20120909021669A

9/10/2012:Two asi's were dispatched to gcn to investigate an aircraft accident regarding an operators aircraft that reported an engine flameout while attempting and autorotation post maintenance inspection (manufacturers program 100HR).9/10/2012:arrived at operators maintenance facility at approximately 10:45 am. The NTSB iic had allowed the operator to remove the aircraft from the accident site and relocate it to their facility. The aircraft was in the operators maintenance hangar. The aircraft had been covered/wrapped with tarps prior to relocation. These covers had to be removed prior to initiating an investigation. During the course of the autorotation to the ground this aircraft received damage. The vertical fin, tail rotor gearbox, aft section of the tailboom and the tops of the finlets were removed. Also both main rotor blades had damage. In addition one of the pitch change links had been severed. While at the maintenance facility there were several aircraft elements/systems/ or components reviewed or investigated in attempt to validate an engine flameout.1) fuel sample taken from the aircraft fuel tank sump, no contaminants noted.2) fuel sample taken from the facet fuel filter, no contaminants noted.3) checked for fuel aft of facet filter(bleed aft of bypass valve with boost pumps on). No air in system noted, also fuel sample taken at this point, no contaminants noted.4) checked for fuel between fuel supply line at fuel nozzle. Boost pumps on/motoring engineno air in system noted, also fuel sample taken at this point, no contaminants noted.5) applied torque stripe to all engine fuel/air line "b" nut fittings. Checked tightness of fittings by hand, no loose fittings found.6) checked exhaust duct, nothing found in duct.7) checked engine inlet between inlet particle separator and 1st stage compressor wheel. No objects or damage found.8) checked fuel control rigging from throttle at collective through fuel control, no deficiencies noted.9) checked collective throttle to ensure positive lock at ground idle from 100%. Unable to move throttle from 100% beyond ground idle. A positive lock was achieved.10) removed airframe fuel tank filler cap to look for foreign objects in fuel cell. No objects found, also ran boost pumps, good fuel movement/flow was noted. Furthermore checked "b" nut fitting on fuel supply line from fuel cell to engine bay. This fitting was tight.11) removed facet fuel filter, inspected for contaminants (none found in bowl or filter element), also fuel sample taken.12) with the main rotor head & blades removed as well as the tail rotor driveshaft disconnected there was an effort to start the engine. The engine started normally and was first run at idle, then at 100% without a load due to removal of the rotor system. At the time of engine run a soapy solution was applied to the engine air (pc) lines checking for leaks. One leak was noted between the engine scroll and the pc filter. This line was tight when checked by hand earlier but reflected a leak when the solution was applied. There was no effect during the engine run. Prior to departing the operators maintenance facility the NTSB & engine manufacturer accident investigator were contacted/debriefed with the results of the above stated findings.9/11/2012:initiated contact between operator and engine manufacturer for engine to be shipped to a facility for further examination. The engine was removed from the airframe and delivered to manufacturers service center in Arizona. Currently there is a scheduled engine run (run as received) then a subsequent inspection if needed. The scheduled date for the above is 10/02/2012.10/2/2012:report from supporting ASI, post engine run: engine was tested from initial start through several simulated modes of flight. The engine performed as it should. No evidence was observed that may contribute to an engine flameout.