Originally Posted by
Winemaker
His ground speed is 10 knots. His ground velocity is 10 knots in the direction of the wind. Speed and velocity are two different things. A good definition of velocity is from Wikipedia, which I use for its clarity:
Please note that velocity must have a frame of reference and that's what's leading to all this BS. Define your frame of reference then do all the vector sums from that frame. You can't mix both the 'air' reference and the 'ground' reference. Use one or the other. There is no energy generated when a plane turns constant circles in a constantly moving air stream. The velocity of the reference air stream over the ground doesn't make one whit of difference to the aircraft.
I'm a dumb winemaker and even I understand this.
As you love wiki so much, let's see what it has to say about groundspeed:
Ground speed can be determined by the
vector sum of the aircraft's
true airspeed and the current wind speed and direction;
a headwind subtracts from the ground speed, while a
tailwind adds to it. Winds at other angles to the heading will have components of either headwind or tailwind as well as a
crosswind component.
What is 50 - 60?