Re: Southwest B737 Overrun @ Chcago MDW
Dear HAND:
Regarding reverse thrust at low speeds:
You are talking about taxi speeds below 20 knots. Hooray. The southwest airliner went off the end of the runway at more than 40 knots.
I mentioned keeping reversers extended and developing thrust because there is a certain visual illusion which makes pilots think they are stopping when they are not doing so. said pilots often cancel reverse early with the engines still producing significant thrust. when canceled the thrust is no longer reversed and accelerates the plane. IF YOU HAVEN'T ever felt this on the 767 or any plane either you are: allowing the engines to come to idle prior to cancelling reverse (GOOD FOR YOU) or you haven't actually flown an airplane with reverse.
IN THE simulator ( and I am not talking microsoft) the rule of thumb is to keep reverse until the image in the sim shows you are going backwards. AS silly as this may sound to the uninitiated, it keeps you on the runway, which is the name of the game.
OH and by the way, I have seen perfectly good landings on snow covered runways only to be spoiled by slipping on the taxiway. The only saving grace was REVERSE at speeds below 10 knots.
If you have flown the 767, I encourage you to read, "Handling the Big Jets" by DP Davies (former certification test pilot for UK's CAA). Even he says to keep reverse in if there is doubt about stopping on the runway and not to worry too much about gas ingestion.
So, HAND, I hope I have made myself clear.
jon