These supplementary procedures are taken from ICAO Doc 7030 – Supplementary Procedures – and relating to the Mid-Asia Region are given in their entirety. For differences applied in Saudi Arabia, see GEN 1.7 .

These procedures are supplementary to the provisions contained in ICAO Annex 2, Annex 6 (Part II), Annex 11, PANS-ATM (Doc 4444) and PANS-OPS (Doc 8168).

1.8.1 FLIGHT RULES

1.8.1.1 Visual flight rules (VFR)

(relating to Annex 2 - 4.7 and 4.8)

1.8.1.1.1. VFR flights to be operated within a control zone established at an aerodrome serving international flights and in specified portions of the associated terminal control area shall:

have two-way radio communications;
obtain clearance from the appropriate air traffic control unit; and
report positions, as required.

Note : The phrase "specified portionsof the associated terminal control area" is intended to signify at least those portions of the TMA used by international IFR flights in association with approach, holding, departure and noise abatement procedures.

1.8.1.2 Instrument flight rules (IFR)

(Relating to Annex 2 - 2.2 and Chapter 5)

Note : Annex 2, 2.2 permits a choice for a flight to comply with either the instrument flight rules or the visual flight rules when operating in visual meteorological conditions subject to certain limitations in Chapter 4 of the Annex. The following indicates certain further restrictions to that choice.

1.8.1.2.1 Special application of instrument flight rules

1.8.1.2.1.1. Flights shall be conducted in accordance with the Instrument Flight Rules ( even when not operating in instrument meteorological conditions ) when operated:

more than 100 NM seaward from the shoreline within controlled airspace; or
above flight level 150.

1.8.1.3 Air traffic advisory service

(relating to PANS-ATM, Part VI - 1.4)

Note : The PANS-ATM leave it to the discretion of the pilot whether or not to obtain air traffic advisory service when available. The following procedures make it compulsory to obtain such service under certain circumstances.

1.8.1.3.1. All IFR flights shall comply with the procedures for air traffic advisory service when operating in advisory airspace.

1.8.1.4 GLOBAL AIR TO AIR FREQUENCY

VHF frequency 123.45 MHZ introduced by ICAO for use by pilots to exchange operational information. (relating to ICAO ANNEX 10 para 4.1.3.2.1)

1.8.2 FLIGHT PLANS

1.8.2.1 Contents of flight plans

(relating to Annex 2 - 3.3; PANS-ATM, Part II - 8.1 and Appendix 2)

1.8.2.1.1 Mach number

1.8.2.1.1.1. Turbojet aircraft intending to operate within airspace and on air routes to which longitudinal separation minima utilizing Mach number technique will be applied shall include the Mach number planned to be used in Item 15 of the flight plan.

1.8.3 AIR-GROUND COMMUNICATIONS AND INFLIGHT REPORTING

Note : Annex 2. 3.6.3, 3.6.5.1 and 5.3.3 and PANS-ATM, Part II, 14, require controlled flights and certain IFR flights outside controlled airspace to maintain a continuous listening watch on the appropriate radio frequency and to report positions in specified circumstances. The following expands such requirements and specifies additional details regarding the transmission and contents of in-flight reports.

1.8.3.1 Application

(relating to Annex 2 - 3.6.3, 3.6.5, 5.3.3; PANS-ATM, Part II - 14)

1.8.3.1.1. All aircraft on VFR flights, and aircraft on IFR flights outside controlled airspace, shall maintain a watch on a radio station furnishing communications for the unit providing flight information service in the flight information region and file with that station information as to their position unless otherwise authorized by the State overflown.

1.8.3.2 Transmission of position reports

(relating to PANS-ATM, Part II - 14.1)

1.8.3.2.1. The last position report before passing from one flight information region to an adjacent flight information region shall also be made to the ATS unit serving the airspace about to be entered.

1.8.3.2.2. Responsibility for the transmission of position reports to the additional ATS units specified in 3.3.1 may be delegated to the appropriate communications station(s) through local arrangement.

