ENR 1.7  ALTIMETER SETTING PROCEDURES

1.7.1  Introduction

1.7.1.1 The Altimeter Setting Procedures in the Kuala Lumpur FIR and Kota Kinabalu FIR generally conform to ICAO practices.
1.7.1.2 In co-ordination with the ATS authorities of Malaysia, Singapore and Brunei, a common transition altitude of 11000 ft (3350 meters) and transition level of FL 130 has been established in the Kuala Lumpur FIR, Kota Kinabalu FIR and Singapore FIRs, except for an area of 10 NM centred at Mt. Kinabalu (in the Kota Kinabalu FIR) where the lowest safe altitude is 15000 ft (4570 meters) and the lowest safe level is FL 170.
1.7.1.3 The maximum variation in QNH values in the Kuala Lumpur FIR, Kota Kinabalu FIR and Singapore FIRs is not more than 10 hPa either side of 1013.2 hPa, therefore change of altimeter setting from QNH to 1013.2 represents an indicated change of not more than 300 ft on the altimeter. To simplify ATC procedures, a uniform transition level of FL 130 is established, thus providing a transition layer of 2000 ft, and ensuring at all times a 1000 ft vertical separation between aircraft.
1.7.1.4 Aircraft shall not flight plan to cruise at levels 115, 120 and 125 when operating in Kuala Lumpur FIR and Kota Kinabalu FIR.
1.7.1.5 Flight Level zero is located at the atmospheric pressure level of 1013.2 hPa (29.92 ins). Consecutive flight levels are separated by a pressure level corresponding to 500 ft in the Standard Atmosphere.
1.7.1.6  Area QNH Zones (AQZ)

A common Area QNH will be issued for all the Area QNH Zones defined below:

  1. Kuala Lumpur AQZ - within the airspace in the Kuala Lumpur FIR.

  2. Kota Kinabalu AQZ - within the airspace in the Kota Kinabalu FIR.

  3. Singapore AQZ - within the airspace in the Singapore FIR.

1.7.1.7  Area QNH
1.7.1.7.1 Area QNH is the forecast value of the lowest mean sea level pressure within the AQZ, valid for a period of 6 hours.
1.7.1.7.2 Area QNH as defined above, is one of the types of meteorological data required for the determination of the lowest flight level which will ensure adequate terrain clearance at any location within the AQZ during the period of validity.
1.7.1.7.3 Amendments are issued by Met when the mean sea level pressure at any location in the AQZ is expected to fall below the current Area QNH by more than 2 hPa, and units responsible for the airspace in which the aircraft could be operating on Area QNH shall broadcast the amended value on all air/ground frequencies in use.

1.7.2  Basic Altimeter Setting Procedures

1.7.2.1  Altimeter Setting Procedures
1.7.2.1.1 For flight at or below the transition altitude, the altimeter reference will be Local QNH/Area QNH. Flight will therefore be conducted in altitudes.
1.7.2.1.2 Change from Local QNH (set for departure) to the Area QNH will be made on leaving the TMA/CTR/ATZ after take-off.
1.7.2.1.3 From Area QNH to Local QNH will be made on entry at TMA/CTR/ATZ or on commencement of final approach to land.
1.7.2.1.4 Aircraft transiting through TMA/CTR/ATZ at or below the transition altitude will change to the local QNH on entering the TMA/CTR/ATZ boundaries and to Area QNH on leaving the boundaries.
1.7.2.1.5 Vertical displacement of aircraft climbing through the transition layer is expressed in terms of flight levels and when descending through the transition layer is expressed in terms of altitudes.
1.7.2.1.6 For flight at and above the transition level, the standard altimeter setting of 1013.2 hPa will be used.
1.7.2.1.7 Change from Local QNH/Area QNH to 1013.2 hPa will be made on climbing through the transition altitude.
1.7.2.1.8 Change from 1013.2 hPa to Local QNH/Area QNH will be made on descending through the transition level.
1.7.2.1.9 Cruising within the transition layer is not permitted unless specifically cleared by the Area Control Centre of that FIR.
1.7.2.1.10  Special Procedures for the Kuala Lumpur Terminal Area (TMA)
1.7.2.1.10.1 Aircraft arriving the KL International / Sepang and the Subang/Sultan Abdul Aziz Shah or aircraft transiting the Kuala Lumpur TMA will be given a common QNH setting when cleared to descend, or to transit the TMA below the transition level which is FL130. The common QNH setting will be the QNH for the KL International / Sepang.
1.7.2.1.10.2 Aircraft landing at the Subang/Sultan Abdul Aziz Shah will be provided with the SAAS airport Subang QNH by Lumpur Radar when they have been cleared to final approach.
1.7.2.1.10.3 Aircraft departing the KL International / Sepang and the Subang/Sultan Abdul Aziz Shah will be provided with a common QNH that will be the QNH for the KL International / Sepang.

