History of Flight
On July 14, 2009, at approximately 1000 Pacific daylight time, a Piper PA-46-310P (registration N330HT) made a forced landing following an in-flight fire near Westley, California. The aircraft was operated by the owner/pilot under 14 CFR Part 91. The flight was a local instructional flight that had departed Concord, California, about 0830. Visual meteorological conditions prevailed, and no flight plan was filed. The certificated commercial pilot with a certified flight instructor (CFI) certificate and the private pilot undergoing instruction were not injured. The airplane sustained substantial damage.
The CFI reported that during a biennial review flight with the owner, smoke entered the cockpit from the area of the copilot's rudder pedals. The pilots performed emergency procedures for an electrical fire, shutting down the electrical systems. The CFI tried to clear the smoke by opening window vents; the smoke subsided but did not stop. Without electrical power, the landing gear would not lower. The pilots briefly energized the system to lower the gear, but no response was observed, and they turned the system off again. Shortly after, the engine lost power, and the pilots descended. Attempts to restart the engine failed, and they focused on an off-airport landing. The smoke intensified, and the CFI left the copilot seat to search for the source, during which the private pilot saw a flickering light at the base of the rudder pedals, possibly flames. At about 1,000 feet msl, the CFI returned to assist with landing. The landing site was a plowed field; the touchdown was firm, and the nose wheel collapsed almost immediately. The pilots did not realize the main landing gear had lowered and locked until touchdown.
Aircraft Information
The airplane was a Piper Malibu PA-46-310P, serial number 46-8408010. Total airframe time at the last annual inspection was 3,700 hours, and at the time of the accident it was 3,733.9 hours. The aircraft was originally manufactured with a Teledyne Continental Motors (TCM) TSIO-520-BE engine, but in October 2002 it was modified per STC SA00280AT to install a TCM TSIO-550-C1B engine, serial number 802584. The engine logbook indicated installation on October 11, 2002, with a total time of 434.0 hours. At the last annual inspection, the engine had 1,360 hours total time and time since major overhaul.
Examination
The aircraft was recovered and transported to Plain Parts, Pleasant Grove, California. On July 30, 2009, investigators examined the airplane and engine. The engine showed no mechanical anomalies that would have precluded normal operation. Visual examination of the engine compartment revealed dark sooty deposits behind the rear engine cylinder baffles, on rear engine accessories, the firewall and its components, the top aft engine cowling, and in the nose landing gear wheel well area. Fire damage was found to fluid and air hoses, electrical wires, nose gear hydraulic lines, the forward baggage compartment floor and carpet, and the nose landing gear tire, steering boots, and fluid lines in the wheel well.
Examination of the firewall and exhaust system showed that the lower duct assembly attached to the bleed and ram air selector valve sustained heat and impact damage. The TCM 550 series engine uses an exhaust crossover pipe with a permanently attached stainless heat shield. The crossover pipe ran directly forward of and in line with the lower bleed air ducting. The TCM 520 series engine originally installed used the same crossover tube, with an aluminum heat shield (Piper P/N 84104-14) that sustained heat damage and partially melted. One of the two riveted attaching clamps had sheared, allowing the clamp to move inward.
The nose landing gear actuator's upper housing attaches to the lower engine mount assembly, directly below the bleed air valve ducting damaged by the exhaust crossover tube. The hydraulic down line attaches to the top side of the upper housing and is positioned under the same ducting. Hydraulic fluid residue was present on the actuator housing. The nose gear actuator flexible hose assembly had extensive fire damage. The hose remained attached at both fittings, but the socket fitting on the actuator end showed a crack running its entire length. The hose could be pulled out by hand. Manufacturer's identification indicated the hose assembly was manufactured in the third quarter of 1991. The PA-46-310P maintenance manual for the landing gear group states to replace flexible hoses as required, but no later than 1,000 hours or eight years, and at engine overhaul. No logbook entry was found indicating the hose assembly had ever been replaced.