1.8.3.3 Contents of position reports

(relating to PANS-ATM, Part II - 14 and 15)

1.8.3.3.1 Position and time

1.8.3.3.1.1. Position reports shall be identified by the spoken word "position" transmitted immediately before or after the aircraft call sign/identification.

1.8.3.3.1.2. The aircraft call sign / identification shall be transmitted immediately before or after the word "position".

1.8.3.3.1.3. The position of the aircraft shall be transmitted in reference to a reporting point name, name-code designator or, if not named:

for flights operating in a predominantly east-west direction:
1. latitude in degrees and minutes; and
2. longitude in degrees only;
for flights operating in a predominantly north-south direction:
1. latitude in degrees only; and
2. longitude in degrees and minutes.

1.8.3.3.1.4. The time at which the aircraft is over the reporting point shall be transmitted in four digits, giving both the hour and the minutes.

1.8.3.3.1.5. The altitude/flight level of the aircraft shall be included in the position report.

1.8.3.3.2 Next position and time

1.8.3.3.2.1. Next position shall normally be expressed as the reporting point name, name-code designator or latitude and longitude as indicated in 18.3.3.1.3.

1.8.3.3.2.2. Estimated time over next position shall be expressed in four digits.

1.8.3.3.3 Ensuing position

1.8.3.3.3.1. Ensuing position information shall include the name, name code or coordinates of the next succeeding reporting point, whether compulsory or not.

1.8.4 SPECIAL PROCEDURES FOR IN-FLIGHT CONTINGENCIES

1.8.4.1. The following procedures are intended for guidance only. Although all possible contingencies cannot be covered, they provide for cases of inability to maintain assigned level due to weather, aircraft performance, pressurization failure and problems associated with high-level supersonic flight. They are applicable primarily when rapid descent, turnback or both are required. The pilot's judgement shall determine the sequence of action taken, having regard to the specific circumstances.

1.8.4.2 General procedures

The following general procedures apply to both subsonic and supersonic aircraft.

1.8.4.2.1. If an aircraft is unable to continue flight in accordance with its air traffic control clearance, a revised clearance shall, whenever possible, be obtained prior to initiating any action, using the radiotelephony distress or urgency signal as appropriate.

1.8.4.2.2. If prior clearance cannot be obtained, an air traffic control clearance shall be obtained at the earliest possible time and, in the meantime, the aircraft shall broadcast its position (including the ATS route designator or the track code, as appropriate) and intentions, on frequency 121.5 MHZ at suitable intervals until air traffic control clearance is received.

1.8.5 AIR TRAFFIC CONTROL CLEARANCES

1.8.5.1 Adherence to ATC approved route

(relating to Annex 2 - 3.6.2))

1.8.5.1.1. If an aircraft on a long over-water flight has inadvertently deviated from the route specified in its ATC clearance, it shall forthwith take action to regain such route within 200 NM from the position at which the deviation was observed.

1.8.5.2 Adherence to ATC approved Mach number

(Relating to Annex 2 - 3.6.2)

1.8.5.2.1. Turbojet aircraft intending to operate within airspace and on air routes to which longitudinal separation minima utilizing Mach number technique will be applied shall adhere to the Mach number approved by ATC and shall request ATC approval before making any change thereto. If essential to make an immediate temporary change in Mach number (e.g. due to turbulence), air traffic control shall be notified as soon as possible that such a change has been made.

1.8.5.2.2. If it is not feasible, for operational reasons, to maintain the last assigned Mach number, pilots of aircraft concerned shall advise ATC at the time of initial clearance or subsequent climb/descent request or clearance.

1.8.6 USE OF SECONDARY SURVEILLANCE RADAR (SSR)

(PANS-ATM, Part X and PANS-OPS, Vol. I, Part VIII)

1.8.6.1 Application of procedures

Note : Some military aircraft are required to operate Identification – Friend or Foe (IFF) transponders for non-air traffic control purposes simultaneously with and independently of their operation in Mode A for air traffic control purposes.

