Downwind turn

Fly a 20 mpg paraglider in a 15 knot wind and you'll gain a new appreciation for wind effects.

jsstevens said:
Whiskey in your water?
Sugar in your tea?
What're all these crazy questions you keep asking me?
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That ain't the way to have fun, son.
 
Stewartb said:
How do you know what others are thinking? If somebody out there doesn’t recognize that ground reference plays a part, why not explain it to them?

Imagine a big, smooth lake. There’s a ripple from the wind. A floatplane is practicing step turns. Does the turn take more space going into the wind or down wind? The lake isn’t moving. Apparently the airplane doesn’t know the wind is blowing. What forces are affecting the turns? And Dan’s correct. Fly floats on flowing water and the wind can make things very interesting.

Do you guys have a personal limit on wind velocity for taking off or landing downwind? What’s your limit? Why?
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5 knots.
 
Stewartb said:
Do you guys have a personal limit on wind velocity for taking off or landing downwind? What’s your limit? Why?
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On floats it's not the wind that's the problem. It's the waves, because you're hitting them at a higher speed relative to the water.

And the higher the wind speed the higher the waves, so it compounds quickly.
 
Stewartb said:
Do you guys have a personal limit on wind velocity for taking off or landing downwind? What’s your limit? Why?
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It seems like some here are being deliberately obtuse. Against my better judgement…

On a downwind takeoff, your ground run is longer, since you’re trying to accelerate to a given airspeed in an airmass which is itself moving in the same direction you are. Similarly, your groundspeed is higher when you reach rotation speed for the same reason. Hence, one must plan for more runway needed. In addition, some aircraft have an Operating Limitation on tailwind component on takeoff, so there may be legalities involved. Once in the air, Vy will not change with a headwind or tailwind, since it’s based on time to altitude with no ground reference. On the other hand Vx will change, since it’s based on distance to ground-based obstacles, or the rising ground itself. Landings are also ground-based, and it’s the transition from flying in a moving airmass to landing on a ground-based runway that tends to give student pilots fits. For seaplanes, substitute “surface” for ground, but the same principles apply.

This should all be painfully obvious to the experienced pilots here, but we have students and non-pilots here as well. It does them a disservice to mix takeoffs, landings, and other ground-based maneuvers into a discussion on the “downwind turn” and the effect, or lack thereof, of “wind” on an aircraft maneuvering in a moving airmass.
 
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I believe the "downwind turn" referenced in the OP is the turn from crosswind to downwind.
Personally, none of the pattern turns ever worried me much. Just keep your airspeed up (above stall speed + a cushion for the turn's loss of lift), and angle of attack down for the cross-to-down turn.
Now, let's discuss cross-control correction for a final overshoot from base. :popcorn:
 
dbahn said:
On floats it's not the wind that's the problem. It's the waves, because you're hitting them at a higher speed relative to the water.

And the higher the wind speed the higher the waves, so it compounds quickly.
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When I think of wind on floats I think of flying on rivers. Managing current and wind doubles the fun.
 
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