On 24 February 2009, a Bombardier CRJ200 being operated by Air Nostrum on a scheduled domestic passenger flight from Madrid to Santander suffered a double engine failure during descent in day Visual Meteorological Conditions (VMC) but a successful double restart was achieved and the flight to destination was completed without further event. None of the 48 occupants were injured and there was no damage to the aircraft.
An Investigation was carried out by the Spanish CIAAIC. Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) data were available to the Investigation. It was noted that both flight crew were experienced on the aircraft type and that the aircraft commander had been acting a PF on the incident flight. As the aircraft passed FL200, both engines had stopped and, with the speed above the necessary minimum of 240 KIAS, a successful restart had been achieved within approximately a minute by the prompt selection of continuous ignition in accordance with the applicable memory Quick Reference Handbook (QRH) drill. In accordance with design, the Air Driven Generator (ADG) had deployed when the engines stopped and the reduced electrical status had temporarily removed much of the functionality from the First Officer’s panel.
Shortly after the engines had been restarted, a Captain who was on board in the passenger cabin entered the flight deck and, on the suggestion of this pilot, the operating flight crew had belatedly declared an emergency to ATC and were “given landing priority” at destination. The ‘deadheading’ Captain had remained in the flight deck until the completion of the flight.
Extensive investigation found that all aircraft systems had functioned normally during the incident flight and it was concluded that the action of the PF in taking both thrust levers below the Idle position at the lower end of the ‘Flight’ range after overriding the mechanical stops designed to prevent inadvertent action to this effect was the cause of the shutdown.
It was noted that:
- Some other aircraft types have a thrust control system which requires a second action in addition to thrust lever movement to achieve shutdown. It was confirmed that the design of the thrust control levers on the incident aircraft type complied will all applicable certification requirements.
- The in-flight double engine failure procedure does not include task sharing between the flight crew and such did not occur during the event.
It was determined the Probable Cause of the shutdown of the engines in flight was the “placing the engine thrust levers below flight idle in an attempt to reduce engine thrust below flight idle”
Three Safety Recommendations were made as a result of the Investigation as follows:
- that Air Nostrum modify the company operations manual to explicitly state that placing the thrust levers in any position below IDLE mark, between IDLE and SHUT OFF, could shut down the engines even before the SHUT OFF mark is reached. [REC 01/12]
- that Air Nostrum include as part of its emergency actions the need to report the number of people onboard the aircraft whenever an emergency is declared. This is so as to avoid additional communications or interruptions during situations that may require a high workload. [REC 02/12]
- that Air Nostrum modify its in-flight double engine failure emergency procedure so as to clearly define the task sharing and functions between the flight crew and allow for the efficient completion of the procedure and the restarting of the engines in flight. [REC 03/12]
The Final Report of the Investigation Report IN-005/2009 was approved for release on 3 May 2012.