1.8.6.1.1 Operation of transponders

1.8.6.1.1.1. When it is necessary to stop IFF/SIF transponders from replying on Mode A/3, pilots shall be requested to switch off Mode 3 (see 7.3.1, "STOP SQUAWK THREE"). In no case shall they be requested to switch to STANDBY, since operation of the STANDBY switch stops the IFF/SIF transponders from replying on all modes.

1.8.6.1.2 Operation of SSR equipment and displays

1.8.6.1.2.1. SSR derived information shall be checked by use of special monitoring devices, or by correlation of an identified primary radar blip with the appropriate SSR response.

1.8.6.1.2.2. The "all codes" setting shall be used when it is desired to display for air traffic control purposes all aircraft in a specified area that are equipped with SSR or IFF/SIF transponders; the "all aircraft" setting shall be used when it is desired to display also aircraft equipped with basic IFF transponders.

1.8.6.1.3 Assignment of SSR codes

1.8.6.1.3.1. Regardless of the SSR capability of the ATS units concerned, an aircraft engaged in international flight shall be assigned an appropriate four-digit code by the area control centre/ flight information centre at the beginning of the flight, if it is to be conducted under the instrument flight rules. The code shall be assigned from within the code block(s) in Table ATS-3 of the MID/ ASIA Air Navigation Plan (Doc 8700) allocated to the area control centre/flight information centre of the originating information region and shall be retained and used by the aircraft until its arrival at destination, with modifications as provided for in 1.8.6.1.3.2 below.

1.8.6.1.3.2 Flight in two-digit code environments or non SSR areas

Departing from a two-digit code environment . The aircraft shall be assigned a four-digit code, but the code shall not be issued to the aircraft. Instead, a two-digit code shall be issued according to local procedures. The assigned four-digit code shall be issued when the aircraft reaches a predetermined point after passing through the two-digit code environment.
Traversing a two-digit code environment . The aircraft shall transpond on the assigned four-digit code until it reaches a predetermined point where it shall be instructed to change to the required two-digit code. After passing through the area, the area control centre concerned shall instruct the aircraft to revert to the previously assigned four-digit code.
Landing in a two-digit code environment . The aircraft shall be instructed to change to a two-digit code as required by the responsible area control centre.
Traversing non-SSR areas or landing in non-SSR areas . The area control center/flight information center will include the assigned four-digit code as a part of the transfer message.
Departing from a non-SSR area . The aircraft shall be assigned a four-digit code upon departure, and the area control flight/flight information flight shall include the code in the departure and transfer messages.

1.8.6.1.3.3 Forwarding of the assigned code to ATS units enroute and at destination

1.8.6.1.3.3.1. The ATS unit serving the aerodrome where the flight originates shall include the assigned four-digit code in the departure message sent to each addressee of the flight plan.

1.8.6.1.3.3.2. The area control flight/flight information flight serving the flight information region where the flight originates shall include the assigned four-digit code in the transfer message to the next area control flight/flight information flight. The area control centers/flight information centers of subsequent flight information regions over flown by the aircraft concerned shall ensure that the code is included in the transfer-messages.

Note : This is particularly important in the case of 1.8.6.1.3.2).

1.8.6.2 Use of SSR-derived information for the provision of separation between aircraft

1.8.6.2.1. Except when the positional element of an SSR response cannot be resolved [see Note following 1.8.6.2.1)], SSRderived information may be used alone for the provision of horizontal separation between aircraft in the circumstances and under the conditions specified below:

Within the coverage area of the associated primary radar, in order to overcome known deficiencies of that radar, e.g. the fact that primary radar echoes of certain aircraft are not, or not continuously, presented on the radar display due to the reflecting characteristics of such aircraft, clutter, etc. In this case, SSR responses may be used for the separation of transponderequipped aircraft and, additionally, for the separation of transponder-equipped aircraft from other known aircraft not using SSR but displayed clearly on the primary radar display, provided that the SSR response from any aircraft (not necessarily the one being provided separation) coincides with the primary radar echo of the same aircraft.

