"Larry Dighera" wrote in message
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The point I'm making is, that of the 360 degrees available for winds
to intersect the intended course, only about 15% are able to result in
a net ground speed increase.

This is from memory, so I'm sure someone will correct me with a more
detailed analysis.

Of course.

It depends on the strength of the wind.

For example, if you are flying 100 knots, a 20 knot wind from 10 degrees aft
of a direct crosswind gives you a 1.5 knot boost in speed, but a 40 knot
wind from the same direction slows you by 1.1 knots.

The stronger the wind, the more directly behind you it can be and still slow
you down.

That said, your statement that only 15% of the available degrees result in a
true tailwind is plainly false. That would be an arc of only 7.5% degrees
to either direction of straight aft of your heading, when in fact modest
wind speeds even only slight aft of your heading result in a net increase in
groundspeed. And it ignores the fact that it's not simply the direction of
the wind, but also the speed.

It's true that more than 50% of all wind directions and speeds result in a
headwind, but it's only *slightly* more than 50%. Certainly not nearly
enough to explain the original poster's experience.

Pete