ENR 1.7  Altimeter setting procedures

1   Introduction

The altimeter setting procedures in use generally conform to those contained in Regulation 923/2012/EU as amended by Regulation 2016/1185/EU and ICAO Doc 8168-OPS/611.
Transition altitudes of all Slovenian airports are depicted on the Instrument Approach Charts.
QNH reports and temperature information for use in determining adequate terrain clearance are provided in MET broadcasts and are available on request from the air traffic services units. QNH and QFE values are given in hectopascals.

2   Basic altimeter setting procedures

2.1   General
Vertical positioning of aircraft when at or below the transition altitude is expressed in terms of altitude, whereas such positioning at or above the transition level is expressed in terms of flight levels. While passing through the transition layer, vertical positioning is expressed in terms of altitude when descending and in terms of flight levels when ascending.
Flight level zero is located at the atmospheric pressure level of 1013.2 hPa. Consecutive flight levels are separated by a pressure interval corresponding to 500 ft (152.4 m) in the standard atmosphere, see ENR 1.7.5
2.2   Take-off and climb
A QNH altimeter setting is made available to aircraft in taxi clearance prior to take-off (QFE on request).
Vertical positioning of aircraft during climb is expressed in terms of altitude until reaching the transition altitude above which vertical positioning is expressed in terms of flight levels.
2.3   Vertical separation - en-route
Transition altitude of LJUBLJANA FIR is at 10500 ft MSL. The vertical separation during en-route flight in LJUBLJANA FIR below 10500 ft MSL, shall be expressed in terms of altitude.
The cruising levels corresponding to the magnetic track to be observed when so required by the Rules of the Air are tabulated in para ENR 1.7.5.
2.4   Approach and landing
A QNH altimeter setting and transition level are made available in the routine approach and landing clearances.
Whatever the altimeter setting used for final approach, all clearances and instructions of Air Traffic Control Services at or below transition altitude will always refer to altitude.
2.5   Missed approach
The relevant portions of ENR and ENR shall be applied in the event of a missed approach.

3   Description of altimeter setting region

For the purpose of checking terrain clearance the local QNH of Ljubljana airport will be used within LJUBLJANA FIR. In the en-route phase within controlled airspace flight levels on standard QNH setting shall be used.

4   Procedures applicable to operators (including pilots)

4.1   Pressure-altitude-derived information - SERA.13010 (a)
When the aircraft carries serviceable Mode C equipment, the pilot shall continuously operate this mode unless otherwise dictated by ATC.
4.2   Flight planning
The levels at which a flight is to be conducted shall be specified in a flight plan:
  1. in terms of flight levels if the flight is to be conducted at or above the transition level, and
  2. in terms of altitudes if the flight is to be conducted in the vicinity of an aerodrome and at or below the transition altitude

5   Tables of cruising levels

The cruising levels to be observed are as follows:
From 000 degrees to 179 degreesFrom 180 degrees to 359 degrees
IFR FlightsVFR FlightsIFR FlightsVFR Flights
(1) Magnetic track, or in polar areas at latitudes higher than 70 degrees and within such extensions to those areas as may be prescribed by the competent authorities, grid tracks as determined by a network of lines parallel to the Greenwich Meridian superimposed on a polar stereographic chart in which the direction towards the North Pole is employed as the Grid North.