Originally Posted by
Rananim
Dozy
So what are you implying?That there was conspiracy to deceive and obfuscate prior 1994 but everything 's been above board since?
Hi Rananim, long time no see...
Not at all. They were overconfident in the abilites of their systems prior to 1994, that's for certain - and as such predisposed to put things down to pilot error when interface issues should have been looked at (the dual-mode Vertical Speed and Flight Path Angle in the Honeywell FMC being a major case in point, but the same computers were used in other manufacturer's aircraft). Airbus weren't alone in trying to point the finger at pilots in the '90s - Aircraft manufacturers are billion-dollar corporations open to massive liabilities claims and as such their legal departments will tend to demand it - look at how Boeing tried to pass the 737 rudder PCU issue off as pilot error until the NTSB had the "eureka" moment and tried a thermal shock test.
Would you say there are any latent dangers in this autotrim design in abnormal ops or that the pilots always instantly and intuitively recognize the transition from auto to manual?
My honest answer is I don't know, but the fact is that the inputs made to the system were way in excess of any input that should have been applied at cruise level. As (I think) PJ2 says, manually controlling the Airbus via sidestick at altitude requires light thumb pressure in pitch, and gentle lateral movements. This guy wasn't taught how to handle the thing, so he's bashing it on the stops.
Would you say that the stall inhibit below 60 is excusable in design terms as its outside the realms of probability?
I wouldn't say anything other than that design tends to happen at the limits of what is known. I definitely think the logic needs looking at, but I find it difficult to be too hard on the aircraft and systems designers for not contemplating what would happen if the aircraft lost all speed data and ended up in a mushy stall due to overcontrolling. For all we know the stall warning on other modern airliners has similar inhibit modes, and I'm sure Airbus will share whatever information they have in that regard.
Would you say that the SS is ideal in a multi crew environment especially when considering scenarios where stick input must be timely and CORRECT(stall/x-wind/sev turb etc)?They have the stick in fighters but thats one man.Why did AIrbus employ it in commercial airliners?To be NEW?You seem to be an avid Airbus apologist so I'd like to know.
For a start, I am an apologist for no-one, see my earlier post for further details there (should only be a page or two back [EDIT -
http://www.pprune.org/rumours-news/4...ml#post6622053]). Secondly, if you're going to start an airliner design from a fresh sheet, why not? Yokes can be a pain in the ar*e, and have noticeably been used as a crutch in certain situations (some of which happened after the A320 was well off the drawing board) when they had been effectively rendered completely useless. Sidesticks are smaller, lighter, de-clutter the flight-deck, allow more freedom of movement and the lack of backdrive makes the system less complex (technophobes don't even want to *think* about the numbers of lines of code required to make the B777 yoke behave like the old-school ones). It would also appear that the majority of people on here who have an issue with the sidestick have never used one. Neil Armstrong certainly didn't have a problem with them...
Do you have an opinion on why BEA withdrew the stall logic recommendation(factors affecting safety can and must be included in initial/interim reports but maybe theres a valid reason)?
Presumably to clarify what the situation regarding stall warning actually is. This is an interim report after all, so let's wait and see what the final report says. I have a strong suspicion that stall warning logic is a complex beast that's going to need to be looked into by all manufacturers. Stall warnings and pilot's responses to them have been a prickly issue since at least 1972 and the BEA548 Trident accident.
Do you have an opinion on why no mention was made of the Captain's decision to leave the cockpit even though he now appears to have known that weather was up ahead?
Not at all, other than from a layman's perspective (in airline pilot terms) it appears that AF has a few CRM issues it needs to address if it hasn't already done so, but primarily, I believe that placing two F/Os in the flight deck - in the ITCZ at night notwithstanding - when neither of them has had any high-altitude manual flight training is frankly inexcusable.