Originally Posted by A33Zab
But I get the impression I failed..........
- yes, you did. By 'omitting' the vital part "This remark is given in the mentioned FCOM 3.....when a FCTL STAB CTL FAULT is present." which others have now posted you in fact 'raised more questions than you answered'.
Your line
"The FCPC gets ADR & IR information to The FCPC gets ADR & IR information to compensate for speed.." makes me again 'board the train' and ask exactly what ADR info the FCPC gets.to 'compensate for speed.'. You see what bothers me is that I don't think anyone here, and I include the software and system designers, can possibly (or do) understand the intricate processes that system failures can inject. There are simply too may variables and too little 'beta testing' time. It would be a breeze for some clever software writer to give the THS access to a IAS/angle/alt/c of g table and have it automatically adjust its datum concept. He/she might then go away thinking, 'Haven't I done well? One less stream of THS follow-up signals associated with speed change. Look - it KNOWS exactly where it should be for 1g at 230kts, 190kts, etc'
Now, once you 'inject' a speed input into the THS setting you begin to open 'maybe' doors onto the behaviour of the mid-Atlantic 340 and possibly 447 and others. I note the evident resistance in the AB community to accept that anything could be wrong but I do not admire it.
To pick up on MR Optimistic's post #968 - indeed, I did suggest that following a spate of BOEING (
everyone see that?) and then the AB PGF THS triggered accident/incidents there should be some physical intervention (a 'wake-up call', if you like) required by a crew to permit THS settings beyond a certain value. This could well have saved 447.
I appears that autotrim, whether it be A/P driven in the 737 or in manual flight, has a lot of fatalities to answer for.