Originally Posted by
Retired DC9 driver
I've demonstrated a 6500 FPM descent in a light A-319. You need to disconnect the autopilot, hand fly to get more flight spoiler extension. But it went down in a hurry. LA Centre had asked us to "expedite descent". My F/O looked a little concerned..
But I realize this thread is about the 787. I only flew the 767 plus the Airbus.
The speed brakes on the 787 are phenomenally powerful, and using full speed brake coupled with a loss of cabin pressure triggers a further extension. I’ve seen upwards of 10,000fpm in the sim, and easily 4000fpm with the speed held back at about 250kts.