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Is this true that during a flight with a crosswind the drag increases due to the fact that the relative wind blows at a certain angle to the aircraft's nose but not precisely in the opposite direction to its flight path as it would be without a crosswind? enter image description here

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    $\begingroup$ Please give words to the labels in the diagram. $\endgroup$ Nov 13 '18 at 10:45
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    $\begingroup$ Yet another suggestion-- it is normal to draw the arrowhead at the front of the vector, not in the middle. Drawn in the middle it looks sort of like you are adding two vectors together in each leg. Likewise avoid the multiple arrowheads on some of the vectors. But the main thing is to draw the "relative wind" arrow equal in length and opposite in direction to the airspeed arrow, The nose of the plane should be at point A, and the plane should be pointing exactly along the direction of the airspeed arrow. The arrow on the left side. Does that make sense? $\endgroup$ Nov 13 '18 at 16:44
  • $\begingroup$ In your example the ground speed is lower because the flight speed vector does not point straight to the destination. This might seem like drag is higher, but all that is higher is actual flight time to the destination. $\endgroup$ Nov 13 '18 at 20:42
  • $\begingroup$ If you flew it the whole way in a sideslip like your drawing shows, yeah, there'd be a drag penalty. You'd also be holding a bank angle the whole time. $\endgroup$
    – TomMcW
    Nov 13 '18 at 21:55
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No, it's not true-- have you ever seen a birds feather's blowing sideways?

We fly INSIDE of the wind, not AGAINST the wind.

You should draw the airplane symbol on the left-hand leg of the triangle, pointing in the same direction as the left-hand leg, and you should draw the "relative wind" arrow equal in magnitude and opposite in direction to the airspeed vector, i.e. the left-hand leg of the triangle.

Consider the fact that many of us have had the experience of actually BACKING UP in flight, relative to the ground. Now, do you think the air was flowing backwards over the wings?

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Is this true that during a flight with a crosswind the drag increases due to the fact that the relative wind blows at a certain angle to the aircraft's nose but not precisely in the opposite direction to its flight path as it would be without a crosswind?

Nope. Normally, pilots maintain coordinated flight. This means that they always point the nose of the aircraft directly into the relative wind, regardless of which way the wind is blowing.

(During straight and level flight, keeping the nose pointed into the relative wind is easy. For the most part, the vertical stabilizer does it for you.)

The aircraft's actual flight path is totally irrelevant to aerodynamics. In other words, the plane doesn't know or care what the flight path is. The flight path affects one thing and one thing only: the motion of the ground underneath the aircraft.

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