A320 Low speed stability
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That's it!!
Flare mode only effects the pitch control. When L/G down (in alternate law), this will revert to direct stick-to-elevator relationship (DIRECT MODE)
However. there is an exception, when in alternate law due to the abnormal attitude laws. In this case there is no reversion to direct law at landing gear extension, as everything is working properly.
Flare mode only effects the pitch control. When L/G down (in alternate law), this will revert to direct stick-to-elevator relationship (DIRECT MODE)
However. there is an exception, when in alternate law due to the abnormal attitude laws. In this case there is no reversion to direct law at landing gear extension, as everything is working properly.
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Here's a quiz question for everyone....
Can the A-320 series Airbus be stalled in flight in normal law? If so, under
what conditions/circumstances?
The answer can be found in the FCOM.....
Fly safe,
PantLoad
what conditions/circumstances?
The answer can be found in the FCOM.....
Fly safe,
PantLoad
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Out of memory (so no precise ref.):
In "appropriate" conditions (i.e. high angle of attack, severe loss of energy...) + :
- normal law + autothrust inop
- ...EPR Control Mode Fault (IAE engines)
- One Engine Inoperative with S>0
Basically all conditions in normal law leading to a loss of Alpha Floor function or part of it (thrust part for instance here).
Any reference for that? 
In "appropriate" conditions (i.e. high angle of attack, severe loss of energy...) + :
- normal law + autothrust inop
- ...EPR Control Mode Fault (IAE engines)
- One Engine Inoperative with S>0
Basically all conditions in normal law leading to a loss of Alpha Floor function or part of it (thrust part for instance here).
However. there is an exception, when in alternate law due to the abnormal attitude laws. In this case there is no reversion to direct law at landing gear extension, as everything is working properly.
Last edited by shortfuel; 30th Mar 2009 at 20:18.
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Do you Airbus jockeys find it difficult to keep aware of how the aircraft will try and perform in certain abnormal situations i.e. when the control laws change and in different phases of flight? As a non-Airbus pilot I get the impression that it would be very easy to lose track of exactly what the aircraft capabilities/protections/responses/etc. will be with degraded control logic.
Genuine question.
B&S
Genuine question.
B&S
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Even the intellegency of such a wonderful European creation, sometimes causes questions. My dear B&S. Don't worry to much about it.
FCOM 1.27.30 Abnormal attitude laws
You are still having your AoA protection, meaning you won't exceed alpha max, even with sidestick fully aft.
Quote:
However. there is an exception, when in alternate law due to the abnormal attitude laws. In this case there is no reversion to direct law at landing gear extension, as everything is working properly.
Any reference for that?
However. there is an exception, when in alternate law due to the abnormal attitude laws. In this case there is no reversion to direct law at landing gear extension, as everything is working properly.
Any reference for that?
Out of memory (so no precise ref.):
In "appropriate" conditions (i.e. high angle of attack, severe loss of energy...) + :
- normal law + autothrust inop
- ...EPR Control Mode Fault (IAE engines)
- One Engine Inoperative with S>0
Basically all conditions in normal law leading to a loss of Aplha Floor function or part of it (thrust part for instance here).
In "appropriate" conditions (i.e. high angle of attack, severe loss of energy...) + :
- normal law + autothrust inop
- ...EPR Control Mode Fault (IAE engines)
- One Engine Inoperative with S>0
Basically all conditions in normal law leading to a loss of Aplha Floor function or part of it (thrust part for instance here).
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B&S, you don't really "feel" the transition from one law to another, except the direct of course, where it is a little instable and small correction on the stick cause stronger inputs, some sort of a sporty aerobatic plane in level flight.
You only know that you changed laws by looking at the warnings and cautions you get on the ECAMs. Most of the time you come out of the sim and the instructor says "that was now alternate" and you say, uh, that's why. But you don't have a big red lamp on your dashboard where it says "ludicrous law now".
So everything is pretty much straight forward and doesn't need any special intellectual or haptic challenges. One point on the "Golden rules of Airbus flying" says "an Airbus behaves like any other aircraft", and so it is.
Dani
You only know that you changed laws by looking at the warnings and cautions you get on the ECAMs. Most of the time you come out of the sim and the instructor says "that was now alternate" and you say, uh, that's why. But you don't have a big red lamp on your dashboard where it says "ludicrous law now".
So everything is pretty much straight forward and doesn't need any special intellectual or haptic challenges. One point on the "Golden rules of Airbus flying" says "an Airbus behaves like any other aircraft", and so it is.
Dani
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Thanks for the ref. Zonnair, never spotted that one! Never wanna get close to it.
So you think, this A/C cannot stall in quoted conditions just thanks to the remaining AoA prot.
If you get the chance, in a sim, on a final:
CONF Full, Gear down, Fail the A/THR and request significant negative W/S, see what happens...
So you think, this A/C cannot stall in quoted conditions just thanks to the remaining AoA prot.
If you get the chance, in a sim, on a final:
CONF Full, Gear down, Fail the A/THR and request significant negative W/S, see what happens...
What happens is pilot hits toga, follows SRS even if it requires full back stick and survives the sim scenario. Emphasis being on "pilot".
Dear certain PPRuNers, you are mixing up alpha floor and alpha prot. Despite both having "alpha" in their names, they're quite different animals. Alpha prot is function of FBW that limits AoA, alpha floor is automatic setting of TOGA thrust regardless of power levers position. As long as normal law is alive and kicking, alpha prot is available, but alpha floor can be deactivated through autothrust deactivation (this is not mere disconnection). The horror scenario described in the previous post may end up in aeroplane hitting the ground (or trees) at very high angle of attack and engines at idle, but it can not end up in stall. And I don't merely think that fully operational A320 can't stall due to alpha prot - that it can't is a fact and not an opinion.
Dear certain PPRuNers, you are mixing up alpha floor and alpha prot. Despite both having "alpha" in their names, they're quite different animals. Alpha prot is function of FBW that limits AoA, alpha floor is automatic setting of TOGA thrust regardless of power levers position. As long as normal law is alive and kicking, alpha prot is available, but alpha floor can be deactivated through autothrust deactivation (this is not mere disconnection). The horror scenario described in the previous post may end up in aeroplane hitting the ground (or trees) at very high angle of attack and engines at idle, but it can not end up in stall. And I don't merely think that fully operational A320 can't stall due to alpha prot - that it can't is a fact and not an opinion.
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At alpha max (AoA protection) you will go down, if no additional power is added. But going down does not mean stall. Alpha floor has indeed nothing to do with this. It is just another feature that prevent the a/c from stalling, but only when A/THR is operational.
Conclusion indeed is: In normal law you will have AoA protection that will prevent the a/c from excessive AoA (stalling). This does not mean it prevent it from descending or from being slammed into the ground due to WS, or whatever senario you would like to create. For that you still need pilots input.
Conclusion indeed is: In normal law you will have AoA protection that will prevent the a/c from excessive AoA (stalling). This does not mean it prevent it from descending or from being slammed into the ground due to WS, or whatever senario you would like to create. For that you still need pilots input.
