What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) On September 24, 2000, temsco helicopters inc. experienced an uncontained in-flight engine failure of a Eurocopter AS-350-B3 during an instructional flight. A successful autorotation was accomplished with no injuries to the two pilots on board. During the event substantial damage did occur to the aircraft. The flight was initiated as a company training flight and the failure occurred during a practice autorotation. When the flying pilot initiated the autorotation, he inadvertently pushed the "bi-stable" slide switch on the pilot side collective twist grip. Actuation of this switch allows operation in the augmented fuel flow range. This range of operation is for emergency use in case of fadec (full authority digital engine control) malfunction. In this case the inadvertent operation of the emergency mode resulted in the overspeed and subsequent uncontained failure of the engine and loss of tail rotor drive. The instructor pilot took control and managed to autorotate to a hard landing that damaged the tail boom at the fuselage attach point.
As the FAA filed it
(-23) ON SEPTEMBER 24, 2000, TEMSCO HELICOPTERS INC. EXPERIENCED AN UNCONTAINED IN-FLIGHT ENGINE FAILURE OF A EUROCOPTER AS-350-B3 DURING AN INSTRUCTIONAL FLIGHT. A SUCCESSFUL AUTOROTATION WAS ACCOMPLISHED WITH NO INJURIES TO THE TWO PILOTS ON BOARD. DURING THE EVENT SUBSTANTIAL DAMAGE DID OCCUR TO THE AIRCRAFT. THE FLIGHT WAS INITIATED AS A COMPANY TRAINING FLIGHT AND THE FAILURE OCCURRED DURING A PRACTICE AUTOROTATION. WHEN THE FLYING PILOT INITIATED THE AUTOROTATION, HE INADVERTENTLY PUSHED THE "BI-STABLE" SLIDE SWITCH ON THE PILOT SIDE COLLECTIVE TWIST GRIP. ACTUATION OF THIS SWITCH ALLOWS OPERATION IN THE AUGMENTED FUEL FLOW RANGE. THIS RANGE OF OPERATION IS FOR EMERGENCY USE IN CASE OF FADEC (FULL AUTHORITY DIGITAL ENGINE CONTROL) MALFUNCTION. IN THIS CASE THE INADVERTENT OPERATION OF THE EMERGENCY MODE RESULTED IN THE OVERSPEED AND SUBSEQUENT UNCONTAINED FAILURE OF THE ENGINE AND LOSS OF TAIL ROTOR DRIVE. THE INSTRUCTOR PILOT TOOK CONTROL AND MANAGED TO AUTOROTATE TO A HARD LANDING THAT DAMAGED THE TAIL BOOM AT THE FUSELAGE ATTACH POINT.
Other reports on N405AE · 1
Matched to the same aircraft by N-number and date.