Vertical Stabilizer Configuration Warning?

[EGLL77W 1,508]

Hey guys-

 

So I experienced this for the first time today too and definitely made me concerned since I knew I had set trim. So I rechecked everything and saw all was set correctly...

 

 

 

Until... I realised I was on the lower end of the trim setting (2.49) and the commanded trim was very much so on the limits. So I changed it to 2.51 and the problem was solved! Doesn't seem like a bug at all. Our trim was simply out of limits if anything below 2.50 units. Better to round up in these scenarios I suppose. I normally get OCD and try to get it exact - but I guess I was feeling lazy today!!

 

 

 

Four engine run-ups for the pax too - those lucky people  :lol: 

[VIPERGTSR01 22]

Yes, reading this for the first time now I was about to bring up exactly what Luke just said above.


A few times I have the trim given to me by the FMC as 2.50 (usually in the low 200's tons), when I adjust for 2.5 I green band is right on the end (I never bother going for exact numbers on the fltctrl page). Sometimes while it looks as set as 2.50 on the trim band it is often a tad less (as shown above on the MFD) and I just tap the trim up once to cancel the warning then proceed again.

[Flamin_Squirrel 71]

I often run into this problem. Surely the green band should be 'higher'?

 

Wait a second. The other day while ground ops was refuelling my plane, I noticed that the CG on the takeoff page changed when I reselected it. Shouldn't that be the zero fuel CG, and should not therefore change with fuel load?

 

I'm not at my desktop for a few days, could someone check? A bug maybe?

[KriVa 307]

I don't think it's the Zero Fuel CG. Why? Because you're setting the indicated trim value for Take-off.

During Take-off, the fuel you loaded will also be a factor as to what trim you should set.

[Flamin_Squirrel 71]

I don't think it's the Zero Fuel CG. Why? Because you're setting the indicated trim value for Take-off.

During Take-off, the fuel you loaded will also be a factor as to what trim you should set.

Yes that's definitely a possibility. The FCOM doesn't confirm either way.

[Speed Of Flight 0]

The "altn trim" levers left of the throttle levers with one click will set trim to a favorable angle, but not the means to properly set pitch or "stabilizer trim". I saw this message "config stabilizer" on takeoff at KBFI, and it will always appear if an incorrect trim value is present. The FMC is the proper place to set exact trim for takeoff, as current TOW and CG will be accounted for. I am still learning this bird, and have noticed that it isn't one that even an accomplished sim pilot can simply jump in and fly. Hope this helps someone.

[AlwynNel 0]

This issue remains unresolved. It only happens to me when I do a short flight, where I have selected "Short Range" on the fuel page in the FS Actions menu. It has nothing to do with the horizontal stabilizer (setting your trim).

 

I have tried to start on the runway, so the were no external input from the control surfaces whatsoever prior to lining up with the runway. As soon as I advance the throttle the warning sounds until I get the V1 callout, then it goes away.

 

However, if I take off on a mid range or long range flight (more fuel onboard), it does not happen. I came to the conclusion this might be a glitch in the coding.

[Ken.Pascoe 1]

"If you feel completely lost, read the manuals" (B.G) :smile:

Cheers,

I believe it's "When all else fails ..." hence many forum posts!

 

Also - what's a Vertical Stabilizer?

Reading back through - is the EICAS message definitely "CONFIG STABLIZER" ?

 

The FMC CoG is referenced to the MAC-TOW (Mean Aerodynamic Chord - Take Off Weight) and in normal line ops is taken directly from the load sheet provided by ground ops and fed into the FMC. From this the calculated Stab Trim Setting (for takeoff) is calculated by the FMC, and the FWD/AFT additional trim segments may or may not display on the stabilizer trim display. The CONFIG STABILIZER message comes up as part of the takeoff configuration check (thrust setting in takeoff range plus other triggers) if the stab trim is not set to within the bounds of the green segment(s).

 

It can be a little finicky and if you're right on the edge of the segment you could generate the warning - is that what we're seeing here?

 

Note that the CoG setting here is also used to determine your maximum altitude. If your cruise CoG is significantly different to your takeoff setting (fuel burnt off) then updating this figure to a more correct number can improve altitude capability.

[dwildkat 12]

I believe it's "When all else fails ..." hence many forum posts!

 

Also - what's a Vertical Stabilizer?

Reading back through - is the EICAS message definitely "CONFIG STABLIZER" ?

 

The FMC CoG is referenced to the MAC-TOW (Mean Aerodynamic Chord - Take Off Weight) and in normal line ops is taken directly from the load sheet provided by ground ops and fed into the FMC. From this the calculated Stab Trim Setting (for takeoff) is calculated by the FMC, and the FWD/AFT additional trim segments may or may not display on the stabilizer trim display. The CONFIG STABILIZER message comes up as part of the takeoff configuration check (thrust setting in takeoff range plus other triggers) if the stab trim is not set to within the bounds of the green segment(s).

 

It can be a little finicky and if you're right on the edge of the segment you could generate the warning - is that what we're seeing here?

 

Note that the CoG setting here is also used to determine your maximum altitude. If your cruise CoG is significantly different to your takeoff setting (fuel burnt off) then updating this figure to a more correct number can improve altitude capability.

 

Ken Its really nice to see your presence here in our simulation Forums. I am a big fan of your website posts.

[kevinh 409]

This issue remains unresolved. It only happens to me when I do a short flight, where I have selected "Short Range" on the fuel page in the FS Actions menu. It has nothing to do with the horizontal stabilizer (setting your trim).

 

I have tried to start on the runway, so the were no external input from the control surfaces whatsoever prior to lining up with the runway. As soon as I advance the throttle the warning sounds until I get the V1 callout, then it goes away.

 

However, if I take off on a mid range or long range flight (more fuel onboard), it does not happen. I came to the conclusion this might be a glitch in the coding.

The warning certainly is related to the horizontal stabiliser. There is no configuration warning for the vertical stabiliser. Making a control input will not change the stabiliser position on ground either, which is the key here. What trim position do you set for these short range flights? Is it within green band limits?

[AlwynNel 0]

The warning certainly is related to the horizontal stabiliser. There is no configuration warning for the vertical stabiliser. Making a control input will not change the stabiliser position on ground either, which is the key here. What trim position do you set for these short range flights? Is it within green band limits?

Fair enough. Problem is I believed the FMC when it told me to set my trim to 2.50 Decided to up it with four increments to 3.50 and the alarm fell silent. Problem solved. Thanks.

[kevinh 409]

Fair enough. Problem is I believed the FMC when it told me to set my trim to 2.50 Decided to up it with four increments to 3.50 and the alarm fell silent. Problem solved. Thanks.

Glad to hear. The 200LR always seem to give a trim position in this forward area. 2.5 units is at the edge of the green band so should be ok. 2.75 would certainly be.

 

I've set 2.5 units and it's been fine, no warning. But if it did warn me I would trim it aft one click.