|CHAPTER 13. Abnormal and Emergency Procedures
Engine Failure After Takeoff
As discussed earlier in Chapter 7, Takeoff and Departure Climbs, proper takeoff technique provides lower pitch angles during the initial climb to provide the slowest possible descent rate for an engine failure after takeoff. The pitch angle and altitude available for engine failure at takeoff are the controlling factors in the successful accomplishment of an emergency landing. If an actual engine failure should occur immediately after takeoff and before a safe maneuvering altitude is attained, it is usually inadvisable to attempt to turn back to the takeoff fi eld. Instead, it is safer to establish the proper glide attitude immediately, and select a fi eld directly ahead or slightly to either side of the takeoff path.
The decision to continue straight ahead is often diffi cult to make unless the problems involved in attempting to turn back are seriously considered. First, the takeoff was probably made into the wind. To return to the takeoff fi eld, a downwind turn must be made. This increases the groundspeed and rushes the pilot even more in the performance of procedures and in planning the landing approach. Second, the aircraft loses considerable altitude during the turn and might still be in a bank when the ground is contacted, resulting in cartwheeling (a catastrophe for the occupants, as well as the aircraft). After turning downwind, the apparent increase in groundspeed could mislead the pilot into a premature attempt to slow the aircraft to a stall. Finally, it is more than one 180° turn. For example, it is fi rst a 225° turn in one direction, then another 45° turn in the other direction, totaling 310° of turn. [Figure 13-6]
On the other hand, continuing straight ahead or making a slight turn allows the pilot more time to establish a safe landing attitude. The landing can be made as slowly as desired, but more importantly, the aircraft can be landed while under control.
At airports where the runways are much longer than needed, there is typically ample runway to make a straight ahead landing. If a tight pattern is being used and the crosswind leg is started at the end of the runway, turning back the additional 90° to the runway could be the best option, depending on the suitability of landing areas straight ahead.
Depending on the specific design of the WSC aircraft considering weight, wing, and carriage, this maneuver can be performed with no reaction time and as low as 250 to 500 feet AGL. However, the pilot should determine the minimum altitude that such a maneuver would require of a particular aircraft. Experimentation at a much higher, safe altitude, 700 feet AGL as an example, should give the pilot an approximation of height lost in a descending 225° and 45° turn at idle power. Starting high above the ground at low bank angles and monitoring the altitude loss while doing the required turns to line back up on the runway provides a good reference. Finding the best bank angle to perform the required turns for this maneuver with minimum altitude loss is key to optimizing this maneuver and developing a habit if this maneuver is needed in a real emergency.
By adding a safety factor of about 30 percent to account for reaction time and no thrust from the propeller, the pilot should arrive at a practical decision height. The ability to make these turns does not necessarily mean that the departure runway can be reached in a power-off glide; this depends on the wind, the distance traveled during the climb, the height reached, and the glide distance of the aircraft without power.
This is a highly advanced maneuver with turns close to the ground. This should be practiced well into the training program with the instructor. For example, consider an aircraft which has taken off and climbed to an altitude of 350 feet AGL when the engine fails. After a typical 4-second reaction time, the pilot pulls down the nose, maintains control of the aircraft, and elects to turn back to the runway, losing 50 feet. [Figure 13-6, A to B] The pilot performs the 225° turn and loses 300 feet. [Figure 13-6, B to C] The pilot must glide back to the runway, losing another 50 feet. [Figure 13-6, C to D] The pilot must turn another 45° to head the aircraft toward the runway, losing another 50 feet. [Figure 13-6, D to E] By this time the total change in direction is 310°, the aircraft will have descended 450 feet, placing it 100 feet below the runway.
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