What is QNH, QFE and QNE?
The term of Q codes were set of 3 letters begging with a Q to make a clear method of communication. The Q letter basically signifies a question.
*Q Nautical Height (QNH)
Generally, QNH is Q nautical height which means indicating altitude at the height above sea level. Setting on altimeter on the ground, will read the correct elevation above sea level whereby QNH allows displaying the airfield elevation above mean sea level. For example, if the airport which at 900 feet above sea level, the altimeter shall read 900 as well.
Further, QNH also a common setting used during take-off and landing whereby used below the transition level. QNH also known as regional pressure settings because it ensures the aircraft safe terrain separations when cruising at lower altitudes. QNH is given as a regional pressure setting and should be updated with new altimeter setting if leave the area of reference into a new QNH pressure region.
*Q FIELD ELEVATION ( QFE)
Basically, QFE is Q field elevation which means height above airfield. QFE is setting which gets altimeter settings until read zero when on the aerodrome elevation. QFE allows reading height above the runway. For example, during take-off or landing,the QFE reading is “0” when on ground.
Further, when flying to different airfield or QFE pressure, the particular airfield QFE need to reset in order to read zero. The QFE In the circuit, the height indicated is the
height above official airfield datum. For example, If your aerodrome elevation is 800 feet, when the QFE is set on the altimeter, the altimeter should read zero. The thing with QFE is, it changes from aerodrome to aerodrome.
height above official airfield datum. For example, If your aerodrome elevation is 800 feet, when the QFE is set on the altimeter, the altimeter should read zero. The thing with QFE is, it changes from aerodrome to aerodrome.
*QNE ("En Route")
QNE is a pressure setting of 29.92 inches or 1013 hPa that will produce a standard atmosphere altitude and provides the basis for flight levels. The term does not appear to be used by the ICAO, though the concept itself is used to produce flight levels. QNE is explicitly defined in U.S. FAA sources.
*Note
QNH is sea-level pressure. It’s used to cause the altimeter to register height above sea level. When sitting on the ground at an airport, dialing QNH into the altimeter will cause it to display the airport’s altitude above sea level.
QNH is sea-level pressure. It’s used to cause the altimeter to register height above sea level. When sitting on the ground at an airport, dialing QNH into the altimeter will cause it to display the airport’s altitude above sea level.
QFE is air pressure at the current ground level. It’s used to cause the altimeter to register height above the ground (for a certain area). When sitting on the ground at an airport, dialing QFE into the altimeter will cause it to display zero feet.
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