From a blog years ago:

“There seems to be some confusion between QNH and QFE creeping into this thread.

QFE is the barometric setting which causes the aircraft altimeter to read zero when the aircraft is on the ground at the aerodrome to which the QFE relates. Aircraft elevations when QFE is set are reported as "height". It is usual - in the UK - to land and take off with QFE set. A few years ago the RAF experimented with the US system where aircraft operated only on QNH (but with QFE available on request).

QNH is the barometric setting which causes the aircraft altimeter to show the aircraft height above sea level. This is the setting usually used for cross country flying below the transition level as it also shows your height above the chart datum. When QNH is set, aircraft elevation is reported as "altitude".

If flying above the transition level (in the UK generally 3,000 feet amsl) pilots flying in accordance with the Instrument Flight Rules are required, and pilots flying VFR are advised, to use QNE. This is a standard setting of 1013.25 hPa. Aircraft elevation is reported as "flight level”.”

 

Jim

 

 

what is a QNH?