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selecting a road, railroad, or other ground reference that forms
a straight line parallel to the wind. Fly into the wind directly
over and along the line and then make a turn with a constant
medium angle of bank for 360° of turn. [Figure 9-3] The
aircraft returns to a point directly over the line but slightly
downwind from the starting point, the amount depending on
the wind velocity and the time required to complete the turn.
The path over the ground is an elongated circle, although in
reference to the air it is a perfect circle. Straight fl ight during
the upwind segment after completion of the turn is necessary
to bring the aircraft back to the starting position.
A similar 360° turn may be started at a specifi c point over the
reference line, with the aircraft headed directly downwind.
In this demonstration, the effect of wind during the constant
banked turn drifts the aircraft to a point where the line is
re-intercepted, but the 360° turn is completed at a point
downwind from the starting point.
Another reference line which lies directly crosswind may be
selected and the same procedure repeated. If wind drift is not
corrected, the aircraft is headed in the original direction at
the completion of the 360° turn, but has drifted away from
the line a distance dependent on the amount of wind.
From these demonstrations, it can be seen where and why
it is necessary to increase or decrease the angle of bank and
the rate of turn to achieve a desired track over the ground.
The principles and techniques involved can be practiced and
evaluated by the performance of the ground track maneuvers
discussed in this chapter.
Rectangular Course
Normally, the fi rst ground reference maneuver introduced
to the pilot is the rectangular course. Reference Figure 9-4
throughout this rectangular course section. The rectangular
course is a training maneuver in which the ground track
of the aircraft is equidistant from all sides of a selected
rectangular area on the ground. The maneuver simulates the
conditions encountered in an airport traffi c pattern. While
performing the maneuver, the altitude and airspeed should
be held constant.
The maneuver assists the student pilot in perfecting:
• Practical application of the turn.
9-5
Wind
Track with no wind correction
Track with no wind correction
Base Crosswind
Downwind
Upwind
No wind correction
Turn more than 90°
Complete turn at boundary
Start turn
at boundary
Exit
Turn into wind
Complete turn at boundary No wind correction Start turn at boundary
Start turn
at boundary
Turn into wind
Complete turn at boundary
roll out with wind
correction established
Turn more than 90°
Start turn at boundary
Turn less than 90°
Enter 45° to downwind
Turn less than 90°
Complete turn at boundary
roll out with wind
correction established
Figure 9-4. Rectangular course.
Start and finish
No wind
Wind Wind
Wind
Figure 9-3. Effect of wind during turns.
9-6
• Division of attention between the fl ightpath, ground
objects, and the handling of the aircraft.
• Timing of the start of a turn so that the turn is fully
established at a defi nite point over the ground.
• Timing of the recovery from a turn so that a defi nite
ground track is maintained.
• Establishing a ground track and determining the
appropriate “crab” angle.
As for other ground track maneuvers, one of the objectives
is to develop division of attention between the fl ightpath
and ground references while controlling the aircraft and
watching for other aircraft in the vicinity. Another objective
is to develop recognition of drift toward or away from a
line parallel to the intended ground track. This is helpful in
recognizing drift toward or away from an airport runway
during the various legs of the airport traffi c pattern.
For this maneuver, a square or rectangular fi eld (bound on
four sides by section lines or roads that are approximately
one-half mile in length) should be selected away from other
air traffi c. The aircraft should be fl own parallel to and at a
uniform distance just to the outside of the fi eld boundaries,
not quite above the boundaries so that the fl ightpath may be
easily observed from either seat by looking out the side of
the aircraft. The closer the track of the aircraft is to the fi eld
boundaries, the steeper the bank necessary at the turning
points. The distance of the ground track from the edges of
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Weight-Shift Control Aircraft Flying Handbook(104)
