4. LESSON 20 - LANDING IN STRONG WINDS
Key points:
- Wind speeds decrease near the ground: ‘the wind gradient’
- Fly a steeper approach with a higher airspeed
- Be prepared for the airspeed to reduce and take prompt action to restore it
- Anticipate turbulence
Approach and landing in strong winds require the same fundamental techniques that are used in lighter winds, but with important adjustments. Your base leg needs to be closer in than normal and the drift correction needed will be very apparent. Your instructor will show you the steeper approach angle that requires half to two-thirds airbrake and the higher airspeed used. An increment of half the surface wind speed is common. Use airbrakes and elevator, just like normal, to maintain a steady approach angle and speed, but be prepared for things to change. In particular, do not allow either a flattening angle or reducing speed.
Round-out and touch down will be normal, albeit from a slightly more nose down attitude. If you find your speed too low, normal actions (nose down; airbrakes in) will be effective, but must be prompt and assertive.
WIND GRADIENT
It is wind gradient that can, predictably, change things: a marked reduction in speed as the glider gets closer to the ground. You will see this as a reduction in airspeed at some stage of the approach, sometimes quite sudden. You will need to apply normal techniques for speed control, but, as these may not have time to take effect, you will need a higher approach speed to start with. Tips:
- Do not adopt an approach angle so steep that full airbrake is needed
- Be ready for the speed reduction
- If you address the speed reduction in time, small simultaneousforward movements with both airbrake and stick usually work well
The illustration shows the airspeed on final approach increased for the strong windspeed (1) and the final approach flown with the following errors(2):
- Insufficient airspeed, noadjustment for wind
- Airspeed indicator notregularly monitored / noairspeed corrections
- Stall / hard landing
Turbulence caused by trees
TURBULENCE
If you fly the final approach over obstacles, buildings, tall trees or bushes on the windward side, you should expect strong turbulence. When wind encounters an obstacle the direction and strength of the wind can suddenly change. Turbulence does not, however, change the fundamental pilot actions described here.
