Airbus A320 roll control.

[chillpill]

New to the Airbus A320 having been on Boeing Jets for years to date! The 'bus' seems like a great a/c in many ways but I am 'interested' in how the experienced A320 drivers out there handle succesfully gusty and strong cross wind approaches and landings!

So far, I have noted that it actually runs out of roll control at times!... ie: even having given the FBW 'zero roll rate' a chance to sort things out and then applying side-stick up to 'full', it still on occasion keeps rolling against these inputs the wrong way!

Not very confidence inspiring near the ground when one is trying to land the beast (scarebus!!??)...

Comments and suggestions please

Thanks muchly!

[el #]

Hi,

before others can contribute with "real deal" type of advice, I can indicate you the "official" answer:

http://www.airbus.com/store/mm_repository/safety_library_items/att00007639/media_object_file_FLT_OPS-LAND-SEQ05.pdf

Sorry if you have this doc already.

[Chris Scott]

Hi chillpill,

We had a rather long discussion re this subject on PPRuNe earlier this year, on a thread "LH A320 Rough Landing @ Hamburg". You could have a look at it if you're not short of time! Here's a link to one of my own contributions, for what it's worth:
http://www.pprune.org/tech-log/316096-lh-a320-rough-landing-hamburg-24.html#post3979423

[TO MEMO]

Chris Scott,

:D:D:D:D:D:D:D:D:D:D:D

Chillpill,

Welcome to the bus!!! You`ll love it! I also flew the 737 several years before flying the A320! Just forget the 737! Both airplanes are very good and a joy to fly! But they fly different! Some prefer the boeing way, some the Bus way (like me!)... The A320 is a magnificent plane!
Learn it well and take advantage of it! The table, the quiet cockpit, the simple procedures, the automation, the sidestick, etc...

Read Chris Scott post, it says it all!

I don`t remember of ever reaching the sidestick stop! Remember, if you reach it, you`re not flying it as you should!

Use the force of your fingers to fly the plane, not the force of your arm, or even your wrist, as many people wrongly do!

When you`re moving the sidestick from one side to the other, just let it go for 2 senconds and then start flying it again making only small inputs!

Cheers!

[dream747]

Airbusdriver.net (http://www.airbusdriver.net/)

This is a great website on the Airbus!

[Dream Land]

So far, I have noted that it actually runs out of roll control at times!This should not happen unless you are operating under the most extreme conditions, like Funchal etc., once you have a little time in the bus you won't want to leave it, good luck.

D.L.

[chillpill]

Many thx guys for the links and info. Good reading.

Read all pages of the Hamburg incident... there seems to indeed be a degree of mis-understanding about how the Flight Control Logic works!

I have no probs with the 'nudging the stick' principle... It indeed works a treat. The question arose on a gusty cross wind day, but within a/c limits! after watching the a/c roll left and continue to do so with no apparant correction. So, give it a bit of a nudge, still rolls left, so a bit more and more smooth right sidestick, but STILL rolling left. Finally end up on the stop, with it still rolling left! Finally begins to roll right and then no probs!

I just never experienced this lack of roll control authority on the Boeing, even in much stronger cross winds! I dont think I ever got to full control column deflection... yet there it was on the A320!

So, it does seem that de-crab in the flare is the way to go, instead of at 100 ish feet then wing down. It is just what to do on the way down that has me writing this after the above experience... And again it was not THAT bad a day!!!

Looking fwd to more 'practice'!!!

[fantom]

TO MEMO,

"I don`t remember of ever reaching the sidestick stop! Remember, if you reach it, you`re not flying it as you should!"

Rubbish.

Wait until you have sixteen years on the magnificent Airbus.

You CAN run out of lateral authority in extreme conditions and it has nothing to do with your flying technique.

I look forward to reading your apology after your first fright.

[Dream Land]

Wait until you have sixteen years on the magnificent Airbus.

You CAN run out of lateral authority in extreme conditions and it has nothing to do with your flying technique.Well there are some pilots that can accomplish this on a calm day but I won't get into that, after ten years on the bus I totally agree with fantom.

[TopBunk]

So, it does seem that de-crab in the flare is the way to go, instead of at 100 ish feet then wing down.

ABSOLUTELY. Do not consider using wing down technique from 100ft:eek: The Flight Control logic would fight you all the way with that technique imho. Squeezing off the drift in the flare is the way forward, and I found nudging (and releasing) the into winf aileron at he same time as squeezing on the rudder pedal worked nicely, leaving the Flight Control logic giving about 1deg wing down in the into wind direction. After touchdown when in direct law, resume normal procedures and 'fly the wing' with into wind aileron as on any other aircraft.

[TO MEMO]

fantom,

I do respect your opinion... after all 16 years is a lot! I`ll be honest with you, I`m flying the bus for 3 years.

You CAN run out of lateral authority in extreme conditions and it has nothing to do with your flying technique.

I look forward to reading your apology after your first fright.

I don`t remember of ever reaching the sidestick stop! Remember, if you reach it, you`re not flying it as you should!

With this I ment that we pilots, should keep this quote in our mental debriefing after each landing. I didn`t mean that pilot flying technique was the fault. If you understood it like that, I do apologize!

I do have fewer hours than you, but with litle over 2000 hours on the 320, I have come to conclusion that 1/3 of stick displacement gave me the same result as full stick, with half the turbulence (ended up realizing that I was creating that turbulence). The 737 was flown quite more agressivelly than the A320. That`s one of the things I love on the plane, I fly it more relaxed than the 37.

But that`s me... 3 years on the plane, not 16... so who nows...

Cheers

[fantom]

Sorry, that was a bit rude of me.

The normal law (as you know) filters inputs and presents a 'soft' reaction.

In adverse conditions this law can be a little slower to react than you might expect, hence running out of authority. If we always approached in direct law, we would not notice the effect.

Be aware: one day you will get my message and I hope to have forewarned you.

Best wishes,

f.

[Clandestino]

I'm absolutely puzzled.

A320 is slow to pick up a dropped wing by itself, but with full stick deflection in normal law, it will try to give you 15 deg/sec roll and it will do it without hesitation and with as much aileron and spoiler deflection as needed. So if you have gradually fed stick up to full, with all ELACs, SECs, control surfaces and hyd operative, then your "scarebus" was rolling against full deflection of ailerons and all four roll spoilers in conditions that were not
THAT bad.

Spoooooky!

Oh and sideslip is easy to do on A320, as long as you remember to let the stick go. But it's useless above 15kt because you run out of bank, and decrab is a piece of cake, so who needs the sideslip, anyway?

[el #]

Isn't this type of problem worth a detailed entry and a through inspection, including looking at FDR ?
After all, if it an a/c doesn't do what is commanded to, there must be a reason,
Perhaps just new software needed in a/c :)

These questions obviously come from an enthusiast that appreciates very much this forum competence, kindness and sporadic nostalgia.

EDIT: after some thinking I got the feeling the most likely is that when the airbus does like that all what one has to do is the" right action" as trained by the ones who know and keep flying happily.
You can happily ignore my naive questions !