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Airbus sideslip crosswind

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Airbus sideslip crosswind

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Old 17th Sep 2020, 23:05
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Airbus sideslip crosswind


What about the rudder pedals? Wind from the right and right rudder applied?? That doesn't look good to me. What do you think? This is A330 official type rating training
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Old 18th Sep 2020, 00:20
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Yes, wind from right needs left rudder. I don't think the pictures are all supposed to tell a consistent story. It' just "topic of the day is sideslips! So here's a picture of some rudder pedals, here's a picture of a crosswind..." (Or if they are supposed to be consistent, there were bigger fish to fry than thorough quality control on this slide, and it's a simple mistake.)
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Old 18th Sep 2020, 11:04
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A320 strong crosswind from the right-hand side. Decrab applying left rudder...if the side stick is in the neutral position, the airplane automatically applies some upwind bank angle (rolls to the right) to zero the roll rate induced by the yaw correction. Am I right?



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Old 18th Sep 2020, 14:16
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Originally Posted by mi68guel
A320 strong crosswind from the right-hand side. Decrab applying left rudder...if the side stick is in the neutral position, the airplane automatically applies some upwind bank angle (rolls to the right) to zero the roll rate induced by the yaw correction. Am I right?
Not by applying bank angle but by applying some ailron and may be spoilers it will prevent the roll from the yaw. Also the axis is ahead of C of G so the aircraft swings towards the wind.
​​
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Old 18th Sep 2020, 14:33
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This is the correct picture. Sidestick neutral, when the right rudder is applied to align with the RWY the aircraft AUTOMATICALLY lowers the upwind wing (left one).
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Old 18th Sep 2020, 18:32
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The only thing in this picture that's not necessarily correct it the A/C trajectory.
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Old 18th Sep 2020, 21:08
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After de crabbing the acft trajectory is aligned with the fuselage and the runway track so it looks good to me.
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Old 20th Sep 2020, 06:37
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Originally Posted by mi68guel

This is the correct picture. Sidestick neutral, when the right rudder is applied to align with the RWY the aircraft AUTOMATICALLY lowers the upwind wing (left one).
The answer is in the text at the bottom of your picture: “the lateral controls attempt to zero the roll rate” which means that they try to maintain the current angle of bank. If you want to lower the upwind wing you’ll have to do it yourself. The lateral controls will then attempt to maintain that.
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Old 20th Sep 2020, 09:03
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The text says "sideslip is automatically performed" so with sidestick neutral and rudder applied the sideslip is done automatically by the aircraft applying bank angle opposite to the rudder deflection. Why donīt you try it the next time you go to the SIM?

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Old 20th Sep 2020, 12:18
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Applying steady rudder for a huge crosswind is a dead easy way to land the 320. I used it whenever necessary.
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Old 20th Sep 2020, 13:53
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Originally Posted by mi68guel
The text says "sideslip is automatically performed" so with sidestick neutral and rudder applied the sideslip is done automatically by the aircraft applying bank angle opposite to the rudder deflection. Why donīt you try it the next time you go to the SIM?
With side stick neutral the flight control laws maintain zero rate of roll. It will not bank but prevent the yaw from causing roll. FCTM below:
The recommended de-crab technique is to use all of the following:
‐ The rudder to align the aircraft with the runway heading during the flare
‐ The roll control, if needed, to maintain the aircraft on the runway centerline. Any tendency to drift downwind should be counteracted by an appropriate lateral (roll) input on the sidestick.
In the case of strong crosswind, in the de-crab phase, the PF should be prepared to add small bank angle into the wind in order to maintain the aircraft on the runway centerline. The aircraft may be landed with a partial de-crab (residual crab angle up to about 5 °) to prevent an excessive bank. This technique prevents wingtip/sharklet (or engine nacelle) strike caused by an excessive bank angle.
As a consequence, this may result in touching down with some bank angle into the wind (hence
with the upwind landing gear first).

Last edited by vilas; 20th Sep 2020 at 18:17.
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Old 20th Sep 2020, 21:15
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Just to add to all the wisdom already published a quick read by Airbus.

