Vx (best angle of climb) is decided by maximum surplus [b]thrust[/b].
Vy (best rate of climb) is decided by maximum surplus[b] power.[/b]
Both of these in turn depend upon [b]both[/b] engine performance and aerodynamic performance of the airframe.

Best L/D ratio on the other hand depends [b]only[/b] on the aerodynamic performance of the airframe as in gliding.

It's quite possible that when the aerodynamic performance is at it's best, the engine/propeller combination may not be. There is no reason to assume that flying at the best L/D ratio will give best climb performance (angle or rate), because those items depend on the engine/airframe combination.

This is what I thought, however the question was very specific in relation to looking at L/D during Vx and Vy and that is what confused me a considerable degree. I have though that during a Vy climb, there is in general a better L/D compareed to a Vx climb.
Would this be the case? In both climbs, there is a L and a D, so in which scenario is it better. The RPL question was of that nature so even my flight instructors were confused when I raised the question with them

Kind regards

Ravi

No matter what the aeroplane is doing, there is always an associated lift/drag ratio. It's difficult to say whether or not Vx or Vy is associated with the best lift/drag ratio for a particular aeroplane. What matters is the surplus power or surplus thrust available at any given speed. If you put a new engine in the aeroplane, Vx and Vy would change even though the airframe was the same.

If you can find the actual wording of the question you are referring to maybe that would help.

Thanks Sir, Ill try and find
Regards
Ravi