The objective of this lesson is to enable you to fly straight towards your goal in a crosswind.
A crosswind refers to any wind direction that is neither straight ahead (headwind) nor directly from behind (a tailwind). Neither of these will affect our path, although they will affect our speed over the ground. Anything other than these is a crosswind.
The stronger the wind, and the greater the difference between our target and the wind direction, the more it affects our path.
This difference between the wind direction and our target is known as the crosswind component. A 5kt breeze with ten degrees of crosswind component won’t make a lot of diffence. A 20kt breeze with a crosswind component of 90 degrees will.
While airborne, we are travelling through a parcel of air. It’s obvious then that if our parcel of air is moving sideways compared to our intended path over the ground, we will be carried sideways, downwind. If you maintain your original heading all the way across this parcel of air, you will arrive downwind of your goal. If you adjust your heading so that you are always pointing towards your target, you will fly an increasingly curved path across the ground, eventually arriving from directly downwind. To travel efficiently by keeping our track straight, we must aim upwind of the target, and aim to keep it stationary in our view (not sliding sideways across the canopy). How far we aim upwind depends on the strength of the crosswind component (and how fast we are flying).
We learnt that flying straight and level in calm air was quite straightforward – the glider does most of the work and we simply keep it on track with minor corrections.
How do we do it?
As you turn across the wind, and decide which way you want to track, roll out of the turn so that you are heading ten to twenty degrees upwind. You can quickly judge whether you need to adjust this. Then fly wings and string level at your desired speed. Watch your target, or track, aiming to keep it stationary in your view. If it is sliding upwind or downwind, you need to ease the nose round a little with a coordinated turn in that direction. On a gusty day, with varying wind strengths, you will need to monitor this and adjust frequently.
Scenario and Demonstration
This demonstration and exercise takes place in a 10-20kt cross wind, at 90 degrees to our target. You’re flying the Standard Cirrus.
We especially want to manage our track across the wind when we are approaching the runway, particularly if it is narrow and we must land on it. This demonstration replicates that situation by aiming to fly along a runway against a decent crosswind. This is NOT the way to behave above a runway in real life – it is being used here as an obvious ground feature to make the drift, or need to head upwind of the target, as apparent as possible. When you can do this, traversing the open countryside at a safe height is a piece of cake.
The video is best viewed in YouTube in HD in Full Screen mode, to easily see the on-screen messages and instruments during the demonstration. Use view, pause and rewind as needed to grasp the content and timing of the messages displayed, then focus on the action.
Performing the Exercise
Your goal is to fly along the runway, keeping the centreline in the same place on the right hand side of the canopy. When you get to the far end it is time to end the exercise and repeat. When you can maintain a steady track along the runway, try varying your speed. After that, you’ll be ready for some turbulence!
Further Reading and References
Gliding From Passenger to Pilot, 2nd Edition: Page 87-88
BGA Instructors’ Manual, 4th Edition: Section 2, Chapter 9