Note: The QNH difference between the two airports will be negligible.

1.7.2.2  Take-Off And Climb
1.7.2.2.1 Where ATIS is not available, a local QNH altimeter setting shall be made available together with the Area QNH to aircraft by Approach/ Aerodrome Control in the routine take-off and climb instructions.
1.7.2.2.2 A QFE altimeter setting will be made available on request but reports to ATC shall be made in altitudes.
1.7.2.3  Vertical Separation - En-Route
1.7.2.3.1 It is the pilot’s responsibility to select a flight level/altitude which will give adequate terrain clearance using forecast pressure information.
1.7.2.3.2 For the purposes of en-route vertical separation, IFR and VFR flights within controlled airspace and flights in uncontrolled airspace of the Kuala Lumpur FIR and Kota Kinabalu FIR, reference should be made to the following:
  1. Semi-circular system of cruising levels within all controlled airspace (IFR flights);

    (See Table A)

  2. VFR flights - cruising levels within controlled airspace;

    (See Table B)

  3. Cruising levels in uncontrolled airspace;

    (See Table C)

1.7.2.4  Approach And Landing
1.7.2.4.1 Where ATIS is not available, a Local QNH altimeter setting shall be made available in the routine approach and landing instruction.
1.7.2.4.2 A QFE altimeter setting will be made available on request but reports to ATC are to made in altitude.
1.7.2.4.3 Vertical displacement of aircraft during approach is effected by reference to flight levels until reaching the transition level below which vertical displacement is controlled by reference to altitude.
1.7.2.4.4 Change from Area QNH to Local QNH will be made on entry at TMA/CTR/ATZ or on commencement of final approach to land.

1.7.3  Procedures Applicable To Operators And Pilots

1.7.3.1  Flight Planning
1.7.3.1.1 The level(s) 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.

  2. In terms of flight altitudes; if the flight is to be conducted in the vicinity of an Aerodrome and at or below the transition altitude or en-route aircraft transiting at or below the transition altitude in the Kuala Lumpur FIR and Kota Kinabalu FIR.

    Note 1: Short flights in the vicinity of an aerodrome may often be conducted only at altitudes at or below the transition altitude.

    Note 2: Flight levels are specified in a plan by a number, and not in terms of feet as is the case of altitudes.

    Note 3: No aircraft shall flight plan to cruise at levels 115, 120 and 125 when operating in the Kuala Lumpur FIR and Kota Kinabalu FIR.

1.7.4  Semi-Circular System Of Cruising Levels Within The Kuala Lumpur And Kota Kinabalu FIRs

1.7.4.1 The pilot-in-command of an IFR flight at or above 3000 ft within controlled airspace and above FL 250 in uncontrolled airspace shall select a level corresponding to the appropriate magnetic track as indicated in Table A. The Quadrantal Rule as contained in Table C will continue to be used for all flights below FL 250 in uncontrolled airspace of the Kuala Lumpur FIR and Kota Kinabalu FIR.
1.7.4.2 FL 250 in uncontrolled airspace will be held vacant to serve as a buffer.

IFR Flights - Cruising Levels within the Kuala Lumpur FIR and Kota Kinabalu FIR.

TABLE A

Magnetic TrackFrom 000° through East to 179° (feet)From 180° through West to 359° (feet)

Cruising Altitudes

(Local QNH/Area QNH)

3 000

5 000

7 000

9 000

11 000

4 000

6 000

8 000

10 000

Cruising Flight Levels

(1013.2 HPa)

130

150

170

190

210

230

250*

270

290

310

330

350

370

390

410

450

140

160

180

200

220

240

260

280

300

320

340

360

380

400

430

Note:

  1. FL 115, 120 and 125 are not available for use as cruising within the transition layer is not permitted. FL 250 in uncontrolled airspace will be held vacant to serve as a buffer.

  2. To maintain a buffer of 1000 ft between aircraft operating within and outside controlled airspace, aircraft shall not operate closer than 500 ft vertically from the lower limit of controlled airspace.

1.7.4.3 The pilot-in-command of a VFR flight up to FL 150 within Controlled Airspace shall select a level corresponding to the appropriate magnetic track as indicated in Table B. VFR flights shall, however, be conducted subject to ATC approval and shall not be operated by day above FL 150 in all Controlled Airspace and Advisory Areas.

VFR Flights - Cruising Levels up to FL 150 within Controlled Airspace.

TABLE B

Magnetic TrackFrom 000° through East to 179° (feet)From 180° through West to 359° (feet)

Cruising Altitudes

(Local QNH/Area QNH)

1 500

3 500

5 500

7 500

9 500

2 500

4 500

6 500

8 500

10 500

Cruising Flight Levels

(1013.2 HPa)

135

145

Note:

  1. FL 115, 120 and 125 are not available for use as cruising within the transition layer is not permitted.

  2. To maintain a buffer of 1000 ft between aircraft operating within and outside of Controlled Airspace, aircraft shall not operate closer than 500 ft vertically from the lower limit of controlled airspace.

