• 热门标签

当前位置: 主页 > 航空资料 > 国外资料 >

时间:2010-05-10 17:47来源:蓝天飞行翻译 作者:admin
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

takeoff and landing area. When the ground crewmember
has assured the traffic pattern is clear, the ground
crewmember then signals the launch equipment operator
to “take up slack” in the towline. Once the slack is
out of the towline, the ground crewmember again verifies
that the glider pilot is ready for takeoff. Then
ground crewmember raises the wings to a level position,
does a final traffic pattern check, and signals to
the launch equipment operator to begin the takeoff.
NOTE: The glider pilot should be prepared for a
takeoff anytime the towline is attached to the glider.
The length, elasticity, and mass of the towline used for
ground launching has several effects on the glider
being launched. First, it is difficult or impossible to prevent
the glider from moving forward as the long towline
is tautened. Elasticity in the towline causes the
glider to creep forward as the towline is tightened. For
this reason, the towline is left with a small amount of
slack prior to beginning the launch. It is important for
the pilot to be prepared for the launch prior to giving
the launch signal. If the launch is begun before the pilot
gives the launch signal, the glider pilot should pull the
towline release handle promptly. In the first several
seconds of the launch, the glider pilot should hold the
stick forward to avoid kiting.
During the launch, the glider pilot tracks down the runway
centerline and monitors the airspeed. (Figure 7-18,
item 1) When the glider accelerates and attains liftoff
60°
70°
30°
Release
Point
20%
Takeoff Power
Begin
Reducing Winch
Power
Figure 7-17. Winch procedures.
7-15
speed the glider pilot eases the glider off the ground. The
time interval from standing start to liftoff may be as
short as three to five seconds. After the initial liftoff, the
pilot should smoothly raise the nose to the proper pitch
attitude, watching for an increase in airpseed. If the nose
is raised too soon, or too steeply, the pitch attitude will
be excessive while the glider is still at low altitude. If the
towline breaks or the launching mechanism loses power,
recovery from such a high pitch attitude may be difficult
or impossible. Conversely, if the nose is raised too
slowly, the glider may gain excessive airspeed, and may
exceed the maximum ground launch tow speed. The
shallow climb may result in the glider not attaining
planned release altitude. If this situation occurs, the pilot
should pull the release, and land straight ahead, avoiding
obstacles and equipment.
As the launch progresses, the pilot should ease the nose
up gradually (item 2), while monitoring the airspeed to
ensure that it is adequate for launch but does not
exceed the maximum permitted ground launch tow airspeed.
When optimum pitch attitude for climb is
attained (item 3), the glider should be approximately
200 feet above ground level. The pilot must monitor
the airspeed during this phase of the climb-out to
ensure the airspeed is adequate to provide a safe margin
above stall speed but below the maximum ground
launch airspeed. If the towline breaks or if the launching
mechanism loses power at or above this altitude,
the pilot will have sufficient altitude to release the towline
and lower the nose from the climb attitude to the
approach attitude that provides an appropriate airspeed
for landing straight ahead.
As the glider nears its maximum altitude (item 4), it
begins to level off above the launch winch or tow vehicle,
and the rate of climb decreases. In this final phase
of the ground launch, the towline is pulling steeply
down on the glider. The pilot should gently lower the
nose of the glider to reduce tension on the towline, and
then pull the towline release two or three times to
ensure the towline has released. The pilot will feel the
release of the towline as it departs the glider. The pilot
should enter a turn to visually confirm the fall of the
towline. If only a portion of the towline is seen falling
to the ground, it is possible that the towline is broken
and a portion of the towline is still attached to the glider.
If pulling the tow release handle fails to release the
towline, the back-release mechanism of the towhook
automatically releases the towline as the glider overtakes
and passes the launch vehicle or winch.
CROSSWIND TAKEOFF
AND CLIMB—GROUND LAUNCH
The following are the main differences between
crosswind takeoffs and climb procedures and normal
takeoff and climb procedures.
 
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:Glider Flying Handbook(64)