A340 question for those who fly them

[checkessential]

On the ground the FBW computers will allow a linear deflection of the ailerons and elevators according to the pilot input. Assuming the pilots used a crosswind correction technique to keep the wings level, this would explain the deflection on the takeoff roll. Once the aircraft became airborne, the FBW system goes into C* or the airbus equivalent of normal law. This is why the ailerons "snapped" back to a more correct deflection for the commanded roll rate, which was significantly less than the linear sidestick deflection vs. aileron position. In addition, the sidestick input was probably decreased by the pilot as the airspeed increased, and near zero at rotation. As is the technique on any other plain-jane aircraft.

 

[Tref]

What's the difference between a new Airbus pilot and an old Airbus pilot?

A new Airbus pilot says "what's it doing now?" And an old Airbus pilot says "oh $hit! It's doing that again!"

 

[rumpletumbler]

checkessential,

If you will read my original post you will see that they didn't move from full deflection until the point of rotation, I further clarifed this during yet another post when someone else had missed it. After saying this twice I didn't think I needed to disclaim it but let me go ahead. Excuse me this is making me so sleepy. The ailerons were at full deflection from taxi through takeoff until the point of rotation. At the point of rotation they snapped into a neutral position. There was no gradual decrease, there was nothing gradual about it. Does snapped sound gradual to you?

PS: Just in case anyone has missed the above point that has now been stated on 3 different occasions I'd just like to clarify once again the ailerons were at full deflection from taxi through takeoff until the point of rotation. At the point of rotation they snapped into a neutral position.

PSS: The ailerons were at full deflection from taxi through takeoff until the point of rotation. At the point of rotation they snapped into a neutral position.

If your reading this post and haven't bothered to read the others I'd like to say the ailerons were at full deflection from taxi through takeoff until the point of rotation. At the point of rotation they snapped into a neutral position.

Please take a break before you respond to this post. Then re-read it 100 times. Then re-read all the other posts in the thread. Then write the following on a piece of paper:

The ailerons were at full deflection from taxi through takeoff until the point of rotation. At the point of rotation they snapped into a neutral position.

Thanks.

Now, you may respond to the post.

Yet another disclaimer follows. Someone will be smart enough to go back and say that they saw that I didn't see the other aileron and see that I'm using ailerons in my sentences and will point that out. "Holding up a fish for you and making a barking seal noise" the reason I say this since the one on my side was deflected up I would assume the other to be deflected down as this would indicate to me that it wasn't being used as a lift device.

RT

 

[Vik]

Hey RT,

Don't get your panties in a bunch. You seem to be getting way to excited over a small issue.

 

[rumpletumbler]

Vik,

I don't wear panties. I'm not excited, however, I do get irritated with having to state the same thing over and over and over because what was there already wasn't read. Speaking of accuracy in assesing a situation be it a post, an emergency, determing the gender of a poster, etc. What was it that made you think I wore panties? I mean Vik could be short for Victoria or Vikie or maybe Victor ,however, I don't even after looking at your profile have a clue as to your gender. Perhaps you meant that I might be a man or woman wearing panties. Remember for the purpose of accuracy I can't relate to or understand what your saying unless I have actually worn panties and they have gotten in a wad while I was wearing them. Of course the chances of this happening would be far greater if I were female which I am not. What does all this mean? It means the same thing that the post you are commenting on means. Accuracy and being informed is important in replying to a post. Now don't think I'm sitting here stoneface serious typing this cause I am.

RT

 

[checkessential]

What is the problem? Are you sure that it was the ailerons you were looking at? Were the roll spoilers deployed? Could you see both wings? Please excuse my inattention to particular detail which you yourself forgot to include. I didn't realize this was so serious......

 

[rumpletumbler]

At 08-01-2002 09:19 I posted the following in this thread:

No I didn't see the other wing.

At 08-02-2002 13:15 I posted the following in this thread:

Someone will be smart enough to go back and say that they saw that I didn't see the other aileron.

This what I mean by having to repeat things. I'm not trying to offend you and am not angry etc. It would be my preference though that someone actually read a thread before responding to it. It isn't that serious. Remember it can be hard to know someones frame of mind from reading e-mail, posts, etc. Especially with me. I should be more carefull.

As for them being ailerons if they were spoilers they were the largest spoilers I've ever seen by a big stretch. It was a large control surface and in the same position you would expect it to be for an aileron.

RT

 

[checkessential]

You pose a good question. Most likely the ailerons were acting in tandem to provide a load alleviation function, or the aileron computers calculate a minimum drag position for the takeoff based on CG and weight. I don't really know jack about the a340, so I'll look for the answer too....

 

[Vik]

RT,

I dont take this message board that seriously. It was a joke. You just seemed to be on the verge of having a stroke so I figured a little humor might be in order.

 

[bigD]

rt - I'm just trying to get a sense of what happened here...so the ailerons gradually moved back into a neautral position as the plane was taking the runway, right? And you said you saw the aileron on the other wing deflected the other way too? I'd guess the PF just had some correction in for the taxi. What exactly is the problem, and why are you so worked up?





And yes, I'm laughing as I write this!