Originally Posted by
Leonakua
"I understand the question to ask how a dual engine shutdown affects the stopping distance."
More importantly, survivability..... GEnx takes two seconds to deploy (reverse) fully. Less than three to stow... The CF6-80 (Narita MD11) similar in design. Without power, the aircraft is stranded in Pitch oscillations, interrupted by un-mitigable nose gear collisions with the runway?? Elsewhere in this thread rotor burst is (described as) an emergency that takes longer to develop than the difference between pilot intervention CutOff and TCMA CutOff...?? If so, then??? Thanks.
TCMA isn't designed to protect against rotor burst; that's a different protection system. Both are designed to act very quickly because uncommanded high thrust/speed (whether it could result in rotor burst or not) occurs very quickly, faster than crew can reasonably expect to react.
The time taken to deploy/retract reversers is irrelevant, because you cannot deploy/retract reversers when the engine is at high thrust, and TCMA is designed to deal with engines that are stuck at a high thrust setting.
Originally Posted by
Musician
I understand the question to ask how a dual engine shutdown affects the stopping distance.
Makes sense; I over-thought that.
Aircraft are generally supposed to be able to land even without thrust reversers, especially on dry runways. A single-engine TCMA shutdown should be no worse than any other single engine failure. Uncontrolled thrust is really nasty
especially on slippery runways, which is the situation where reverse thrust is actually useful for stopping distance.
Originally Posted by
Musician
I'm super sorry, but I give up.
I've asked you before to be more explicit, and to explain more, and instead you keep churning out these bangers that are impossible for me to follow.
I think this is a reference to FedEx Flight 80, which was an MD-11 that bounced, porpoised, and crashed at Narita in 2009.
If a crew had a bounced landing that bad, they could/should have applied power and gone around. If TCMA had activated (on all three engines, which again, should not happen and only occurred because RR had a software bug/lack of imagination), the crew might have been forced to land what should have been a go-around.