From 16 Flight Maneuvers,
http://www.av8n.com/how/htm/maneuver...-downwind-turn
"Summary: Changing Headwinds and Tailwinds
For ground-reference maneuvers, a steady wind has a direct effect.
For other maneuvers, a steady wind has no effect on the airplane or on the pilot in the cockpit. However, the maneuvers will appear different to ground-based observers.
In the presence of windshears, you can gain or lose energy due to the albatross effect. In real life, this means for instance that you will get slightly better performance climbing into the wind. This gives you a reason to turn downwind a little later than you otherwise would.
For any maneuver that doesn't depend on a ground reference, a steady wind has no effect on the maneuver. For example, a standard-rate turn to upwind is just the same as a standard-rate turn to downwind. You can't even determine the magnitude or direction of the wind without using a ground reference.
If you want to calculate the energy in the ground-based frame of reference, you must account for the airplane being batted by the wind. "