Originally Posted by
k.swiss
Gents I understood nothing.
Either I dust off the books and get to grips with such concepts as drag-curves and LR ratios once again, or someone truly could explain like I am five.
Do you accept that the heavy aircraft and light aircraft both have the same glide ratio but on the heavier aircraft it occurs at a higher speed (min drag speed is higher on the heavy aircraft)? And that flying faster than this speed will increase the descent angle?
Imagine the heavy aircraft is so heavy that the best glide speed is the same as Vmo. In this case it can’t descend steeper than best glide. Now make it a bit lighter, give it a min drag speed of Vmo - 20 knots. Now it can go a little bit faster than best glide and therefore a bit steeper. The lighter it is, the more margin there is between best glide and Vmo, the steeper it will descend at Vmo.
So the lighter aircraft can descend more steeply. The lighter aircraft will also slow down more quickly due to having less momentum.