I am having trouble trying to rationalise the following.
If you fly at any speed below VMD you will need to use more thrust according to the total drag curve.
[edit for clarity: I am talking about the FORCES curves of THRUST REQ./DRAG)
But, the speed for max. endurance (least fuel use and time in the air), which I understand to be VMP, is below VMD.
How can you have to use more thrust yet still use less fuel ?
