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Old 06-11-2013, 05:35 PM   #144 (permalink)
stiletto2
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Quote:
Originally Posted by euromodder View Post
Airplanes tend to crab into the wind because of the tail at the end.

But a flag on the nose would not always point directly aft ...
Gliders, TF9 Cougars, U2s, Tomcats all have or had yaw strings to see if they are heading straight into the wind or not.
On a Harrier, there's a vane on a small mast (couple of inches high) in front of the canopy.


Depends on what you mean by "do not feel".
Unless corrected, aircraft get pushed aside by many miles due to sidewinds.
But the pilots generally won't physically feel it.
Um, they point into the wind (weather vane effect) because of the tail at the end. The yaw string would only be off center if the aircraft was not allowed to be neutral and was purposely being held off by using control input or because of gusting wind or divergent flight. Crabbing is merely a reference to its "apparent " angle and movement over the ground. Loose all reference to the ground and one could not tell how the aircraft was moving in relation to the ground. (many fatal accidents in aviation happen because of that)

I used to fly an ultralight trike and one thing I liked to do when conditions were right was to fly up to about 1500 feet above the ground when the wind up there was going just over 30 KTS. (about 35 MPH) I would fly it directly into the wind right at about 32 MPH indicated which meant I was actually flying backwards around 3 MPH. If, at the time, I was flying over clouds, in the dark or through fog and couldn't see the ground or other reference points, it's likely that I would not even know I was actually going backwards.

"Crabbing" and "side winds" are terms used when one's flight path is other than directly into or directly away from the prevailing wind direction. Any vehicle in contact with the ground is going to feel wind effects more because of its resistance to move with the air. Once it is free from the ground it will move with the air. Occupants in hot air balloons feel very little wind once free from ground contact because the whole thing moves with the wind. There is little relative air movement in their immediate space because they are moving about the same speed as the wind.

Because of friction, contact with the ground resisting relative air movement and air drag, vehicles on the ground "feel" the wind more and its effects when it is not going the same way as their direction of travel. We try to do what we can to be slipperier and less affected by the air from any direction. (but stay firmly on the ground) What ever works best for you.
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