1.7.4.3.1 VFR flights shall NOT be operated by day above FL 150 within controlled airspace and advisory areas.

Flights in uncontrolled airspace above FL 150 may be conducted under VFR.

1.7.5  Quandrantal Cruising Levels In Uncontrolled Airspace of Kuala Lumpur And Kota Kinabalu FIRs Below FL250

1.7.5.1 The pilot-in-command of a VFR or IFR flight at or above 3000 ft outside controlled airspace and below FL 250 shall select a level corresponding to the appropriate magnetic track as indicated in the following Quadrantal Cruising Levels.

TABLE C

Magnetic TracksFrom 000° - 089° (feet)From 090° - 179° (feet)From 180° - 269° (feet)From 270° - 359° (feet)

Cruising Altitudes

(Local QNH/Area QNH)

3 000

5 000

7 000

9 000

11 000

3 500

5 500

7 500

9 500

4 000

6 000

8 000

10 000

4 500

6 500

8 500

10 500

Cruising Flight Level

(1013.2 HPa)

130

150

170

190

210

230

135

155

175

195

215

235

140

160

180

200

220

240

145

165

185

205

225

245

Note:

  1. FL 115, 120 and 125 are not available for use as cruising within the transition layer is not permitted.

  2. To maintain a buffer of 1000 ft between aircraft operating within and outside of controlled airspace, aircraft shall not operate closer than 500 ft vertically from the lower limit of controlled airspace.

1.7.5.2 If compliance with VFR cannot be maintained at a quadrantal cruising level, the aircraft shall be flown at another quadrantal level where it is possible to comply with VFR.
1.7.5.3 The pilot-in-command shall ensure that the cruising level selected for an IFR flight is not below the lowest safe flight level applicable for the route to be flown.
1.7.5.4 Except when taking-off or landing, or with the approval of the appropriate authority, aircraft shall be flown at least 1000 ft above the highest obstacle within 5 NM of the estimated position of the aircraft in flight.

1.7.6  Transit Procedures

1.7.6.1 The procedures to be followed by aircraft when transiting between areas where the Quadrantal System of cruising levels is in use and those where the Semi-Circular System is applicable, are indicated below.
1.7.6.1.1 Transition from the Quadrantal System to the Semi-Circular System.
TRACK FLOWNVFR FLIGHTIFR FLIGHT

000°- 089°

090° - 179°

180° - 269°

270° - 359°

Climb to next ODD + 500 ft level

Maintain ODD + 500 ft level

Climb to next EVEN + 500 ft level

Maintain EVEN + 500 ft level

Maintain ODD level

Descend to next ODD level

Maintain EVEN level

Descend to next EVEN level

1.7.6.1.2 Transition from the Semi-Circular System to the Quadrantal System.
TRACK FLOWNVFR FLIGHTIFR FLIGHT

000°- 089°

090° - 179°

180° - 269°

270° - 359°

Descend to next ODD level

Maintain ODD + 500 ft level

Descend to next EVEN level

Maintain EVEN + 500 ft level

Maintain ODD level

Climb to next ODD + 500 ft level

Maintain EVEN level

Climb to next EVEN + 500 ft level

Note: The terms 'ODD + 500 ft' level and 'EVEN + 500 ft' level have been used to designate those series of levels where, below FL 290, flight levels ending with 75, 95, 115, etc and 65, 85, 105, etc respectively are prescribed.

1.7.7  Changing Levels

1.7.7.1 An aircraft may be required to change level at a time, place, or rate specified by ATC. The pilot-in-command must commence a change of level as soon as possible but not later than 1 minute after receiving that instruction from ATC, unless that instruction specifies a later time or place.

Note: In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft, pilots of aircraft commencing a climb or descent in accordance with an ATC Clearance should inform the controller if they anticipate that their rate of climb or descent during the level change will be less than 500FT per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500FT per minute.

1.7.7.2 When required, the pilot-in-command may be instructed to reach an assigned level by a specified time or position. The pilot-in-command shall advise ATC immediately if he is doubtful whether the assigned level can be reached as instructed.
1.7.7.3 A pilot-in-command shall report:
  1. At the time of leaving a level for a newly assigned level;

  2. When leaving or passing through such other levels as may be specified by ATC; and

  3. On reaching an assigned level.

1.7.7.4 In order to reduce the risk of TCAS RAs, vertical speed should be reduced to a maximum of 1500FT per minute and ideally to between 1000FT per minute and 500FT per minute when in RVSM airspace or within the last 1000FT before cleared level.