#4a Engine Failure during Takeoff
To develop the ability to recognize and safely control the aircraft following the failure of an engine during takeoff.
This exercise is not a flight test item, but is conducted during the course of flight training for the rating.
The takeoff roll is an extremely vulnerable period for the occupants of a multi-engine aircraft. During this phase—all of it conducted at speeds below Vmc—there is insufficient airflow over the control surface to even come close to countering the effect of asymmetric thrust that would result if an engine should fail. The game is over. Without immediate abortive actions by the pilot—and I do mean immediate—the aircraft will veer out of control, resulting in a potentially explosive crash. The only factor working in the favour of the pilot is that the action required to abort the takeoff, once an engine fails, is simple—rapidly close the throttle on the engine that is still developing potentially lethal maximum power.1 We must not kid ourselves, however; while the remedial action is simple enough, the successful completion of the action requires that every takeoff roll be conducted with complete concentration and situational awareness. This message will be effectively brought home by this exercise.
To undertake this exercise, prior arrangements are made with the Tower unit to conduct “simulated engine failures during takeoff.” All normal pre-takeoff checks are completed, including runway checks, and the aircraft will be cleared for “high speed taxiing on the runway.” Once in position, the normal takeoff procedures are followed, but shortly after “maximum power” is set, and the aircraft has started to pick-up speed down the runway, the instructor will retard one of the throttles. Things will happen very quickly now, as the aircraft will immediately begin to yaw in the direction of the failed engine. The job of the student is to recognize this, and to simultaneously retard the throttle of the remaining (good) engine. Until this is done the aircraft is, quite literally, out of control—and it really appears quite dramatic. Immediate response is critical, but as soon as both throttles are brought back to idle settings, the aircraft becomes passive again, and is easily controlled as it rolls—now decelerating—down the runway.
The management and solution of an engine failure during a takeoff roll is simple and effective, but the important message learned from this exercise is that the pilot conducting the takeoff roll must be absolutely attentive to any directional deviation of the aircraft. The pilot’s hand must always be on the throttle and at the ready for a rejected takeoff—only a delay of one second (quite literally) could spell disaster.
The exercise will be repeated a couple of times for the purpose of familiarisation.
Remember to be gentle but firm with the aircraft. When the aircraft appears to begin the directional deviation after the failure has been simulated, begin immediately to input corrective rudder. As both throttles are retarded to the stops, additional re-corrections will be required, but try not to over-torque the rudder pedals—simple redirect the aircraft smoothly back to the centreline. Go easy on the brakes as well—so long as the remaining runway distance does not become an immediate issue, allow the aircraft to bleed off momentum by coasting.
Care and attention has to be given to the handling of the throttles during this exercise, as both the Instructor and the student will have to access the throttles in quick succession. When you have advanced the throttles
to their maximum forward position for maximum power, hold your hand clear but close, as indicated on the right, giving the Instructor room to reduce one of the throttles to idle. As soon as you recognized the asymmetric thrust, respond quickly by closing the throttle that remains open. Even the slightest delay will cause the Instructor to intervene.
1. You don’t care at this point which engine is causing the problem—pull both throttles back to idle