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mmakela
04-11-2009, 03:59 AM
Hello, I'd like to ask how calibrating baro works.
When I enter and pass transition level at climb
I should push baro to STD. So does it go to 1013
and stay there until I pull it back to arrival pressure?
I have this problem in my PM cockpit, that in STD pressure
the plane goes up or down when I rotate baro encoder.
This should not happen, right? Thanks!

Preston Brockhurst
04-11-2009, 07:06 AM
I'm not sure about PM (or indeed actual aircraft) but certainly in the FS default aircraft when autoflight is engaged in level flight, if you wind off pressure, you wind off height and the aircraft climbs; vice versa if you wind on pressure you wind on height and the aircraft descends.

In the IFLY 747 whilst STD is selected, you can change the baro setting but it only then becomes active when you click the knob to deselect STD.

You should be on STD when flying at a Flight Level (above Transition Altitude). Crews will select STD when cleared by ATC to climb to a FL. Similarly, they will select QNH when instructed to climb/descend to/ maintain an altitude, usually, as you suggest, on the arrival.

Slightly OT but an interesting site here with relevance to altimeter setting:-

http://www.levelbust.com/

Edit: sorry, I answered this from the main page before realising it was in RW/Airbus forum, hence reference to 747. Hopefully someone with Airbus experience will be able to give you a full answer!

TobiBS
04-11-2009, 05:51 PM
Normally you shouldn't be able to select another QNH while STD is selected, according to FCOM 1.31.50 P1 it has no effect to turn while in STD mode. When pushing it again in descend, you get the last selected QNH and can modify it again.