Visual Flight Rules Guide - © Civil Aviation Safety Authority (E-Text v. 2.6.25)

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TRANSITION LAYER, ALTITUDEANDLEVEL (AIPENR1.7)

Thesystemof altimetryused inAustraliamakesuseof a transition layer between

the transitionaltitudewhich isalways10000 ft and the transition level of FL110

toseparateaircraft usingQNH from thoseusing1013.2HPaasadatum.

For all operationsatorbelow the transitionaltitude, thealtimeter referencewill be:

• the current local QNH of a station along the routewithin 100nm of the

aircraft; or

• the current Area Forecast QNH if the current Local QNH is not known.

For cruising at and above the transition level, theStandardPressure altimeter

settingof 1013.2HPamust be used.

The positions to change betweenQNH and 1013.2HPa are shown in the

diagram below.

QNH is available from a reporting station, theATIS, TAF, AFOR, AERIS or from

ATS. Cruisingwithin the transition layer is not permitted.

3 – general i nformat i on

altimeter setting rules

TRANSITION LAYER

10000

8000

6000

4000

2000

FL110

TRANSITION

LEVEL

TRANSITION

ALTITUDE

Set 1013.2

Prior to transition layer, set Local QNHor, if not available, AreaQNH

Set Local QNH (if available)

Set AreaQNH just prior to topof climb

ALTITUDES - All operations on Local QNHor Area Forecast QNH

NOTE: local QNHof a station along the routewithin 100nmof theaircraft

Set Local QNH if known, otherwiseaerodromeelevation

MSL

FL125

NOTAVAILABLEWHENAREAQNH ISBELOW963HPA

FL120

NOTAVAILABLEWHENAREAQNH ISBELOW980HPA

FL115

NOTAVAILABLEWHENAREAQNH ISBELOW997HPA

FL110

NOTAVAILABLEWHENAREAQNH ISBELOW1013HPA

ALTIMETRY