Subscriber question:
"If Tower assigns an intersection takeoff, must I accept? Conversely, is it okay to ask for one to save time?" — Tom R.
Paul:
“There’s sometimes a good argument for accepting, or even asking for, an intersection takeoff, but this is a classic case of playing the probabilities. Nothing is more useless than runway behind you. But probably, you won’t need it, right?
The compelling reason you might need it is a sudden runway obstruction like a vehicle or animal, a contaminated surface or—worst case—an engine failure.
Engines do quit on takeoff. A research project on engine failure I’ve just completed revealed that many happen on takeoff, some just off the end of the runway or in the pattern. In that case, the more altitude you have, the more options you have. In any case, there’s no good argument for being lower rather than higher once all the pavement is behind you.
But the larger question is what does the intersection takeoff get you? Back home 30 seconds earlier? Or launching ahead of that annoying guy in the old Cherokee? Okay, three minutes maybe. Trade that against giving up altitude you might badly need when what’s never gonna happen to you finally does happen to you.
I’d never say never to an intersection takeoff. But aeronautical decision making is all about habitually reducing even small risk factors. And an intersection departure can be one of those.”
Have you ever refused an intersection takeoff assigned by Tower?