ENR 1.6 ATS SURVEILLANCE SERVICES AND PROCEDURES
1.6.1 Primary Radars
1. General
1.1 ATS Surveillance units operate as an integral part of the parent ATS unit and provide surveillance services (radar) to aircraft to the maximum practicable extent to meet operational requirements.
1.2 Factors such as surveillance coverage, controller workload, and equipment capabilities affect these services. The ATS surveillance controller will determine whether radar/surveillance services can be provided or continued in any specific case.
1.3 Within the Damascus FIR, ATS surveillance units provide radar control service and radar information service, as applicable, to the maximum extent practicable.
1.4 Unless otherwise instructed by ATC, position reports may be omitted by aircraft receiving ATS surveillance services.
1.5 Pilots will be advised by ATC on the commencement, identification, and termination of ATS surveillance (radar) services.
2. Application of ATS Surveillance Services
2.1 ATS surveillance services are provided in accordance with ICAO Doc 4444 (PANS-ATM), Chapter 8.
2.2 Radar services within the Damascus FIR are provided by:
- Unit: Damascus Area Control Centre / Damascus Radar Control
- Call Sign: DAMASCUS RADAR
3. RADAR COVERAGE
Total radar coverage within the Damascus FIR.
| Damascus Primary Radars | ||
|---|---|---|
| Location | Type | Max Range (NM) |
| Damascus | PSR | 80 NM |
| Damascus Secondary Radars | ||
|---|---|---|
| Location | Type | Max Range (NM) |
| Damascus | SSR | 200NM |
4. APPLICATION OF RADAR CONTROL SERVICE
4.1 Radar identification is achieved in accordance with the provisions specified in ICAO Doc 4444 (PANS-ATM).
4.2 Radar control service is provided within all controlled airspace. This service may include:
a) Radar separation of arriving, departing, and en-route traffic;
b) Radar monitoring of arriving, departing, and en-route traffic to provide information on any significant deviation from the normal flight path;
c) Radar vectoring, when required;
d) Assistance to aircraft in emergency situations;
e) Assistance to aircraft crossing controlled airspace;
f) Warnings and position information regarding other traffic considered to constitute a hazard;
g) Information to assist in the navigation of aircraft;
h) Information on observed weather phenomena.
4.3 The minimum horizontal radar separations applied are:
a) 20 NM longitudinal separation between aircraft on the same track, at the same level, and maintaining the same speed.
b) 10 NM longitudinal separation for aircraft climbing or descending on the same track.
c) 10 NM lateral separation for aircraft climbing or descending on the same or reciprocal tracks, provided the tracks are not converging.
1.6.2 SECONDARY SURVEILLANCE RADAR (SSR)
1 Operating Procedures
1.1 Except as provided below, pilots shall operate transponders and select modes and codes in accordance with ATC instructions. In particular, when entering the Damascus FIR, pilots who have already received specific instructions from ATC concerning the transponder setting shall maintain that setting until otherwise instructed. Mode C (altitude reporting) shall be selected at all times unless otherwise instructed by ATC or under emergency conditions.
1.2 SSR Code Allocation System:
a) The Damascus Flight Information Region (FIR) operates in accordance with the ICAO Regional SSR Code Allocation Plan (ORCAM).
b) Aircraft entering the Damascus FIR shall retain the SSR code previously assigned by Air Traffic Control (ATC) in the adjacent departure/originating FIR, and shall not change this code except in the following circumstances:
1) When specifically instructed by Damascus Area Control Centre (ACC); or
2) In the event of an emergency (selecting 7500, 7600, or 7700).
c) Transit/Overflight SSR codes (Mode A: 5700 to 5777) will be assigned by Damascus ACC only when an aircraft enters the FIR without a previously allocated code, when code conflicts need to be resolved, or for aircraft departing Damascus FIR to destinations outside the airspace.
d) Domestic SSR codes (Mode A: 3000 to 3777) will be assigned by Damascus ACC for flights operating entirely within the Damascus FIR.
2 Emergency Procedures
2.1 If the pilot of an aircraft encountering a state of emergency has previously been directed by ATC to operate the transponder on a specific code, this code setting shall be maintained until otherwise advised by ATC. In all other emergency circumstances, the transponder shall be set as follows:
a) Mode A/3 Code 7500: Unlawful interference (Hijacking).
b) Mode A/3 Code 7600: Radio communication failure.
c) Mode A/3 Code 7700: Emergency (General emergency).
2.2 Notwithstanding the procedure in paragraph 5.1.1 above, a pilot may select Mode A/3 Code 7500, 7600, or 7700, as appropriate, whenever the nature of the emergency is such that this appears to the pilot to be the most suitable course of action.
