Originally Posted by
Sailvi767
I think some of the posts on here fail to account for time to spool a fan engine while the aircraft is moving. The 777 is going to need 8 or more seconds to spool a engine.
Actually, the regulation says 8 seconds
or less from approach idle to go-around. The GE90 does it in about 6 seconds at sea level static (and the idle logic will hold it at approach idle for several seconds after touchdown before allowing decel to min (ground) idle. In addition, although idle needs to be commanded prior to stowing the T/R, the engine itself doesn't have to decel that low before the T/R will stow.
Originally Posted by
Sailvi767
Just a guess but I bet most airliners can stop from 100 knots in 1500 feet or less on a dry runway with maximum braking.
Cranbrook occurred in the middle of a snowstorm, and a runway that had an accumulation of snow at the time. They cleared the snowplow, and it would have been a non-event if the reversers used the current design logic.
Again, this would be split second decision by the PF - and their lives (along with the passengers) depend on getting it right... We design for the
possibility that they may decide their best chance is to go-around.