B734 aileron ctl prob

[jetrat]

gents, looking for opinions for a situation on a b734

this aircraft has had a history of a particular problem where the aileron does not feel right. i personnally would describe it as a feel very similiar to that of cws. previous reports have been; sluggish, stiff etc. some guys report a certain "dead band". any one out there with an inkling to what i have described. or had similiar experience and have found what caused it......

comments much appreciated

[oreny]

have a good look at the feel and centerung unite spring ' rollers and cams. if all looks normal go for a prper by the book lubrication. if still not same on botth sides you or one of ur people tuched a cable guord ' gromet or cable guide somtime back and only after few flts one noticed the difernt. cable run and close inspection will reville were is the problem. also if the the a/c was lately at basic maintenance a ballance panel seal which is not prperly installed may be the cause. good lock !

[jetrat]

oreny

thanks for your inputs. forgot to mention that i'm not an engineer. but, will speak to one and see what he says. unfortunately i wont get a chance to carry out maintainance work, therefore hoping for some pilots input on how to report. thanks again anyway.

[TechCons]

I tend to agree with Oreny - the feel & centering unit roller has a habit of seizing up or becoming sticky - this can easily produce the symptoms that you have described

[barit1]

How is this described in the AMM Fault Isolation? The symptoms should be in terms that are familiar to the average pilot. :confused:

[jetrat]

barit1

right, will try get a hold of it. unfortunately there's quite a bit of resistance when it comes to pilots trying to get eng. literature in our organisation.
:hmm:

[jetrat]

by the way,

when i flew it the last time, noticed that there the ailerons were not flush with the wing when the trim was at zero. then found that it required up to 1.3-1.4 units of left trim to get it as close to flush as visually possible.

suspect that may have some sort of link to the feel situation, with some trial and error after a total of 4 sectors, did find that it somehow contributed perhaps, by the flight spoilers getting activated when it was not supposed to, causing sluggishness, and not activating when it was supposed to in the other direction, causing the apparent "stiff" feel that was reported as well.

tried leaving the trim at 1.3 to replace the zero datum, and found significant improvement in the aileron control feel. later confirmed on the ground that there was a difference in control column deflection to activate the flight spoilers in opposing directions.(when trims set at 0;which meant actual aileron position wasn't flush)

i now suspect that all this mess could have been caused purely by the "error" between the zero aileron trim setting, and the actual position of the ailerons.
could this scenario happen?

anyone?

[allthatglitters]

I tend to agree with Oreny - the feel & centering unit roller has a habit of seizing up or becoming sticky - this can easily produce the symptoms that you have described

Seizing up or becoming sticky, have seen the outer part of the bearing worn throu with the cam it follows.

[jetrat]

thanks once again.

will definitely storm into the eng. office and BEG for an update. can't tell how long it'll take me to fly the same plane again. so if, it is, the feel centering unit......sticky/seized situation, is it correct to assume that the first indication would be that the control column will not/is reluctant to return to the centre, unless force is applied?

does this situation also cause the control column to be extremely "heavy"?( a lot more force than normal required to move it), when the hydraulics are not pressurised?

lastly, any other possibilities? just curious as hell now........