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side.
Since the airplane is turning from an upwind to a
downwind heading, the groundspeed will increase
and after turning 90°, the rate of closure with the road
will increase rapidly. Consequently, the angle of bank
and rate of turn must be progressively increased so
that the airplane will have turned 180° at the time it
reaches the road. Again, the rollout must be timed so
the airplane is in straight-and-level flight directly
over and perpendicular to the road.
Throughout the maneuver a constant altitude should
be maintained, and the bank should be changing
constantly to effect a true semicircular ground track.
Often there is a tendency to increase the bank too
rapidly during the initial part of the turn on the
upwind side, which will prevent the completion of
the 180° turn before re-crossing the road. This is
apparent when the turn is not completed in time for
the airplane to cross the road at a perpendicular
angle. To avoid this error, the pilot must visualize the
desired half circle ground track, and increase the
bank during the early part of this turn. During the latter
part of the turn, when approaching the road, the
pilot must judge the closure rate properly and
increase the bank accordingly, so as to cross the road
perpendicular to it just as the rollout is completed.
Common errors in the performance of S-turns across a
road are:
• Failure to adequately clear the area.
• Poor coordination.
• Gaining or losing altitude.
• Inability to visualize the half circle ground track.
• Poor timing in beginning and recovering from
turns.
• Faulty correction for drift.
• Inadequate visual lookout for other aircraft.
TURNS AROUND A POINT
Turns around a point, as a training maneuver, is a
logical extension of the principles involved in the
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performance of S-turns across a road. Its purposes as
a training maneuver are:
• To further perfect turning technique.
• To perfect the ability to subconsciously control
the airplane while dividing attention between the
flightpath and ground references.
• To teach the student that the radius of a turn is a
distance which is affected by the degree of bank
used when turning with relation to a definite
object.
• To develop a keen perception of altitude.
• To perfect the ability to correct for wind drift
while in turns.
In turns around a point, the airplane is flown in two or
more complete circles of uniform radii or distance
from a prominent ground reference point using a maximum
bank of approximately 45° while maintaining a
constant altitude.
The factors and principles of drift correction that are
involved in S-turns are also applicable in this maneuver.
As in other ground track maneuvers, a constant
radius around a point will, if any wind exists, require a
constantly changing angle of bank and angles of wind
correction. The closer the airplane is to a direct downwind
heading where the groundspeed is greatest, the
steeper the bank and the faster the rate of turn required
to establish the proper wind correction angle. The
more nearly it is to a direct upwind heading where the
groundspeed is least, the shallower the bank and the
slower the rate of turn required to establish the proper
wind correction angle. It follows, then, that throughout
the maneuver the bank and rate of turn must be
gradually varied in proportion to the groundspeed.
The point selected for turns around a point should
be prominent, easily distinguished by the pilot, and
yet small enough to present precise reference.
[Figure 6-6] Isolated trees, crossroads, or other similar
small landmarks are usually suitable.
To enter turns around a point, the airplane should be
flown on a downwind heading to one side of the
selected point at a distance equal to the desired radius
of turn. In a high-wing airplane, the distance from the
point must permit the pilot to see the point throughout
the maneuver even with the wing lowered in a bank. If
the radius is too large, the lowered wing will block the
pilot’s view of the point.
When any significant wind exists, it will be necessary to
roll into the initial bank at a rapid rate so that the steep-
Steepest
Bank
Shallowest
Bank
Steeper
Bank
Shallower
Bank
Upwind Half of Circle
Downwind Half of Circle
Figure 6-6.Turns around a point.
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6-9
est bank is attained abeam of the point when the airplane
　
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