Hmmm interesting.
RRAMJET, Emergency descent v Line operations?
777 did overshoot, but didn't you just describe that as an emergency situation? Fair enough, but the earlier posts are suggesting reducing to 1000fpm as a matter of course in all ops.
FWIW, my coy ops manual and manufacturers ops manual says that my 1980's vintage Smiths AFGS will very likely bust the target altitude in an EMERG DESC. It has never busted a target in day to day ops, sometimes with full airbrake, bastard trim and 3000fpm. Presumably Mr Smith knew what the autopilot could and could not do when they installed it, and then told the pilots of this via their manual.
What does yours say about AP controlled EMERG DESC in the B777?
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Sorry LEM, still don't buy the need to do the autopilot's job for it if your concern is overshooting.
Do you not set your TCAS to look ABV or BLW when climbing/descending to show targets at greater than 2700' sep? At 7200' or 9700' (dep on software revision), and 12 nm range on basic TCAS display, that is at least 2 minutes to spot a fellow below you.
Basic airmanship? To not ruin a colleagues day by avoiding setting off bells and whistles in his cockpit and spilling his coffee, yes. To not approach a hazard (other aircraft, ground, etc) at a high speed (vertical or otherwise) with corresponding great momentum, yes. To have and apply situational awareness before taking such action, yes.
To do it all the time without applying situational awareness and making decisions, no, that is not doing the job one is paid for. If such were necessary, Messrs Smith, Sperry and coy would have programmed it into the unit.
Last edited by ITCZ; 28th May 2003 at 19:20.