Originally Posted by
k.swiss
Additionally in terms of slowing down, which do you need to plan more track miles for? A lighter aircraft will take time to slow down due to its inertia. But a heavier aircraft will also take time to slow down because of its momentum, sometimes you need to drop the gear for example.
I didn't see this before, I think you edited it in.
Inertia and momentum functionally mean the same thing here, and the heavier plane has more of it; and will take more time and distance to slow down because of it.