2.1 GENERAL
A transition altitude is specified as 10000
FT above
MSL.
Vertical positioning of aircraft when at or below 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 trough 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 (29.92 in). Consecutive flight levels are separated by pressure interval corresponding to 500
FT (152.4
M) in the standard atmosphere.
Note: Examples of relationship between flight levels and altimeter indications are given in the following table, the metric equivalents being approximate:
2.2 TAKE-OF AND CLIMB
A
QNH altimeter setting is made available to aircraft as a part of departure information.
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 EN-ROUTE
Vertical separation
Vertical separation during en-route shall be expressed in terms of flight levels or altitudes when flying below transition altitude.
On
VFR flights, at and below the transition altitude, the pilot shall set altimeter to
QNH to the vale of controlled aerodrome nearest to the route of flight exceeds the vicinity of the departure aerodrome.
IFR flights, and
VFR flights above 3 000
FT (900
M) operating in cruising flight in controlled airspace shall be flown at a cruising level, or, if authorized to employ cruise climb techniques, between two levels or above a level selected from the Table of cruising levels specified in Annex 2, Appendix 3, a).
Except that correlation of levels to track prescribed therein shall not apply whenever otherwise indicated in air traffic control clearance or specified in the AIP.
As specified in the ICAO EUR Regional Supplementary Procedures (Doc 7030/4 – EUR), flights shall be conducted in accordance with Instrument Flight Rules when operated within or above the EUR RVSM airspace.
Terrain clearance
For the purpose of adequate terrain altitude clearance local
QNH based upon aerodromes Banja Luka, Mostar, Sarajevo and Tuzla are to be used depending on the terminal control area in which the flight is conducted.
A
QNH altimeter setting necessary for flight planning or terrain clearance shall be passed by approach control service, on request.
2.4 APPROACH AND LANDING
A
QNH altimeter setting is made available by competent
ATC Unit, not later than passing transition level or together with the clearance to enter controlled airspace.
A
QFE altimeter setting are normally not available at controlled aerodromes, except for flights within a
CTR, upon request and
ATC approval.
Vertical positioning of aircraft during approach is controlled by reference to flight levels until reaching the transition level below which vertical positioning is controlled by reference to altitudes.