Note : Where SSR accuracy cannot be verified by means of monitor equipment or by visual correlation of the SSR response with the primary radar echo from a given aircraft, SSR responses alone may be used only to provide identification.
Outside the coverage area of the associated primary radar provided that:
1. there is an agreed need to provide radar control service in that portion of the airspace covered by SSR, but beyond the coverage of the associated primary radar;
2. the aircraft concerned have previously been identified and identification has been maintained;
3. only procedural separation is applied between aircraft with functioning transponders and other aircraft;
4. the SSR coverage is known.
In defined areas where advanced ATS systems are in operation and SSR is the main source for the provision to air traffic services of continuous information on the position of aircraft, and where the carriage of SSR transponders is mandatory, the appropriate ATS authority, after consultation with operators, may authorize the systematic provision of horizontal and/or vertical separation, based on SSR-derived information, between aircraft which are equipped with correctly functioning transponders, provided that:
1. adequate SSR coverage exists throughout the area wherein this procedure is used, and reliable operation of this service is assured;
2. identification of individual aircraft so separated is maintained by means of discrete codes;
3. adequate primary radar or SSR ground equipment backup is provided or, alternatively, in case of SSR failure, density and/or complexity of air traffic in the area, and the availability of navigational guidance allow to revert safely to other forms of separation (based on either the use of primary radar or procedural control).
  
  Note : where appropriate forms of separation should be applied between aircraft with functioning transponders and other controlled aircraft.
when primary radar fails and until procedural separation is established, provided that:
1. the positional accuracy of the SSR responses has been verified (see 1.8.6.2.1) and Note);
2. the pilots of the aircraft concerned have been advised.
in the case of aircraft in emergency.

Note : Apart from causes resulting in the inability to resolve the positional element of an SSR response which can occur due to malfunctioning of the equipment, there are two causes which may occur during normal operations. These are the presence of side-lobe responses and reflections.

1.8.6.2.2. The separation minima used should not be less than those applied when using the associated primary radar, if any, on the understanding that the resolution of the SSR is not better than that normally associated with primary radar.

1.8.6.3 Phraseology

(PANS-ATM, Part X - 6.3)

1.8.6.3.1 Phrase Meaning

SQUAWK LOW - Turn master control to "low" sensitivity position, retaining present mode and code.
SQUAWK NORMAL - Turn master control to "normal" position, retaining present mode and code.
STOP SQUAWK THREE - Switch off Mode 3.
This phrase is reserved for use with military aircraft only.

*SQUAWK LOW - Turn master control to "low" sensitivity position, retaining present mode and code. *SQUAWK NORMAL - Turn master control to "normal" position, retaining present mode and code. *STOP SQUAWK THREE - Switch off Mode 3. * This phrase is reserved for use with military aircraft only.

1.8.7 SPECIAL PROCEDURES APPLICABLE IN DESIGNATED AIRSPACES

1.8.7.1 Use of composite routes

1.8.7.1.1. When composite separation is used in accordance with the following procedures apply:

An aircraft may be cleared to join an outer route of the system at other than the normal entry point provided:
1. Longitudinal or non-composite vertical separation exists between that aircraft and any other on that route; and
2. composite separation exists between that aircraft and any other on the next adjacent route.
An aircraft may be cleared to leave an outer route of the system at other than the normal exit point provided its course diverges so that the lateral spacing from the route increases until longitudinal or non-composite lateral, or non-composite vertical separation exists between that aircraft and any other aircraft in the system.
An aircraft may be cleared to change from one route to an adjacent route in the system provided:
1. longitudinal or non-composite vertical separation exists between that aircraft and any other aircraft on the route being vacated until that aircraft is established on the route to which it is proceeding;
2. longitudinal or non-composite vertical separation exists between that aircraft and any other aircraft on the route to which that aircraft is proceeding; and
3. composite separation exists between that aircraft and any other aircraft on the next adjacent route.
An aircraft may be cleared to cross the system provided longitudinal or non-composite lateral or non-composite vertical separation exists between that aircraft and any other aircraft in the system.
An aircraft may be cleared to change altitude on a route if longitudinal or non-composite vertical separation exists between that aircraft and any other aircraft on that route and regardless of any other aircraft on adjacent routes.

