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back and forth, concurring with the launch crewmember’s
takeoff signal. The procedures may differ somewhat
from site to site, so follow local convention.
As the launch begins and the glider accelerates, the
launch crewmember runs alongside the glider, holding
the wing level. If there is a crosswind, the launch
crewmember should hold the wing down into the
wind, but not in a way as to steer the glider from the
wingtip.
When the glider achieves lift-off airspeed, the glider
pilot eases the glider off the ground and climbs to an
altitude within three to five feet of the runway surface,
while the towplane continues to accelerate to lift-off
speed. The glider pilot should maintain this altitude by
applying forward stick pressure, as necessary, while
the glider is accelerating. Once the towplane lifts off, it
accelerates in ground effect to the desired climb airspeed,
then the climb begins for both the glider and the
towplane.
During the takeoff roll, use the rudder pedals to steer the
glider. Control the bank angle of the wings with aileron.
Full deflection of the flight controls may be necessary at
low airspeeds, but the flight controls become more
effective as airspeed increases. [Figure 7-3]
In most takeoffs, the glider achieves flying airspeed
before the towplane. However, if the glider is a heavily
ballasted glider, the towplane may be able to achieve
liftoff airspeed before the glider. In such a situation,
Ground Track
Crab into the wind to track the
runway centerline until clear of
obstacles and terrain features.
Figure 7-3.Tracking the runway centerline.
7-4
and until the ailerons start becoming sufficiently effective
for maneuvering the glider about its longitudinal
(roll) axis. With the aileron held into the wind, the takeoff
path must be held straight with the rudder. This
requires application of downwind rudder pressure,
since the glider tends to weathervane into the wind
while on the ground. [Figure 7-4]
As the forward speed of the glider increases and the
crosswind becomes more of a relative headwind, the
many mechanical application of full aileron into the
wind should be reduced. It is when increasing pressure
is being felt on the aileron control that the ailerons are
becoming more effective. Because the crosswind component
effect does not completely dissipate, some
aileron pressure must be maintained throughout the
takeoff roll to prevent the crosswind from raising the
upwind wing. If the upwind wing rises, exposing more
surface to the crosswind, a “skipping” action may
result, as indicated by a series of small bounces occurring
when the glider attempts to fly and then settles
back onto the runway. This side skipping imposes side
loads on the landing gear. Keeping the upwind wingtip
slightly lower than the downwind wingtip prevents the
crosswind from getting underneath the upwind wing
and lifting it. If the downwind wingtip touches the
ground, the resulting friction may cause the glider to
yaw in the direction of the dragging wingtip. This could
lead to loss of directional control.
While on the runway throughout the takeoff, the glider
pilot uses the rudder to maintain directional control and
alignment behind the towplane. Yawing back and forth
behind the towplane should be avoided, as this effects
the ability of the towplane pilot to maintain control. If
glider controllability becomes a problem, the glider
pilot must release and stop the glider on the remaining
runway. Remember, as the glider slows, the crosswind
may cause it to weathervane into the wind.
Prior to the towplane becoming airborne and after the
glider lifts off, the glider pilot should turn into the wind
and establish a wind correction angle to remain behind
the towplane. This is accomplished by using coordinated
control inputs to turn the glider. Once the towplane
becomes airborne and establishes a wind
correction angle, the glider pilot repositions to align
behind the towplane.
COMMON ERRORS
• Improper glider configuration for takeoff.
• Improper initial positioning of flight controls.
• Improper use of visual launch signals.
• Failure to maintain alignment behind towplane
before towplane becomes airborne.
• Improper alignment with the towplane after
becoming airborne.
• Climbing too high after liftoff and causing a
towplane upset.
TAKEOFF EMERGENCY PROCEDURES
The most common emergency situations on takeoff
develop when a towrope breaks, there is an inadvertent
towrope release, or towplane loses power. There are five
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Glider Flying Handbook(57)
