If an engine should fail during the takeoff roll before becoming airborne, it is advisable to close both throttles immediately and bring the airplane to a stop. The same procedure is recommended if after becoming airborne an engine should fail prior to having reached the single engine best rate of climb speed (Vyse). An immediate landing is usually inevitable because of the altitude loss required to increase the speed to Vyse.
The pilot must have determined before takeoff what altitude, airspeed, and airplane configuration must exist to permit the flight to continue in event of an engine failure - the pilot also should be ready to accept the fact that if engine failure occurs before these required factors are established, both throttles must be closed and the situation treated the same as engine failure on a single engine airplane. If it has been predetermined that the engine out rate of climb under existing circumstances will be at least 50 feet per minute at 1,000 feet above the airport, and that at least the engine out best angle of climb speed has been attained, the pilot may decide to continue the takeoff.
If the airspeed is below the engine out best angle of climb speed (Vxse) and the landing gear has not been retracted, the takeoff should be abandoned immediately.
If the engine out best angle of climb speed (Vxse) has
been obtained and the landing gear is in the retract cycle, the pilot should
climb at the engine out best angle of climb speed (Vxse) to clear any obstructions,
and thereafter stabilize the airspeed at the engine out best rate of climb
speed (Vyse) while retracting the landing gear and flaps and resetting
all appropriate systems.
When the decision is made to continue flight, the single engine best rate of climb speed should be attained and maintained (Fig. 16-13). Even if altitude cannot be maintained, it is best to continue to hold that speed because it would result in the slowest rate of descent and provide the most time for executing the emergency landing. After the decision is made to continue flight and a positive rate of climb is attained, the landing gear should be retracted as soon as practical.
If the airplane is just barely able to maintain altitude and airspeed, a turn requiring a bank greater than approximately 15 degrees should not be attempted. When such a turn is made under these conditions, both lift and airspeed will decrease. Consequently, it is advisable to continue straight ahead whenever possible, until reaching a safe maneuvering altitude. At that time a steeper bank may be made safely - and in either direction. There is nothing wrong with banking toward a "dead" engine if a safe speed and zero sideslip are maintained.
When an engine fails after becoming airborne, the pilot should hold heading with rudder and simultaneously roll into a bank of at least 5 degrees toward the operating engine. In this attitude the airplane will tend to turn toward the operating engine, but at the same time, the asymmetrical power resulting from the engine failure will tend to turn the airplane toward the "dead" engine. The result is a partial balance of those tendencies and provides for an increase in airplane performance as well as easier directional control.
NOTE: In this situation the ball in the turn and bank indicator will be approximately one ball width off center toward the good engine.
The best way to identify the inoperative engine is to note the direction of yaw and the rudder pressure required to maintain heading. To counteract the asymmetrical thrust, extra rudder pressure will have to be exerted on the operating engine side. To aid in identifying the failed engine, some pilots use the expressions "Best Foot Forward," or "Dead Foot Dead Engine." Never rely on tachometer or manifold pressure readings to determine which engine has failed. After power has been lost on an engine, the tachometer will often indicate the correct r.p.m. and the manifold pressure gauge will indicate the approximate atmospheric pressure or above.
Experience has shown that the biggest problem is not in identifying the inoperative engine, but rather in the pilot's actions after the inoperative engine has been identified. In other words, a pilot may identify the "dead" engine and then attempt to shut down the wrong one - resulting in no power at all. To avoid this mistake, the pilot should verify that the dead engine has been identified by retarding the throttle of the suspected engine before shutting it down.
When demonstrating or practicing procedures for engine failure on takeoff, the feathering of the propeller and securing of the engine should be simulated rather than actually performed, so that the engine may be available for immediate use if needed; but all other settings should be made just as in an actual power failure.
In all cases, the airplane manufacturer's recommended procedure for single engine operation should be followed. The general procedure listed below is not intended to replace or conflict with any procedure established by the manufacturer of any airplane. It can be used effectively for general training purposes and to emphasize the importance of Vyse. It should be noted that this procedure is concerned with an engine failure on a takeoff where obstacle clearance is not critical. If the decision is made to continue flight after an engine failure during the takeoff climb, the pilot should maintain directional control at all times and:
1. Maintain Vyse.
2. Check that all mixture controls, prop controls, and throttles (in that order) are at maximum permissible power settings.
3. Maintain Vyse.
4. Check that the flaps and landing gear have been retracted.
5. Maintain Vyse.
6. Decide which engine is inoperative (dead).
7. Maintain Vyse.
8. Raise the wing on the suspected "dead" engine side at least 5 degrees.
9. Maintain Vyse.
10. Verify the "dead" engine by retarding the throttle of the suspected engine. (If there is no change in rudder forces, then that is the inoperative engine.)
11. Maintain Vyse.
12. Feather the prop on the "dead" engine (verified by the retarded throttle).
13. Maintain Vyse.
14. Declare an emergency if operating from a tower controlled airport. Advise the tower of your intentions.
15. Maintain Vyse.