The Windward Turn Theory

[Jet_Fan]

Originally Posted by Wizofoz

ET TU Wiki-

https://en.wikipedia.org/wiki/Speed

in everyday use and in kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.

A position can't have a negative rate of change.

According to NASA: https://www.grc.nasa.gov/www/k-12/airplane/move2.html

If the plane took off to the West it would have a 20 mph tail wind (wind at your back). This gives a negative wind speed. At lift off, the airspeed is still 100 mph, the wind speed is -20 mph and the ground speed will now be 120 mph.

and:

Comparing this example with the ground reference, we see that the magnitudes of all the velocities are the same, but the sign of the wind speed has changed with the reference velocity direction. For a ground reference, we chose a positive wind velocity to be in the same direction as the aircraft (towards the nose). For an aircraft reference, we choose a positive wind velocity to be towards the tail.

Originally Posted by Winemaker

There is no negative speed.

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