Airbus sideslip crosswind

[Banana Joe]

I am not rated but the way I understand it is that the F/CTL computers will attempt to mantain present bank angle. Even if you were to cross the threshold with a 10° bank angle and then apply rudder without any sidestick input, the F/CTL computers will apply ailerons and spoilers to attempt to mantain 10° bank angle.
If you're level (0° bank angle), than the wings will be kept level as much as possible: the bank angle goes nowhere. It's 0.

This is coming from someone that was about to change to Airbus and lurked in the books in his free time...

[Vessbot]

Originally Posted by mi68guel

I say R rudder bank angle to the left, L rudder bank angle to the right....

Both the pictures you've posted say that "the lateral controls attempt to zero the roll rate," and nowhere in that does it say that it banks opposite. That is not zero roll rate. Yes it would be revealing to see what happens in the sim, and in all the decades and the countless people that have flown Airbus sims, someone would have probably noticed if it banks opposite.

You're reading too much into the part of the quote that "a sideslip is automatically performed," which is poorly worded and doesn't mean anything. Forget about that. Aerodynamically, sideslip is any time the the relative wind is misaligned from the axis of the airplane when looking from above, aka beta angle is not zero. (Much like thinking about AOA, or alpha angle, when looking from the side). This is only a part of the sideslip (or forwardslip) maneuvers flown in small planes where the plane is cross-controlled so as to create an aerodynamic sideslip while preventing heading change.

[mi68guel]

Originally Posted by Vessbot

and nowhere in that does it say that it banks opposite.

It doesnīt say it because thereīs a picture of an airplane sideslipping with stick in neutral

You're reading too much into the part of the quote that "a sideslip is automatically performed," which is poorly worded and doesn't mean anything.

Iīm not a native English speaker but it looks clear to me. sideslip is an intentional cross control manoeuver in which the pilot has made an aileron input in one direction with a simultaneous rudder input in the opposite direction. In this case, is not the pilot who does. Itīs written that a sideslip is AUTOMATICALLY performed by the plane
Iīm gonna stop answering. Can anybody please try it in the SIM and record it? Thanks

[vilas]

performed by the plane
Iīm gonna stop answering. Can anybody please try it in the SIM and record it? Thanks

A320 doesn't do it. If you try Auto land with crosswind as I mentioned it just keeps wings level by raising aileron and spoilers.

[vilas]

Read Airbus Safety First issue #15

[Vessbot]

Originally Posted by mi68guel

It doesnīt say it because thereīs a picture of an airplane sideslipping with stick in neutral

The picture doesn't mean anything, you're reading too much into that too. It's just a picture of a crosswind landing since the topic of the slide is crosswind landings in general. It doesn't mean that the specific FBW output of the specific control input discussed in the text is what the picture is.

Iīm not a native English speaker but it looks clear to me. sideslip is an intentional cross control manoeuver in which the pilot has made an aileron input in one direction with a simultaneous rudder input in the opposite direction. In this case, is not the pilot who does. Itīs written that a sideslip is AUTOMATICALLY performed by the plane
Iīm gonna stop answering. Can anybody please try it in the SIM and record it? Thanks

Words sometimes have multiple meanings, and this is one of those times. One meaning of "sideslip" is what you said, but as I tried to explain in my last post, there are also others. The meaning referred to in the training slide, is not the one you said.

[Tail-take-off]

Mi68uel
You keep telling everyone to try it in the simulator. Why don’t you do the same? We’re all eagerly awaiting your report on the results!

[neilki]

FBW

Originally Posted by Tail-take-off

Mi68uel
You keep telling everyone to try it in the simulator. Why don’t you do the same? We’re all eagerly awaiting your report on the results!

I for one would love a deep dive technical volume on how Fifi actually works. The current publications are targeted at line pilots; and often those converting from a conventional jet.

The Airbus does use G & Roll Rate, but it also takes into account G Rate. -From memory, CLB modes command different delta G depending on the change in Altitude selected -thats in the FCOM.
Consider a similar situation to the Crosswind discussion; an Engine Failure at 50' in SRS with the AP engaged. The Flight Control Computers are perhaps taken by more of a surprise than the Pilot on a PC (!!) but Fifi gets upset and struggles to correct the roll and yaw for a good couple of seconds. Look at the FLT CTRL page. It's like the LED display on a 90's boombox.
Under manual flight in VMC the maneuver can be performed more smoothly.

The bottom line for crosswinds, just like Airbus says; is the jet is designed to land just like a Boeing. Thats why the ELACs introduce a pitch snapshot then command nose down.
In a strong crosswind, rudder will introduce roll; given a couple of seconds the roll will be corrected; but in the flare at ten feet; we don't have a couple of seconds and the pilot actually has to fly the jet. Bank angle to correct drift et al..
PS. The Airbus does not have a yaw damper. It has a FAC that contains yaw damping functionality, but the FAC sends commands to the Rudder Hydraulics based on what it understands is going on..

[vilas]

[QUOTE] [PS. The Airbus does not have a yaw damper. It has a FAC that contains yaw damping functionality, but the FAC sends commands to the Rudder Hydraulics based on what it understands is going on../QUOTE] Not true at all. Airbus definitely has yaw dampers which work on G and Y hydraulics. If you loose G+Y you have FAC but loose yaw damping. Check FCOM Flt Ctl reconfiguration.

[FlightDetent]

Originally Posted by Banana Joe

If you're level (0° bank angle), than the wings will be kept level as much as possible: the bank angle goes nowhere. It's 0.

This is coming from someone that was about to change to Airbus and lurked in the books in his free time...

Clearly. A qualified instructor would explain on the very beginning that's not what the FBW is capable of. The general heading is there, but zooming from the big picture into real life detail, much livelier attitude is revealed. De-crabbing is a dynamic manoeuvre, mostly in ground effect and flare mode, the usual characteristics of swept wing apply. Pertinently discussed by other contributors.