A320 Gear extension in Alternate law
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A320 Gear extension in Alternate law
I have a doubt about this matter, surely more than one can help please.
Do you configure to Flap 3 and Vapp everytime you are in alternate law (to minimize the use of the man pitch trim) before lowering the gear (hence entering in direct law) ?
Or do you use this technique only in the double hydraulic fault G+Y (no THS)?
If I, as a rule, decided to go F3 and Vapp in any alternate law situation (plus the RA1+2 failure) would it be not always appropriate?
thanx for the input
Do you configure to Flap 3 and Vapp everytime you are in alternate law (to minimize the use of the man pitch trim) before lowering the gear (hence entering in direct law) ?
Or do you use this technique only in the double hydraulic fault G+Y (no THS)?
If I, as a rule, decided to go F3 and Vapp in any alternate law situation (plus the RA1+2 failure) would it be not always appropriate?
thanx for the input
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The current school of thought is that you should configure early regardless of the fact that by dropping the gear it will put you into direct law. The theory is that you get a better feel for trimming when higher on the approach and can be stabilised earlier as opposed to delaying dropping the gear and then potentially wrestling with the aircraft low to the ground.
You would ask ATC for a nice long straight in approach as well to make life easier.
You would ask ATC for a nice long straight in approach as well to make life easier.
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I'll try to answer a bit more precisely to your question.
As far as I know, there is no technical/procedural requirements to follow F1,2,3 then Gear Down in ALTN LAW except for G+Y HYD.
Having said that, it's good practice to follow that sequence in ALTN LAW whenever it's feasible. That's how it's been taught to me in an Airbus course and there are plenty of reasons for that.
A good approach briefing stating your intentions should do it.
As far as I know, there is no technical/procedural requirements to follow F1,2,3 then Gear Down in ALTN LAW except for G+Y HYD.
Having said that, it's good practice to follow that sequence in ALTN LAW whenever it's feasible. That's how it's been taught to me in an Airbus course and there are plenty of reasons for that.
A good approach briefing stating your intentions should do it.
Last edited by shortfuel; 16th Sep 2010 at 17:01.
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except in G+B hyd failure , ast the procedure states . First disconnect the Auto Thrust maintain 200 kts , extend the landing gear then extend your flaps.
Depending on your weight , you might need to select flaps 1 to maintain 200 kts
This procedure is due to the fact that during G+B hyd failure there s only 1 elevator , and this aircraft is very sluggish in pitch . so the idea behind is to maintain enough speed while landing gear is being extended . So if you do it the other way around , the remaining elevator wont be able to counter act properly the pitch down moment created by the gear extension, you will definitely destabilise your approach during landing gear extension .
for All other cases , It might also be a good idea , to familiarise oneself with direct law flying , feel the aircraft , with an early gear extension weather permitting.
has any one of us ever flown the A320 in direct law ? If you delay the landing gear extension you might be surprised , trying to trim it out , something you haven t done for ages , so messing around with the stick close to the ground is not really advisable.
Depending on your weight , you might need to select flaps 1 to maintain 200 kts
This procedure is due to the fact that during G+B hyd failure there s only 1 elevator , and this aircraft is very sluggish in pitch . so the idea behind is to maintain enough speed while landing gear is being extended . So if you do it the other way around , the remaining elevator wont be able to counter act properly the pitch down moment created by the gear extension, you will definitely destabilise your approach during landing gear extension .
for All other cases , It might also be a good idea , to familiarise oneself with direct law flying , feel the aircraft , with an early gear extension weather permitting.
has any one of us ever flown the A320 in direct law ? If you delay the landing gear extension you might be surprised , trying to trim it out , something you haven t done for ages , so messing around with the stick close to the ground is not really advisable.
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Depending on your weight , you might need to select flaps 1 to maintain 200 kts
And selecting the gear around 200 kts is only valid and helpful if at the time of the dual failure, slats were at 0.
But let me rephrase the OP question: he's simply asking if he should follow Flaps 1,2,3 and then Gear down in that order whenever he is in ALTN LAW.
