Originally Posted by CONFiture
Which limitation did they try to bend on QF72, please remind me Clandestino.
So what happened there? There they were, cruising serenely at FL370, when all at sudden, malfunctioning protection activated and sent them to their whopping 680ft plunge, following by another enormous 400 ft dive. "Yes they were lucky this time, what would have happened if they were on short final", I can hear you scream. Well, they were unlucky to have it happened at the first place. There are no records of it happening before or after, anywhere in the world, on any FBW Airbus
AFAIK. We stil don't know what triggered the alpha prot, one of contributing factor to our continuing ignorance certainly being extreme rarity of such an events. DP Davies has treated the subject of statistically acceptable risk of protections activating when not required in chapter discussing the stickpushers. If you have third edition, it's page 131. Nothing new under the sun.
Originally Posted by CONFiture
Why don't you question SC ... He wrote that 'the protections are there in the first place because you lot kept crashing'
Can you produce figures that would support such statement ?
My apologies, I got the wrong impression you were talking about FBW Airbi hull losses, while you were referring to the loss of control accidents of non-protected aeroplanes. Aviation safety network is good starting point for research, yet again as accidents are very rare compared to number of operations, it's better to concentrate on case studies instead of statistics. Functioning protections prevent from spiral dive, stall, overspeed and overstress. It is empirically proven that one can remain within protection boundaries and turn FBW Airbus into scrap metal.
Originally Posted by CONFiture
If the XL Airbus in Perpignan don't follow the pilot request in the final dive, that's because of the G load protection to make sure that the aircraft is intact up to the crash site.
Nope. It didn't follow it because THS remained at full nose-up position throughout the event. Elevator would be unable to overpower it even if the puzzled computers had operated it in demanded sense. Again, it has everything to do with DP Davies and nothing with Ziegler's concierge.
Originally Posted by nilcostoptionmyass
If i'm on my 'dinosaur' aircraft flying at 330kts and want to pull up to 60 deg up and wash the speed off, i can, because i.m in control.
All well if your dinosaur is F-4. In the enlightened age of FDM, this would be career ending event if performed while flying transport category aircraft.
Originally Posted by jcjeant
Rocking chair in front of breakfast TV.
Anyways pilot or not we will all obtain this rating
That's an extremely optimistic view. I used to know a decent bunch of pilots who were never able to put it on their licences despite their best efforts.
Originally Posted by PBL
Originally Posted by DozyWannabe
I don't think there's a single incident where the protections have caused a hull loss - at least not when there hasn't been a major malfunction.
Yes, but please don't forget that Hamburg came very close!
I disagree. Hamburg was not protection issue, one of the contributing factors was halving the control travel while transitioning from normal to ground law. However, wrong stick input was used during decrab in winds that exceeded demonstrated crosswind component by the test pilots, aeroplane was landed on the downwind wheel and they got away with scraped wingtip fence. That's good enough control authority in my book.
There were two accidents that involved SA Airbi making heavy landings during turbulence that triggered alpha prot - St. Johns in 1999 and Bilbao in 2001. After Bilbao, alpha prot got relaxed by desensitizing it to high AoA rate of change. Of course, we don't really know whether the outcome would be better or worse in either of the cases if the protections didn't intervene.
Originally Posted by Locked Doors
To ditch an a/c you want to be as slow as possible with the minimum v/s possible.
Perhaps on some aircraft, not on A320. Desirable method is going for 11° pitch with RoD as little as possible. If you can't make the RoD, you don't sacrifice the pitch to get it. Capt Sullenberger did hell of a job out there, there's no point in second guessing what he actually ment to do or how could he done it better. I can only hope that I'll be as good as him if my time comes.