Narrative:

While conducting aircraft recurrent training/evaluation; at completion of 'fadec failure' maneuver evaluation on ground prior to reducing collective to flat pitch; rolled the #2 engine (affected engine) to ground idle. This action reduces the opportunity for the affected engine to drive the affected N2 and nr (rotor RPM) to an overspeed condition. Aviator continued to roll the affected engine twist grip/throttle; bypassing the idle stop and the engine was inadvertently shut down. We went through a complete shutdown of the affected engine in preparation for a restart. Switchology was all reset and an engine restart was attempted. Because of the resetting of switches which included the affected engine 'fadec' switch; the cad (caution advisory display) indicated a 'degrade' caution light on the operating engine (#1 engine). Because of this; I believe; we could not restart the affected engine (#2 engine). We continued to sit on the runway and took our time evaluating the situation and switches to ensure we were acting correctly. After a second try at starting the engine without success; I determined that I needed to shut the aircraft down completely to allow the 'fadec' system logic to completely reset. Because of our decision to completely shut down the aircraft for a restart and our location on the primary runway; I decided to move the aircraft under single engine power to the adjoining ramp approximately 50 ft away from our location on the primary and only runway. Additional circumstances affecting my decision to fly this aircraft under single engine power were; the airport is an uncontrolled airfield; there had been other aircraft in the vicinity using the runway during our training period; we were in dark/night conditions with little illumination from the moon or other lighting; and shutting down the aircraft would have meant being completely dark with battery off; thus no radio or aircraft lighting available to identify ourselves on the runway. The aircraft was down to less than 60 gallons of fuel in the main tank and the feeder tanks had their respective 15 gallons each; thus the aircraft operating weight at time of incident was well within the capability of the aircraft to operate single engine without exceeding any limitations.

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Original NASA ASRS Text

Title: EC135 Check Airman reports an inadvertent engine shutdown while on the runway of an uncontrolled airport at night. A complete electrical shut down is determined to be necessary to restart the engine but is deemed to risky on the runway. The helicopter is single engine air taxied to clear the runway and perform the shutdown and restart.

Narrative: While conducting aircraft recurrent training/evaluation; at completion of 'FADEC Failure' maneuver evaluation on ground prior to reducing collective to flat pitch; rolled the #2 engine (affected engine) to ground idle. This action reduces the opportunity for the affected engine to drive the affected N2 and NR (rotor RPM) to an overspeed condition. Aviator continued to roll the affected engine twist grip/throttle; bypassing the idle stop and the engine was inadvertently shut down. We went through a complete shutdown of the affected engine in preparation for a restart. Switchology was all reset and an engine restart was attempted. Because of the resetting of switches which included the affected engine 'FADEC' switch; the CAD (Caution Advisory Display) indicated a 'DEGRADE' caution light on the operating engine (#1 Engine). Because of this; I believe; we could not restart the affected engine (#2 engine). We continued to sit on the runway and took our time evaluating the situation and switches to ensure we were acting correctly. After a second try at starting the engine without success; I determined that I needed to shut the aircraft down completely to allow the 'FADEC' system logic to completely reset. Because of our decision to completely shut down the aircraft for a restart and our location on the primary runway; I decided to move the aircraft under single engine power to the adjoining ramp approximately 50 FT away from our location on the primary and only runway. Additional circumstances affecting my decision to fly this aircraft under single engine power were; the airport is an uncontrolled airfield; there had been other aircraft in the vicinity using the runway during our training period; we were in DARK/NIGHT conditions with little illumination from the moon or other lighting; and shutting down the aircraft would have meant being completely dark with battery off; thus no radio or aircraft lighting available to identify ourselves on the runway. The aircraft was down to less than 60 gallons of fuel in the main tank and the feeder tanks had their respective 15 gallons each; thus the aircraft operating weight at time of incident was well within the capability of the aircraft to operate single engine without exceeding any limitations.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.