PSS B772LR - Lateral Trim

[Guest melf12]

Had a 'strange' experience this morning. On a flight to Larnaca after reaching Cruise Flight Level, I noticed that the Port wing was about 3/4 degrees up (aircraft tilted to the right)? The wind was 241/50 aircraft Hdg 087, not unusual and the T7 should handle that and more, there was slight 'crabbing' again that is normal.I could not find anyway to trim the ailerons, is there such a feature on the T7? So I decided to carry on with the flight, then as I approached the TOD, dump fuel from the starboard tanks, I dumped appx 3 tonnes but at first didn't notice any change. But during the descent, and around 6000' the wings levelled! Apart from crabbing, due to a fairly strong cross wing, we touched down as normal.After that nice little story :) a question - is there a means of lateral trimming on the T7?Ken

[jc_150 3]

Hi KenOn the t7, when you open the radio panel, at the bottom there is aileron trim and rudder trim. when i operate the rudder trim on the ground I can see the rudder trim value change on the display panel flight control display, but on the ground doing the same with aileron trim does not change the position of the aileron positions on the flight control display. Not sure if it should, or what affect this would have in the air, as I do not have the t7 ready for flight right now, but could be worth a go.best regardsJohn Calleja

[FOD 23]

Ken,A quick answer - yes. The aileron trim switches work correctly. Problem is that the indication - see on the VC yoke - seems not to be modelled.John R

[Guest melf12]

Hello John C, I've got the power on (not started the engines). So far as the Rudder is concerned the trim does change value; the Ailerons don't move, I'll check it out tomorrow after I get the engines running. I had seen those controls, but never tried to use them as I thought they came under the 'Not modeled' list :) - well spotted.I'll get back to you tomorrow when i have tested the system.On my flight EGLL to LCLK today it was just normal attitude again?Ken

[Guest melf12]

Hi John R, sorry I didn't see your reply until I answered John Calleja.I don't use the VC type, but I just had a look at it, certainly the button on the yoke looks non-functional. As JC points out, those Rudder/Aileron controls at the bottom of the Radio stack do look more interesting.I'll have a test flight tommorrow, I've just been ordered to the kitchen :)Ken

[FOD 23]

Ken,I flew earlier on to check and you can control the aircraft in roll on the aileron trim switches - but not something to be recommended. Problem is I have never had an out-of-trim situation in the 777 so never had to use them before.Not having a position indicator is a pain although not too much of a problem if you if you trimmimg out an out of trim force on the stick.I suspect that your problem on the first post was something different - a steady one degree of bank does not sound like only an aileron trim problem. Were you in AP?John R

[Guest melf12]

Hello John, when you did your check did you have the AP off; in my check it was on...so obviously there was no reaction from ailerons or rudder. So in my first post it would not have sorted the problem.Incidently, the bank was an umcomfortable 3/4 degrees :) - the next day I made the same flight and the trim was perfect throughout; so we can conclude the OOT flight was a one off. On the bright side it did bring out my 'ingeniuous' side :), also started my quest for a means to adjust ailerons trim; between we have sorted that.Thank you John, "I love it, when a plan comes together" :) Ken

[FOD 23]

Hi Ken,I had to have the AP off - as you say manual trim does not work with AP engaged. The AP should maintain all axes in trim throughout the flight regime.Guess your problem was more likely a display "glitch". Glad its gone.John