On 13 February 2000 a Beech 1900D Airliner, VH-NTL, was on a local training flight. The pilot in command simulated a failure of the left engine shortly after takeoff by retarding the left power lever to the 'FLIGHT IDLE' position. The handling pilot applied full right rudder and right aileron to counter the resultant yaw to the left, but the yaw continued until power was restored to the left engine to regain directional control. In the 21 seconds following takeoff, the aircraft did not climb above 160 ft above ground level, and at one stage had descended to 108 ft.
The aircraft was then climbed to a height of 2,000 ft where the pilot in command simulated another failure of the left engine by retarding its power lever to the 'FLIGHT IDLE' power setting. The aircraft again lost controllability. Power was restored to the left engine, and the aircraft landed without further incident.
There was no evidence that any aircraft or systems malfunctions contributed to the controllability problems experienced by the crew during the occurrence flight.
Since 1992, it was the practice of the operator's check pilots to simulate one-engine inoperative by retarding the power lever of the 'failed' engine to 'FLIGHT IDLE'. That was contrary to the procedure prescribed in the Federal Aviation Authority-approved Beech 1900D Airplane Flight Manual, and also to that specified in the operator's Civil Aviation Safety Authority-approved Training and Checking Manual. Reducing power to 'FLIGHT IDLE' also had the effect of simulating a simultaneous failure of the engine and its propeller auto-feather system. The simulation of simultaneous inflight failures was contrary to the provisions of the CASA-approved Training and Checking Manual. During each of the simulated one-engine inoperative sequences, control of the aircraft was not regained until the power on the 'failed' engine was advanced to the manufacturer's prescribed one-engine inoperative thrust power setting.
The operator's training and checking organisation and its check pilots were aware that the likely consequences of simulating an engine failure by retarding its power to less than zero thrust were reduced aircraft climb performance and increased air minimum control speed (VMCA). They were also aware that risk increased when inflight training exercises involved the simulation of multiple failures. The prescribed procedures were therefore necessary defences to minimise those risks. The circumvention of those defences significantly increased the risks associated with the operator's training and checking procedures, and was a safety-significant concern. This occurrence demonstrated the potentially serious consequences of degraded aircraft performance by setting 'FLIGHT IDLE' to simulate one-engine inoperative. The practice has the potential to jeopardise the safety of flight and should be strongly discouraged.
The ATSB's investigation established that the failure to achieve predicted performance during take-off and subsequent climb was the result of an incorrect procedure. As a result of this serious occurrence, the ATSB recommended that the Civil Aviation Safety Authority (CASA) publish information for the guidance of operators and pilots regarding the correct procedures for simulating engine failures in turbo-propeller aircraft. CASA advised that it will publish an amendment to Civil Aviation Advisory Publication 5.23-1(0) to highlight appropriate engine-out training procedures in turbo-propeller aircraft. CASA also advised that it would ensure that operators' manuals contained appropriate procedures for the conduct of multi-engine training,and that it would draw attention to those procedures during forthcoming safety promotion activities. The operator advised that it had instructed its check pilots that an engine's power lever must not be retarded below the zero thrust torque setting when simulating an engine failure on takeoff, and that those simulations were not be carried out until the aircraft had reached 250 ft above ground level.
|Date:||13 February 2000||Investigation status:||Completed|
|Time:||1215 hours ESuT|
|State:||New South Wales||Occurrence type:||Control - Other|
|Release date:||21 December 2001||Occurrence class:||Operational|
|Report status:||Final||Occurrence category:||Serious Incident|
|Highest injury level:||None|
|Aircraft manufacturer||Beech Aircraft Corp|
|Type of operation||Air Transport Low Capacity|
|Damage to aircraft||Nil|
|Departure point||Williamtown, NSW|
|Departure time||1215 hours ESuT|
|Role||Class of licence||Hours on type||Hours total|