Originally Posted by
Waterhorse
...Essentially, each takeoff is planned so that you can lose an engine at the most critical point of the takeoff and then miss all obstacles in the departure lane by 35 feet.
Assumes you have more than 1 engine
. Also depends upon the aircraft - and in particularly jet vs propeller - noting that the take off angle is essentially limited (unless in a performance aircraft).
(One time, in a little Cessna 172, we approached BWI at commuter time, so had to wait for a landing slot - eventually we got the go ahead to land (15L) and the instructor (thankfully) took control, put on full flaps, and what seemed to be a nose dive towards the runway, pulled up at the last moment and came to a stop about 25m along the runway).