Truth is no matter how knowledgeable you are, certain manoeuvres require a lot of practice to be mastered and need to be practiced regularly to avoid loosing the “grip”. Those Covid times possibly flying 1 - 2 times a month surely do not help.
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Old 21st Sep 2020, 10:51
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Originally Posted by mi68guel
The text says "sideslip is automatically performed" so with sidestick neutral and rudder applied the sideslip is done automatically by the aircraft applying bank angle opposite to the rudder deflection. Why donīt you try it the next time you go to the SIM?
Correct, with rudder applied but wings level the aircraft will be sideslipping. I teach the FCTM method in the sim as quoted by Vilas in his reply above.
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Old 21st Sep 2020, 13:46
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Originally Posted by mi68guel
The text says "sideslip is automatically performed" so with sidestick neutral and rudder applied the sideslip is done automatically by the aircraft applying bank angle opposite to the rudder deflection. Why donīt you try it the next time you go to the SIM?
Try in the sim autoland with 20kts crosswind. Keep the Flt Ctl page open and it will show you what it does.
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Old 22nd Sep 2020, 07:47
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Smile

Originally Posted by vilas
With side stick neutral the flight control laws maintain zero rate of roll. It will not bank but prevent the yaw from causing roll. FCTM below:
The recommended de-crab technique is to use all of the following:
‐ The rudder to align the aircraft with the runway heading during the flare
‐ The roll control, if needed, to maintain the aircraft on the runway centerline. Any tendency to drift downwind should be counteracted by an appropriate lateral (roll) input on the sidestick.
In the case of strong crosswind, in the de-crab phase, the PF should be prepared to add small bank angle into the wind in order to maintain the aircraft on the runway centerline. The aircraft may be landed with a partial de-crab (residual crab angle up to about 5 °) to prevent an excessive bank. This technique prevents wingtip/sharklet (or engine nacelle) strike caused by an excessive bank angle.
As a consequence, this may result in touching down with some bank angle into the wind (hence
with the upwind landing gear first).
Iīve got an FCTM too and I read it carefully!!
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Old 22nd Sep 2020, 07:50
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Try manual flight, crosswind and press the rudder and tell me were the bank angle goes (sidestick neutral)....
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Old 22nd Sep 2020, 08:06
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Originally Posted by mi68guel
Try manual flight, crosswind and press the rudder and tell me were the bank angle goes (sidestick neutral)....
With stick neutral for rudder application there is supposed to be no bank. The exercise in sim I mentioned is mentioned in Miami airbus Instructors meeting. When OEI demo is given with hands off it only banks 7° to 9° for same reason. It can't keep zero bank because yaw damper doesn't have that much authority.
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Old 22nd Sep 2020, 13:01
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Originally Posted by vilas
With stick neutral for rudder application there is supposed to be no bank. The exercise in sim I mentioned is mentioned in Miami airbus Instructors meeting. When OEI demo is given with hands off it only banks 7° to 9° for same reason. It can't keep zero bank because yaw damper doesn't have that much authority.
If you are a SIM instructor, can you try it there. With all the information I have, I disagree with you, sorry!!
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Old 22nd Sep 2020, 13:09
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Originally Posted by Tail-take-off
The answer is in the text at the bottom of your picture: “the lateral controls attempt to zero the roll rate” which means that they try to maintain the current angle of bank. If you want to lower the upwind wing you’ll have to do it yourself. The lateral controls will then attempt to maintain that.
I donīt understand the picture as you do! The only way to finish this topic is by trying it in the SIM or empty flight. Sidestick neutral , apply rudder and see where the bank angle goes. I say oppositte to the rudder deflection (sidesliping automatically).

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Old 22nd Sep 2020, 13:15
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Originally Posted by Tail-take-off
Correct, with rudder applied but wings level the aircraft will be sideslipping. I teach the FCTM method in the sim as quoted by Vilas in his reply above.
You are mentioning a condition "but wings level" ...This is not the case Iīm talking about. What Iīm saying is: fly wings level, A/P off, apply rudder, and see what happens (bank angle YES/NO which side??). I say R rudder bank angle to the left, L rudder bank angle to the right....
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