Originally Posted by
Ian W
A^2 I think you are getting carried away with the turns being air radius turns and forgetting your basic physics the the aircraft is actually ground referenced, for acceleration and deceleration.
1, Take a 3 ton weight that is stationary that then turns along a rate 2 turn radius and accelerates to 120kts in 30sec
2. Take a 3 ton weight that is traveling at 120kts that then turns along a rate 2 turn radius and decelerates to stationary in 30sec
Your argument is neither of these weights experience any acceleration. I say that is obviously false.
My understanding is that the force in the turn to hold the weights in the turn (centripetal force ꟺ) accelerates the weights as it is (as you say) a change in velocity that can only come with application of a force. The ground radius described by a slow moving (compared to the wind) aircraft in an air radius turn is uneven stretched by the wind velocity vector. In consequence the centripetal force ꟺ to accelerate the aircraft (to change its velocity vector ) is uneven. An aircraft with a tight ground radius first being accelerated more at first while the aircraft with a wide ground radius first is accelerated less at first. These ꟺ accelerations - changes in velocity vector - must be added to the ground speed accelerations (decelerations) These differences will only really be apparent when the wind velocity is close to or a large fraction of the aircraft velocity.
You are on the right lines talking about acceleration. Particularly that tangential acceleration is different to centripetal acceleration
for an aircraft
These other guys dont get it