Rules and Procedures - Altimetry QFE is the barometric altimeter setting that causes an altimeter to read zero when at the reference datum of a particular airfield (in practice, the reference datum is either an airfield center or a runway threshold). In ISA temperature conditions the altimeter will read height above the airfield/runway threshold in the vicinity of the airfield.

The QFE value is given in ATIS broadcasting, QNH shall be communicated to crews by ATS units on crew’s request. The QFE value is indicated in mmHg and in millibars (hPa), QNH value in millibars (hPa).

During the flights within the aerodrome area within a radius of not more than 27NM (50km) from ARP, from take-off till climbing to the transition height and from the transition level till landing the controller shall assign heights in meters based upon the atmospheric pressure at aerodrome (QFE).

The altitude in meters based upon QNH shall be assigned by the controller below the transition level outside the aerodrome area.

Basic Altimeter Setting Procedures

The aircraft position in the vertical plane is determined by height (flight level) and shall be maintained by the crew according to the barometric altimeter taking into account corrections for it.

During the flights at transition level or above the aircraft shall operate a flight according to the indications of the altimeter which is set to atmospheric pressure 760mmHg (1013.2hPa) QNE, during this phase of flight the aircraft position in the vertical plane is expressed in terms of flight levels (flight level/FL).

During the flight at the transition height or below (from take-off till reaching the transition height and from the transition level till landing) the aircraft position in the vertical plane shall be assigned by the controller and reported by the pilots in height values in meters based upon the QFE (height) within the aerodrome area and based upon QNH (altitude) outside the aerodrome area.

A change of flight height (flight level) is allowed by the permission of ATS unit providing service of the aircraft in flight. In this case pilot-in-command must report aircraft position, flight height (flight level) and the reason of its change.

Determination and maintaining of flight height (flight level) shall be based upon:

–pressure at aerodrome - during flights in the aerodrome area within a radius of not more than 27NM (50km) from the ARP (in TMA) from take-off till reaching of transition height and from transition level of the aerodrome (TMA) till landing;

– pressure set to standard atmosphere - at aerodromes approved for international flights and at aerodromes located in mountainous areas (by crew request);

– minimum pressure set to sea level - during flights at altitudes below the lower (safe) flight level (transition level).