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the line of sight reference can be held on the
pylon by gradually increasing the bank. The reference
line should appear to pivot on the pylon. As the airplane
heads into the wind, the groundspeed
decreases; consequently, the pivotal altitude is lower
and the airplane must descend to hold the reference
line on the pylon. As the turn progresses on the
upwind side of the pylon, the wind becomes more of
a crosswind. Since a constant distance from the pylon
is not required on this maneuver, no correction to
counteract drifting should be applied during the turns.
If the reference line appears to move ahead of the
pylon, the pilot should increase altitude. If the reference
line appears to move behind the pylon, the pilot
should decrease altitude. Varying rudder pressure to
yaw the airplane and force the wing and reference
line forward or backward to the pylon is a dangerous
technique and must not be attempted.
As the airplane turns toward a downwind heading,
the rollout from the turn should be started to allow
the airplane to proceed diagonally to a point on the
downwind side of the second pylon. The rollout
must be completed in the proper wind correction
angle to correct for wind drift, so that the airplane
will arrive at a point downwind from the second
pylon the same distance it was from the first pylon
at the beginning of the maneuver.
Upon reaching that point, a turn is started in the opposite
direction by lowering the upwind wing to again place
the pilot’s line of sight reference on the pylon. The turn
Too High
Pivotal Altitude
Too Low
Figure 6-13. Effect of different altitudes on pivotal altitude.
Ch 06.qxd 5/10/04 5:55 AM Page 6-15
6-16
is then continued just as in the turn around the first
pylon but in the opposite direction.
With prompt correction, and a very fine control
touch, it should be possible to hold the projection of
the reference line directly on the pylon even in a stiff
wind. Corrections for temporary variations, such as
those caused by gusts or inattention, may be made by
shallowing the bank to fly relatively straight to bring
forward a lagging wing, or by steepening the bank
temporarily to turn back a wing which has crept
ahead. With practice, these corrections will become
so slight as to be barely noticeable. These variations
are apparent from the movement of the wingtips long
before they are discernable on the altimeter.
Pylon eights are performed at bank angles ranging
from shallow to steep. [Figure 6-14] The student
should understand that the bank chosen will not alter
the pivotal altitude. As proficiency is gained, the
instructor should increase the complexity of the
maneuver by directing the student to enter at a distance
from the pylon that will result in a specific bank angle
at the steepest point in the pylon turn.
The most common error in attempting to hold a pylon
is incorrect use of the rudder. When the projection of
the reference line moves forward with respect to the
pylon, many pilots will tend to press the inside rudder
to yaw the wing backward. When the reference line
moves behind the pylon, they will press the outside
rudder to yaw the wing forward. The rudder is to be
used only as a coordination control.
Other common errors in the performance of eights-onpylons
(pylon eights) are:
• Failure to adequately clear the area.
• Skidding or slipping in turns (whether trying to
hold the pylon with rudder or not).
• Excessive gain or loss of altitude.
• Over concentration on the pylon and failure to
observe traffic.
• Poor choice of pylons.
• Not entering the pylon turns into the wind.
• Failure to assume a heading when flying
between pylons that will compensate sufficiently
for drift.
• Failure to time the bank so that the turn entry is
completed with the pylon in position.
• Abrupt control usage.
• Inability to select pivotal altitude.
Pylon
Pivotal
Altitude
60° ° °
Figure 6-14. Bank angle vs. pivotal altitude.
Ch 06.qxd 5/7/04 7:35 AM Page 6-16
AIRPORT TRAFFIC
PATTERNS AND OPERATIONS
Just as roads and streets are needed in order to utilize
automobiles, airports or airstrips are needed to utilize
airplanes. Every flight begins and ends at an airport or
other suitable landing field. For that reason, it is
essential that the pilot learn the traffic rules, traffic
procedures, and traffic pattern layouts that may be in
use at various airports.
When an automobile is driven on congested city streets,
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