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Old 22nd Aug 2011, 10:41
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AlphaZuluRomeo
 
Join Date: Nov 2010
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Hello

Just quibbling a bit...
Originally Posted by Clandestino
Most important and most often checked information in "blind flying" is attitude. If one cannot read it properly or cannot maintain it properly, the rest of instrument scan is in vain.
A friend of mine, chopper pilot (ex-military), told me of his IMC trainings without ADI/horizon, and how he (and his colleagues) managed to do some nav/airfield -relatively- complex circuits with "just" heading (and its rate of change), airspeed, altitude&V/S and, of course, a chronometer. It was hard, yes, but they just did it.
I do agree, however, that attitude is the #1 parameter, and on everything else about instrument flying you wrote in the quoted post.

/quibble & old memories


@ Lyman:
I'm sorry, I don't understand why you keep saying that the g-demand law was confusing for the pilot or that the pilot somehow "believed" he was in Normal Law.
- Normal Law is a g-demand law too. In other words, there should be no significant difference in handling/aircraft response on the pitch axis ; the differences are the protections, and the fine gain tuning.
- Alternate Law was announced. Yes, it was the PNF who said that. Why? Because it's his job as PNF!
"PROT LOST." If after that the PF still believes he's in Normal Law......
I strongly disagree on the "flaw" you promote regarding the g-demand law. As I'm not sure that everyone here understand what is a g-demand law, let's try to KISS:
Basically, a g-demand flight law is when, for a given position of the stick, the aircraft delivers the same amount of g regardless of the speed, altitude, pressure... etc.

Originally Posted by Lyman
IF THE THS had been neutral, the pilots could have pulled TIRE TIRE TIRE!
and the a/c would have recovered in spite of the wrong input. Had they continued their pull, it would have STALLED AGAIN.
I'm waiting to see how you can write that. Have you made calculations/simulations? Stall recovery technique was never to pull-up. Not on FBW planes. Not on conventionnal planes. Not on gliders.

Originally Posted by Lyman
Do you see? The a/c prevented a recovery.
I see your point. I do agree that a conventionnal aircraft would have performed differently. If the A330 had had the autotrim-up-movement-inhibition-when-stall-warning-is-ON we discussed above, it would also have performed differently (and better).
But I don't agree with your conclusion, which is -if I understood correctly- that g-demand FBW should be discarted. Because if you discart this, you loose far more than you win.
One has to know its tool. And once again: if stalled, push, don't pull. Whatever you're flying, it will always be the correct input (that's, by the way, what the "new" "all-around" procedure by FAA-AESA&Boeing-Airbus says).

Last edited by AlphaZuluRomeo; 22nd Aug 2011 at 12:47. Reason: still learning to spell, it seems... ^^
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