"Ramapriya" wrote in message
ups.com...
Is it common to see planes commencing their takeoff roll before a
just-landed aircraft has fully turned off into the exit? That clearly
happened in the incident I wrote about too...

Define "commencing". The way I read your initial post, the departing
airplane was not on the runway yet. So, the first movement would be simply
to get onto the runway. That would be perfectly acceptable. If the runway
is cleared by the time the departing aircraft gets lined up, they may
receive a takeoff clearance without any interruption, making it appear as
though they were cleared for takeoff earlier, even when they weren't.

Frankly, I'd think the whole "smoke from the tires" thing would have been a
suitable caution to you to not assume too much about what you think you are
seeing. So much goes on "behind the scenes" in the way of coordination, and
it's hard to know from outside the airplane exactly at what points the
various steps of the sequence of taking off are actually occuring.

Pete