Can't change QNH with 'Baroset' dial

[martinlest2 58]

Another little issue. I have noticed that on descent, the QNH value gets 'stuck'. No matter how I try to change it, with the dial or pressing /pulling the 'Baroset' knob - the numbers try to change for a fraction of a second but they jump back immediately to whatever the value they are stuck at. It may be that they  sometimes 'stuck' at the correct value (today yes, but yesterday no, the QNH I couldn't change was very wrong), but whatever, I have never flown a plane where the pilot cannot change the QNH setting even so. Is this a 'feature' of the MD-11?

 

Thanks for comments and a 'fix' if appropriate!

[martinlest2 58]

Hmmm, if anyone knows how this works? It's unlike any other a/c I have flown.

 

My QNH sticks on one value the whole flight and I cannot change it manually. When I get to FL180 or whatever transition altitude is, the only way I can get 29.92 is to switch to QFE. Not even sure what the difference is to be frank (but I can Google that).

 

Also, the Barometer set button never responds to my 'pulling' or 'pushing' it. Ti set STD I have to go to QFE, as I say, then use the outer ring.

 

Do others have the same thing? Or can you change your pressure setting at will in QNH mode?

[scandinavian13 5,192]

 

 

Do others have the same thing? Or can you change your pressure setting at will in QNH mode?

 

Sounds like something is interacting, or you're not doing something correctly.

 

Have you flown the tutorial flight? MD aircraft are a mix of Boeing and Airbus theory, so the buttonology is similarly odd.

[martinlest2 58]

Hi. Yes, I did the London to Zurich flight. To be honest I haven't worked out the barometer dial on this a/c at all - it seems to have a mind of its own compared to all other a/c I have (like the PMDG 747). It locks up and then half an hour it's unlocked, then locked again - I can't get it to change between STD and local pressure .. For now I am just having to 'go with the flow' and adjust QNH/QFE as and when the dial allows me.

 

Again, as per your reply re. HDG/TRK, I tend to think I may be expecting this to behave like, say, the 747, but it doesn't at all. I need to have another trawl through the pdf manuals to see if I can find an explanation...