Originally Posted by
gums
Salute!
While we are on the software.....
It has been mentioned that the Aibus FBW models do not have inherent speed stability IAW the Part 25 requirements. This was mentioned because of the 737 STS implementation with its "helpful" trim when changng speed/AoA. This hints at very low drag changes when AoA changes, right? The Airbus prolly has great inherent speed stability but it's hard to find out due to the flight control laws. Same with my Viper.
If you choose a gee command control law for pitch, then the sucker will press on straight ahead and not change pitch to maintain last "trim" speed/AoA. I flew the AFTI sim using a pitch rate law and it wasn't as comfortable as gee command, and didn't have speed stability either. Only an AoA command law had what we old farts were used to. So the Viper pilots and 'bus drivers just point where they wanna go and use power fpr speed. Big deal, and doesn't take two minutes to realize it. With gear down, the Viper law is still gee command but includes an AoA bias and stronger pitch rate dampening. It is like a sloppy Cessna, heh heh.
Gums sends...
Its opinion, but the difference in control method is why the Bus is nicer to fly than the 777/787 as far as pitch/roll goes... in flight, and in normal modes. The instrumentation sucks, the reversionary modes and the ECAM/checklists/FCOM/OEB's are a PITA. Conventional aileron control on the 777/787 make for happier crosswind takeoffs and landings than the Bus. Manoeuvre demand/g is nice, but the rest sucks.
As the saying used to go...
Boeing: built by rocket scientists for idiots
Airbus: built by idiots for rocket scientists
Both are good aircraft, we have issues with putting humans into them as part of the loop, but taking the human out guarantees failures.