A320 Low speed stability
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A320 Low speed stability
While reading about the low speed stability, the following question arose, as nothing is explicitly said about it.
During Low speed stability (replaces AoA protection when in alternate law)a gentle nose down signal is intoduced between 5 to 10 knots above stall speed to keep the speed from falling below these values. Can the pilot override this, or not?
Thanks in advance,
During Low speed stability (replaces AoA protection when in alternate law)a gentle nose down signal is intoduced between 5 to 10 knots above stall speed to keep the speed from falling below these values. Can the pilot override this, or not?
Thanks in advance,
The A320 pilot can can override either low or high speed stability with moderate stick inputs. At least that's how it works on A320 sim, I've never flown real 320 in altn law.
It wouldn't in alternate and direct laws. Automatic setting of TOGA thrust, known as alpha floor is available only in normal law, when alpha protection prevents the pilot from stalling the aeroplane and alpha prot can't be overriden by the stick input anyway.
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A lawyer for the law
Gentlemen,
Can someone me explain how to get in the so called >alternate< or >direct< law in air ??
Please read once more yr manual before telling somebody such a thing.
There is no direct law in air. How do U want to get in ? Only when U loose all Prims and Secs, but than U have only mechanical inputs.
Of course can the pilot be so unlucky to get in a situation, where normal law in pitch control failed , but than alpha 1 Prot takes over, when this fails , Vc Prot comes, this is overideable in lowspeed only.
But for this we have the high paid chimps
Logic for the elec control is PRIM1>2>3>SEC1>2
Normal>alternate>protection and direct on GRD
Now calculate the possibility and praise Airbus
Sorry but direct law in air is a misunderstanding of the philosophy
rgds
Can someone me explain how to get in the so called >alternate< or >direct< law in air ??
Please read once more yr manual before telling somebody such a thing.
There is no direct law in air. How do U want to get in ? Only when U loose all Prims and Secs, but than U have only mechanical inputs.
Of course can the pilot be so unlucky to get in a situation, where normal law in pitch control failed , but than alpha 1 Prot takes over, when this fails , Vc Prot comes, this is overideable in lowspeed only.
But for this we have the high paid chimps
Logic for the elec control is PRIM1>2>3>SEC1>2
Normal>alternate>protection and direct on GRD
Now calculate the possibility and praise Airbus
Sorry but direct law in air is a misunderstanding of the philosophy
rgds
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Are you really talking about Airbus?
Everytime you are in alternate and lower the gear you are in direct mode. So it's pretty important to know what to do in direct law.
Or do you lower the gear on ground only?
dani
Everytime you are in alternate and lower the gear you are in direct mode. So it's pretty important to know what to do in direct law.
Or do you lower the gear on ground only?
dani
Can someone me explain how to get in the so called >alternate< or >direct< law in air ??
So, has the Airbus really changed FBW arhitecture on latest A320s from FAC/ELAC/SEC to PRIM/SEC, or what we have here is the charge of the MSFS brigade?
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They're not "so called", this is official Airbus terminology. FCOM 1.27.30 has it ver
DEAR ALL
pls check once more yr manuals, for a so called direct law U need
-triple ir fault
-triple prim fail
-two elev fault
-both eng out
in all other failure/law configs U have still protections, in alternate mode the AOA protection is still there. RYFM
Ground mode or direct law for pitch control is till 8 sec after liftoff, from 100 ft down to ground U swap into flare mode, touchdown + 2 sec direct law.
So U R really unhappy when U get >>>direct law<<< in flight !!!
rgds
pls check once more yr manuals, for a so called direct law U need
-triple ir fault
-triple prim fail
-two elev fault
-both eng out
in all other failure/law configs U have still protections, in alternate mode the AOA protection is still there. RYFM
Ground mode or direct law for pitch control is till 8 sec after liftoff, from 100 ft down to ground U swap into flare mode, touchdown + 2 sec direct law.
So U R really unhappy when U get >>>direct law<<< in flight !!!
rgds
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Please read once more yr manual before telling somebody such a thing.
There is no direct law in air
There is no direct law in air
A330 and 340 can too. FCOM 1.27.30 FLIGHT CONTROLS - RECONFIGURATION CONTROL LAWS refers, no matter whether it's 320, 330 or 340 manual. Getting into direct law while airborne on TA Airbi is very unlikely yet it's possible.
What's the name of the thread, anyway?
What's the name of the thread, anyway?
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All Fly by wire Airbus airplanes can end up in direct law in flight. On the A320 series it is a bit more common though than on the A330/340 as the architecture of the flight control computers is less sophisticated. On the A320 if you loose both flight augmentation computers (FAC) in flight you revert back into alternate law and upon landing gear extension into direct law. On the A330/340 a simple dual radio altimeter fault will have you ending up in direct law upon landing gear extension when the autopilot is switched OFF, we practice this exercise in the simulator. Low speed and high speed stability on all fly by wire Airbus can be overridden by the pilot and since alpha floor is not available in alternate and direct law the aircraft will stall.
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Read the question before answering...
h3dxb, have you read the title of this thread?
We're talking A320 here, not A330! So no PRIM, no SEC's (and I mean Secondary Flight Control Computer not Spoilers Elevator Computer)...on A320.
It's quite feasible to end in Direct law on A320, and far more unprobable on A330 I admit.
If a failure leads you to fly in alternate law, you WILL end in Direct Law once the gear is down, why? Because there is no Flare law in ALTN law, the only way to flare the aircraft is to put it in Direct law...it has been designed like that.
But again, the related topic is on A320, not A330/340.
Edit: this msg is redondant with ALK's...saw it after.
We're talking A320 here, not A330! So no PRIM, no SEC's (and I mean Secondary Flight Control Computer not Spoilers Elevator Computer)...on A320.
It's quite feasible to end in Direct law on A320, and far more unprobable on A330 I admit.
If a failure leads you to fly in alternate law, you WILL end in Direct Law once the gear is down, why? Because there is no Flare law in ALTN law, the only way to flare the aircraft is to put it in Direct law...it has been designed like that.
But again, the related topic is on A320, not A330/340.
Edit: this msg is redondant with ALK's...saw it after.