Note : Non-composite separation referred to above is separation in accordance with the minima in 1.8.6.1.1 and 1.8.6.2.1 and those in the PANS-ATM, Part III, 3.1.

1.8.8 ALTIMETER SETTING PROCEDURES APPLICABLE TO AIR TRAFFIC SERVICES AND MINIMUM LEVELS

(Relating to PANS-ATM, Part II - 12 and Part III - 4.2)

1.8.8.1. The lowest usable flight level for holding and approach manoeuvres shall be calculated from actual QNH, unless the pressure variation is so small that reference to climatological data is acceptable.

Note 1 : The lowest usable flight level will provide a terrain clearance of at least 300 M (1 000 FT), and, for operation in the vicinity of an aerodrome, will not be established below 450 M (1 500 FT) above aerodrome elevation.

Note 2 : MET Offices will inform ATS units when, in abnormal conditions, pressure would go below the minimum climatological value, in order that appropriate steps be taken to cancel temporarily the use of the lowest flight level or levels which would not ensure the minimum terrain clearance.

1.8.8.2. Based on current and anticipated atmospheric pressure distribution, area control centers shall coordinate, where required, the lowest flight level to be used.

1.8.9 FLIGHT INFORMATION SERVICE

1.8.9.1 Information on runway conditions

(Relating to Annex 11 - 4.2.1; PANS-ATM, Part IV - 15.1)

1.8.9.1.1. Unless otherwise provided, area control centers shall have available for transmission to aircraft on request, immediately prior to descent, information on the prevailing runway conditions at the aerodrome of intended landing.

1.8.9.2 Transmission of SIGMET information

(Relating to PANS-ATM, PART VI - 1.3.2)

1.8.9.2.1. SIGMET information shall be transmitted to aircraft with the least possible delay on the initiative of the appropriate ATS unit, by the preferred method of directed transmission followed by acknowledgment, or by a general call when the number of aircraft would render the preferred method impracticable.

1.8.9.2.2. SIGMET information passed to aircraft shall cover a portion of the route up to two hours' flying time ahead of the aircraft.

1.8.9.3 Transmission of amended aerodrome forecast

(Relating to PANS-ATM, Part VI - 1.3.3.2)

1.8.9.3.1. Amended aerodrome forecasts shall be passed to aircraft within 60 minutes from the aerodrome of destination, unless the information would have been made available through other means.

1.8.10 AIR TRAFFIC SERVICES CO-ORDINATION

1.8.10.1 Co-ordination between units providing area 45 control services

(Relating to PANS-ATM, Part VII - 3.2)

1.8.10.1.1. If a flight should enter an adjacent area, information concerning any revision of estimate of three minutes or more shall be forwarded to the adjacent area control flight normally by telephone.

1.8.11 ALERTING AND SEARCH AND RESCUE 45 SERVICES

1.8.11.1 Routes and equipment of private aircraft

Related to ICAO Annex 6 - Part II - 6.3 and 6.4)

1.8.11.1.1. General aviation aircraft operating over designated areas, land or sea, where search and rescue operations would be difficult, should:

carry appropriate survival equipment;
follow the routes or specified procedures if not equipped with two-way radio, except that under special circumstances, the appropriate authority may grant specific exemptions from this requirement.

1.8.11.2 Alerting services

(Relating to PANS-ATM, Part VI - 2)

1.8.11.2.1. The procedures for "Alerting Service" detailed in the PANS-ATM, Part VI, 2, are applicable to all flights except those conducted wholly in the vicinity of an aerodrome when exempted by the appropriate air traffic control unit.

ENR 1.8 REGIONAL SUPPLEMENTARY PROCEDURES