4. LESSON 15 - WINCH LAUNCHING IN CROSSWIND
- Before even getting into the glider, assess the wind, watch other launches and estimate the drift correction you will need
- On the ground, use the rudder to keep straight
- Apply the drift correction once in the full climb
- Maintain the drift correction until the launch is finished
CHECK THE WIND SPEED AND DIRECTION
You should review the weather situation before getting into the glider. Before every winch launch, you should check the windsock to determine whether you will be launching with crosswind. During most launches, you will experience at least some element of crosswind, which makes every winch launch unique. If other gliders are launching before you, keep an eye on the amount of drift correction that they are applying to determine how much you will probably need to correct yourself. Without correcting for crosswind, you risk being drifted off course. Not only does this prevent you from following the ground track in the direction of the winch, it will also risk the cable being dropped outside the airfield or onto obstacles.
If you do not correct for the drift your launch may be terminated by the winch driver in the interests of safety for those on the ground: you will then have to deal with a launch failure.
During the initial acceleration you have to take account of the weathercock (or weathervane) effect (1). A weathercock always points into the wind because its tail is pushed back by it. A similar thing happens with the glider’s fin. If the wind is blowing sideways towards your fin, it will try to turn the glider’s nose. You can prevent the glider from turning sideways by using some opposing rudder. If, for example, the wind is coming from the right, you will need to apply the left rudder when rolling on the ground.
It is very important to keep the wings level (2) and to react quickly to a dropping wing; the crosswind will make it a lot harder to get your wings level again. Ensure that you start the launch with some into wind aileron if necessary and if you cannot keep the wings level, release immediately before the wing touches the ground.
LAYING OFF FOR DRIFT
After you have established the glider into the full climb, correct for drift (3). It is difficult to precisely judge the drift during a launch, hence an assessment before starting is necessary. Sometimes, aiming at a cloud ahead may help. Use coordinated aileron and rudder to select your chosen angle of bank towards the wind. Drift correction does not need large angles of bank or large control movements, but does need to be maintained until the launch is complete.