曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
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 and easily distinguishable, yet small enough
to present a precise reference. Isolated trees,
crossroads, or other similar small landmarks are usually
suitable. The point should be in an area away from
communities, livestock, or groups of people on the
ground to prevent possible annoyance or hazard to
others. Since the maneuver is performed between 600
and 1,000 feet AGL, the area selected should also
afford an opportunity for a safe emergency landing in
the event it becomes necessary.
To enter turns around a point, fly the gyroplane on a
downwind heading to one side of the selected point at a
distance equal to the desired radius of turn. When any
significant wind exists, it is necessary to roll into the
initial bank at a rapid rate so that the steepest bank is
attained abeam the point when the gyroplane is headed
directly downwind. By entering the maneuver while
heading directly downwind, the steepest bank can be
attained immediately. Thus, if a bank of 40° is desired,
the initial bank is 40° if the gyroplane is at the correct
distance from the point. Thereafter, the bank is gradually
shallowed until the point is reached where the
gyroplane is headed directly upwind. At this point, the
bank is gradually steepened until the steepest bank is
again attained when heading downwind at the initial
point of entry.
Just as S-turns require that the gyroplane be turned into
the wind, in addition to varying the bank, so do turns
around a point. During the downwind half of the circle,
the gyroplane’s nose must be progressively turned
toward the inside of the circle; during the upwind half,
the nose must be progressively turned toward the outside.
The downwind half of the turn around the point
may be compared to the downwind side of the S-turn,
while the upwind half of the turn around a point may be
compared to the upwind side of the S-turn.
As you become experienced in performing turns
around a point and have a good understanding of the
effects of wind drift and varying of the bank angle and
wind correction angle, as required, entry into the
maneuver may be from any point. When entering this
maneuver at any point, the radius of the turn must be
carefully selected, taking into account the wind velocity
and groundspeed, so that an excessive bank is not
required later on to maintain the proper ground track.
COMMON ERRORS DURING GROUND
REFERENCE MANEUVERS
1. Faulty entry technique.
2. Poor planning, orientation, or division of
attention.
3. Uncoordinated flight control application.
4. Improper correction for wind drift.
UPPER HALF OF CIRCLE
DOWNWIND HALF OF CIRCLE
Shallowest
Bank
Steeper
Bank
Steepest
Bank
Shallower
Bank
WIND
F
Figure 20-12. Turns around a point.
20-12
5. An unsymmetrical ground track during S-turns
across a road.
6. Failure to maintain selected altitude or airspeed.
7. Selection of a ground reference where there is no
suitable emergency landing site.
FLIGHT AT SLOW AIRSPEEDS
The purpose of maneuvering during slow flight is to
help you develop a feel for controlling the gyroplane at
slow airspeeds, as well as gain an understanding of how
load factor, pitch attitude, airspeed, and altitude control
relate to each other.
Like airplanes, gyroplanes have a specific amount of
power that is required for flight at various airspeeds, and
a fixed amount of power available from the engine. This
data can be charted in a graph format. [Figure 20-13]
The lowest point of the power required curve represents
the speed at which the gyroplane will fly in level flight
while using the least amount of power. To fly faster than
this speed, or slower, requires more power. While
practicing slow flight in a gyroplane, you will likely be
operating in the performance realm on the chart that is
left of the minimum power required speed. This is often
referred to as the “backside of the power curve,” or
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：ROTORCRAFT FLYING HANDBOOK2(67)
