Day, instrument meteorological conditions prevailed, and an instrument flight rules flight plan was filed. The flight originated at PQI about 1840 and was destined for Bangor International Airport (BGR), Bangor, Maine.The pilot reported that the preflight inspection of the airplane and ground operations were uneventful. After taking off on runway 19, the pilot retracted the landing gear and turned off the landing lights. He then observed flames coming from the left engine nacelle. He immediately retarded the throttle and turned off the fuel boost pump; however, the fire persisted. He feathered the propeller, shut down the engine, and maneuvered the airplane below the clouds to remain in the traffic pattern at PQI. He attempted to keep the runway environment in sight while drifting in and out of clouds. He was unable to align the airplane for a landing on runway 19, so he attempted to land on runway 10. The pilot realized the airspeed was dropping and the airplane would not reach runway 10, so he landed in an adjacent field. After touchdown, the landing gear broke away and the airplane came to a stop in the grass.

The PQI reported weather at 1848 included, overcast clouds at 1,400 ft and broken clouds at 800 ft, with 5 statute miles visibility in light snow and mist. The pilot reported that the clouds were at 500 ft with rain and snow at the time of the accident.

An inspector with the Federal Aviation Administration responded to the accident site and examined the wreckage. The airplane came to rest in an upright position. The landing gear were separated, and structural damage to the wings and lower fuselage was evident. Initial examination of the left engine revealed soot on the nacelle louver vents and some localized white discoloration near the turbocharger area.

Subsequent examination of the engine revealed soot and a darkening of the area below and behind the fuel injector system near the turbocharger. The top engine cowling, which exhibited paint bubbling and discoloration from exposure to intense heat, was placed over the top of the engine and the damage was consistent with the area above the fuel injector system.

The fuel system was then pressurized with 40psi of air and the sound of escaping air was heard in and around the mixture control arm of the fuel injector system. A mixture of water/soap was sprayed on the area where air was heard, and bubbles were immediately observed. Other areas of the engine were also sprayed with the water/soap mixture and no other signs of leaks were observed. The area where the leak was observed was consistent with fuel dripping and being blown onto the hot turbocharger in flight.

The fuel injector system was removed, and blue staining was observed in and around the mixture arm. A pressure check of the exhaust system was also conducted. No leaks were observed at any welds or joints.

A review of the engine logbook entries did not reveal evidence of any recent maintenance or repair on the fuel injection system. An annual inspection was completed on June 2, 2017 and a 100-hr inspection was completed on September 13, 2017.