QFE

QFE is a three letter acronym which can have meanings in aviation, in software development, and in internet usage.

Aviation acronym

QFE is a Q code used by pilots and air traffic control (ATC) to refer to the barometric altimeter setting which will cause an altimeter to read height above the official reference datum for a particular airfield (generally the height of a particular runway threshold). An altimeter set to QFE will therefore read zero when on the ground at the beginning of the runway. It can be thought of as the QNH for a particular airfield. A mnemonic for the code is "Q Field Elevation".

ATC will update pilots with the QFE when necessary. A typical radio conversation might go:

• Pilot: Golf Whiskey Alpha Charlie Foxtrot, requesting taxi clearance for local VFR.
• ATC: Golf Charlie Foxtrot, taxi to Alpha for two-five right hand, QFE niner-niner-eight millibars.
• Pilot: To Alpha, two-five right, QFE niner-niner-eight, Golf Charlie Foxtrot.

Here, the pilot of G-WACF (who is on the ground) requests a taxi clearance and is told to taxi to holding point A for runway 25, the circuit is right-handed and QFE is 998 millibars. The pilot acknowledges the information by repeating it back to ATC.

In most parts of the world, QFE is given in millibars (or hectopascals, which is the same-sized SI unit). Whilst the Royal Air Force (RAF) and some European private pilots still use QFE, it is largely obsolete in commercial aviation, where QNH is preferred for take off and landing (and where sophisticated radio aids can be used during landing). In general aviation, QFE is routinely used during take off and landing (where the eyeball tends to be used) and when flying in the circuit. The exception to this is in the USA and Canada, where QFE is rarely used, the most common practice being to use QNH (known simply as the "altimeter setting") for all operations below the transition altitude.

Software development acronym

QFE stands for Quick Fix Engineering. This is the Microsoft term for a 'Bug patch' or as it was previously known, a 'Hotfix'. Many software modules related to Microsoft products return a QFE number indicating a patch number in the version/build information. QFE's are often bundled together to make a 'Service Pack'.

Internet acronym

QFE is also a popularly used internet forum acronym for "quoted for emphasis".