PPRuNe Forums - View Single Post - Airfield QNH - what's the point?
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Old 9th Jul 2012, 21:31
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RTN11
 
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IFR traffic only uses QHN with a good knowledge of airfield elevation and MSA, however a visual circuit will likely be based on QFE.

If anything they could do away with QFE and then visual traffic would have to be more aware of airfield elevation.

Regional QNH is something completely different again. An airfield QNH is based on the pressure MEASURED at that airfield, and will be very accurate so when you touch down you will have airfield elevation indicated. Regional QNH is the lowest FORECAST pressure for a region, giving a worst case terrain clearance based on altitude.
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