Altitude Difference Problem.

[JRBarrett 3,070]

In an actual aircraft, when the "odd man out" altimeter reads significantly lower than the other two, this would indicate either a malfunctioning ADIRU, or a blockage in the associated static system. (A blocked pitot tube would affect primarily airspeed). If it happens only when the aircraft is pressurized, it would indicate that there is a leak in the static line at some point within the pressurized part of the fuselage. (In either case the associated airspeed indicator would read low too). Either PMDG has implemented a blockage/leakage failure mode for the pitot-static system, (or ADIRU which has lost its calibration), or there is something corrupted in your installation. If you've tried clearing all failures without success, then it's probably the latter...

[BraytonCycle 0]

Is your settings on FSX set to "US metric systems"? If not, try that and make sure your Display Control Panel is "NORMAL".

[oneill875 1]

Pete, Sorry about the "read the manual" advice, just can't tell somebody's experience easily (especially when using an iphone!). Sounds like most option have been covered, maybe a fresh install or a support ticket is in order? I take it that you switched off service based failures in an attempt to localize the problem? Also did you go through all the failure /maint options, including FSX? You probably have, I can't think what it is...... Dan.

[Flexman 30]

Which of the altimeters is closest to field elevation when set to QNH? I forgot to ask, because you might actually be within limitations, at which phase of a flight are you when you find the difference?The allowed inflight difference for RVSM between CAPT and FO is 200ft.

[oneill875 1]

According to the OP the difference was between 50 and 220ft. This varied with the pressure.

[bluepilot76 0]

As already mentioned I think this is the altimeter settings in FSX. There are 3 options, check them out. Happened to me already. If it is a simulated fault, you can go into the PMDG menu and see which faults are current. But I dont think there will be any..

[IanB 0]

x3, as mentioned...Is your settings on FSX set to "US metric systems"? If not, try that and make sure your Display Control Panel is "NORMAL".

[cuirassier 0]

Brayton and Ian Just checked the settings in FSX and you're absolutely on the money. As soon as I changed to Hybrid or US ft and inches it came back to 'normal' supply across the board.Must admit I don't know how it came to be in metric but it sure as heck aint now. Many thanks to all contributors,and as my first time on ANY forum I am really impressed with the help offered. Pete

[Vollie 11]

Is this maybe a NGX failure??......tube outside is blocked??