"Jon Rogers" wrote in message
...


So what would be the risk to aviators of the QNH error? Is it
dangerous?


.... not necessarily 'dangerous' in this case, but shows up that there is
a problem with the equipment and / or procedures, which needs sorting
out before it drifts too far. Barometers can drift off calibration and
regular checking is required to make sure that gross errors (which might
become critical) aren't overlooked.

Martin.


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