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Old 29th Jun 2011, 19:38
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A33Zab
 
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Why does the system, not the pilot, try to maintain an AoA that is not necessary?


If the "protection" limit is "x", no problem. But the system should strive to achieve the trimmed gee ( one gee for the 'bus", as the pilots can't trim for a gee as in the other FBW system that has over 4,000 jets flying in dozens of countries) ? Pilots input commands other than one gee, to the limits, but the jet should not insist upon flying at the alpha-prot value, which is higher than necessary for most flight conditions. In that "other" jet, if you relaxed stick pressure, then it tried to achieve the commanded gee, not the alpha.

The alpha-prot should be a "limit", and not a "command" from the system.



HIGH ANGLE-OF-ATTACK (AOA) PROTECTION
High AOA protection enables the PF to pull the sidestick full aft in dangerous situations, and thus consistently achieve the best possible aircraft lift. This action on the sidestick is instinctive, and the
high AOA protection minimizes the risk of stalls or control loss.
High AOA protection is an aerodynamic protection:
• The PF will notice if the normal flight envelope is exceeded for any reason, because the autopitch trim will stop, the aircraft will sink to maintain its current AOA (alpha PROT, strong static stability), and a significant change in aircraft behavior will occur.
• If the PF then pulls the sidestick full aft, a maximum AOA (approximately corresponding to CL Max) is commanded. In addition, the speedbrakes will automatically retract, if extended.

I continually bring up "that other jet", as there are thousands more than the Airbus flying and thousands more pilots flying it. The number of LOC incidents due to sensor failures and system failures is down in the noise level considering the thousands of flights each day for the last 30 years.

just more thots .....
No problems with that, I grew up with the B747 series & MDC10, even have minor B777 experience to compare with.
I don't disagree that there are more other jets flying than A. but that doesn't mean A. is equal to 'stupid' cows and are only engineering 'ridiculous' systems compared to the cowboys.
Airbus was formed by manufacturers who did earn their credits in the past too.
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