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13-9
45° Turn
225° Turn
A
B
C
D
E
Figure 13-6. Amount of turn required to land back on the takeoff
runway.
large bodies of water, fl otation devices, extra water, and a
water purifi er would be added to the basic survival gear. If
in desert conditions, bring a lot of water and hats for shade.
In situations of extreme temperature changes, add both sun
shading and layered clothing to the gear as appropriate.
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
13-10
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
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Weight-Shift Control Aircraft Flying Handbook(149)