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hold altitude changes temporarily (about 2 seconds).
This would be like applying flaps on an airplane if no
elevator control was available.
While trying to maintain a constant altitude, especially
when close to the ground, you can fly with about onethird
flare. By holding a small flare, if you encounter
downdrafts, you can immediately add a large portion
of flare to lift you back to the desired altitude. If the
PPC begins to climb, then you can reduce the amount
of the flare to return to the desired altitude, until you
can adjust your throttle position again.
Common errors in the performance of straight-andlevel
flight are:
• Attempting to use improper reference points on
the aircraft to establish attitude.
• Forgetting the location of preselected reference
points on subsequent flights.
• Attempting to establish or correct aircraft
attitude using flight instruments rather than
outside visual reference.
• Overcontrol and lack of feel.
• Improper scanning and/or devoting insufficient
time to outside visual reference.
• Fixation on the nose (pitch attitude) reference
point.
• Unnecessary or inappropriate control inputs.
• Failure to make timely and measured control
inputs when deviations from straight-and-level
flight are detected.
• Inadequate attention to sensory inputs in
developing feel for the PPC.
Level Turns
A turn is made by banking the wing in the direction of
the desired turn. A specific angle of bank is selected
by the pilot, control pressures applied to achieve the
desired bank angle, and appropriate control pressures
exerted to maintain the desired bank angle once it is
established.
Both primary controls are used in close coordination
when making level turns. Their functions are as follows.
• The steering bars bank the wings and so
determine the rate of turn.
• The throttle determines vertical speed and must
be increased during a turn for the PPC to remain
level. The greater the degree of turn, the greater
the throttle/thrust required to remain level; this
is similar to an airplane and weight-shift control
aircraft.
ing power). While foot controls do have an effect on
altitude, they are not typically used as a control for
flying straight and level. A PPC must be capable of
maintaining altitude to tolerances using the controls
as designed.
Anytime the wing is banked, even very slightly, the
aircraft will turn. In a PPC the pilot has no useful
reference to measure bank angle like an airplane or
weight shift control aircraft where the wing tips are
visible in relation to the horizon. The objective of
straight-and-level flight is to detect small deviations
from laterally level flight as soon as they occur, necessitating
only small corrections. Reference to the magnetic
compass or GPS, if so equipped, can be made
to note any change in direction; however, the visual
reference of a point on the horizon with a point on the
aircraft such as the front wheel or instrument panel
will typically be used for sport pilot training.
Continually observing the nose to align the heading
should be avoided. The pilot must spend more time
scanning for air traffic than focusing on heading. This
helps divert the pilot’s attention from the aircraft’s
nose, prevents a fixed stare, and automatically expands
the pilot’s area of vision by increasing the range
necessary for the pilot’s vision to cover.
Straight-and-level flight requires almost no application
of control pressures if the aircraft is properly
trimmed to fly straight and the air is smooth. Some
PPCs will have a directional trim control which adjusts
the tension in a control line to make it fly straight.
Each PPC manufacturer has a unique design for their
particular aircraft. The pilot must not form the habit
of constantly moving the controls unnecessarily. You
must learn to recognize when corrections are necessary,
and then make a measured response. Tolerances
necessary for passing the PPC practical test are ±10
degrees heading and ±100 feet altitude. Students may
initially start to make corrections when tolerances are
exceeded but should strive to initiate a correction before
the tolerances are exceeded, such as starting correction
before the tolerance is ±5 degreees heading
and ±50 feet altitude.
Since the PPC does not have an elevator to control the
pitch, immediate minor adjustments should be made
while flying close to the ground. In flying a low approach
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Powered Parachute Flying Handbook动力伞飞行手册(54)
