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an emergency landing without undue hazard to persons or
property on the surface.” This allows long fi nal approaches
“with power when necessary,” but overall, it is important to
be no lower than an altitude from which you can glide to a safe
landing area. For the purposes of this approach-and-landing
discussion, it is assumed that there are no safe landing areas
other than the runway.
It should be noted that the power is above idle for some
landing situations, such as:
• Students fi rst learning to land; a slower rate of descent
is the result of higher power settings. In this case, the
landings would be done with a target farther down the
runway so a safe landing could always be made with
engine failure.
• Shallower descent angle if directed by air traffi c control
(ATC), or a longer fi nal approach is required.
• High winds and/or turbulent conditions requiring a
higher energy level.
For landings where throttle is required, the foot throttle is
typically used so the hands can stay on the control bar while
approaching the ground for this critical phase of fl ight.
However, the hand/cruise throttle may be set above idle for
specifi c situations as required by the pilot. Higher power
settings for approaches and landings are discussed later in
this chapter.
Base Leg
The placement of the base leg is one of the more important
judgments made by the pilot in any landing approach.
[Figure 11-1] The pilot must accurately judge the altitude
and distance from which the descent results in landing at
the desired point.
The base leg should be started at a point where the power
can be brought back to idle and the WSC aircraft can glide to
the landing spot at the approach speed recommended by the
manufacturer. The intended landing point should not be at the
end of the runway on a threshold or numbers, but beyond at
the landing lines. [Figure 11-2] This provides some margin
if the landing is shorter than anticipated. For smaller runways
that do not have these markings, establish an appropriate
11-3
Aiming Point for Landings
Figure 11-2. Typical landing position on runway.
36
18
Figure 11-1. Base leg and final approach.
landing point beyond the start of the runway, allowing plenty
of room for the after-landing roll. At much larger airports, the
landing can be done farther down the runway or at a location
where the pilot can taxi off the runway and not delay other
air traffi c behind the aircraft.
After turning onto the base leg, the pilot should continue
the descent with reduced power and approach airspeed as
recommended by the manufacturer. As discussed in Chapter
7, Takeoff and Departure, this speed is at least 1.3 times the
stall speed. Landing trim should be adjusted according to
manufacturer specifi cations (if equipped).
Drift correction should be established and maintained to follow
a ground track perpendicular to the extension of the centerline
of the runway on which the landing is to be made. Since the
fi nal approach and landing are normally made into the wind,
there may be a crosswind during the base leg. The aircraft must
be angled suffi ciently into the wind to prevent drifting farther
away from the intended landing point.
The base leg should be continued to the point where a
medium- to shallow-banked turn aligns the aircraft’s path
directly with the centerline of the landing runway. This
descending turn should be completed at a safe altitude that is
dependent upon the height of the terrain and any obstructions
along the ground track. The turn to the fi nal approach should
also be suffi ciently above the airport elevation to permit a
11-4
Figure 11-4. Turning from base onto final.
Runway
Figure 11-3. On base preparing to turn onto final.
Figure 11-5. Lining up on the runway centerline and maintaining
position.
fi nal approach long enough for the pilot to accurately estimate
the resultant point of touchdown, while maintaining the
proper approach airspeed. This requires careful planning
for the starting point and radius of the turn. [Figure 11-3]
Normally, it is recommended that the angle of bank not
exceed a medium bank because the steeper the angle of bank,
the higher the airspeed at which the aircraft stalls. Since the
base-to-fi nal turn is made at a relatively low altitude, it is
important that a stall not occur at this point. If an extremely
steep bank is needed to prevent overshooting the proper fi nal
approach path, it is advisable to discontinue the approach, go
around, and plan to start the turn earlier on the next approach
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Weight-Shift Control Aircraft Flying Handbook(114)