3. RADAR AND RADIO FAILURE PROCEDURES
3.1 Radar Failure
3.1.1 In case of radar failure or loss of radar identification, instructions will be issued by ATC to restore non-radar standard separation, and the pilot will be instructed to communicate with the parent ATS unit.
3.2 Radio Failure
3.2.1 Aircraft Not Equipped with a Transponder:
The radar controller will establish whether the aircraft radio receiver is working by instructing the pilot to perform a turn, maintain the new heading for a specified period of time, and then resume normal navigation. The magnitude of the turn will be such as to enable identification to be achieved should the aircraft not previously have been identified. The direction of the turn will be determined by operational requirements.
3.2.2 Aircraft Equipped with a Transponder:
The radar controller will establish whether the aircraft radio receiver is working by instructing the pilot to perform one or more of the following:
a) Change transponder mode;
b) Change transponder code;
c) Operate the SPI feature.
The method used will be such as to enable identification to be achieved should the aircraft not previously have been identified.
3.2.3 Action by Radar Control:
a) If subsequent movement of the radar echo or radar responses indicate that the aircraft radio receiver is working, the radar controller will assume or resume radar control, as the case may be, and continue to pass instructions as for a normal radar service.
b) If subsequent movements of the radar echo or radar responses indicate that the aircraft radio receiver is not working, the radar controller will take action, according to the circumstances prevailing, as detailed in paragraphs 6.2.3 c) and 6.2.3 d) below, as appropriate.
c) If, prior to the communication failure, the radio failure aircraft was identified, the radar controller will ensure that all known traffic is provided with a minimum of 20 NM horizontal radar separation from the radio failure aircraft, performing identification as necessary, until such time as the radio failure aircraft leaves radar coverage or lands.
d) If, prior to the communication failure, the radio failure aircraft was not identified or its position is not known, the radar controller will continue to provide a radar service to identified aircraft only, provided that primary radar coverage is sufficient to ensure a minimum of 20 NM horizontal radar separation from all unknown traffic, until such time as the radio failure aircraft is known to have left the area or landed.
3.2.4 Action by Aircraft:
a) Aircraft able to receive transmissions from radar control will comply with such instructions as are issued, acknowledging as indicated by the radar controller, as detailed in paragraph 6.2.3 a) above.
b) Aircraft not able to receive transmissions will comply with the ICAO radio communication failure procedures as prescribed in Annex 2 (3.6.5.2), Doc 4444 PANS-ATM (Chapter 15.2), and those detailed in specific aerodrome AIP sections (AD 2.OSDI for Damascus International Airport and AD 2.OSAP for Aleppo International Airport).
c) It is essential that the procedures as detailed above are rigidly adhered to, as the actions by radar control are based upon aircraft compliance therewith; failure to comply may result in a loss of separation.
3.2.5 Action in the Event of Air-Ground Communication Failure:
As soon as it is known that two-way communication has failed, ATC shall maintain separation between the aircraft experiencing communication failure and other aircraft based on the assumption that the aircraft will operate in accordance with paragraphs 6.2.6 and 6.2.7.
Note: The following expands upon the requirements contained in ICAO Annex 2 (3.6.5.2) and PANS-ATM (8.8.3 and 15.2) and specifies additional details regarding air-ground communications failure within the Damascus FIR.
3.2.6 Visual Meteorological Conditions (VMC):
Except as provided in paragraph 6.2.7, a controlled flight experiencing communication failure in VMC shall:
a) Set transponder to Code 7600;
b) Continue to fly in VMC;
c) Land at the nearest suitable aerodrome; and
d) Report its arrival time by the most expeditious means to the appropriate air traffic control unit.
3.2.7 Instrument Meteorological Conditions (IMC):
A controlled IFR flight experiencing communication failure in IMC, or in VMC when it does not appear feasible to continue in VMC within the Damascus FIR, shall:
a) Set transponder to Code 7600;
b) Maintain the last assigned speed and level, or the minimum flight altitude if higher than the last assigned level, for a period of 7 minutes. The 7-minute period commences:
1) If operating on a route without compulsory reporting points, or instructed to omit position reports:
i) At the time the last assigned level or minimum flight altitude is reached; or
ii) At the time the aircraft sets the transponder to Code 7600; whichever is later.
2) If operating on a route with compulsory reporting points and no instruction to omit position reports has been received:
i) At the time the last assigned level or minimum flight altitude is reached; or
ii) At the previously reported pilot estimate for the compulsory reporting point; or
iii) At the time the aircraft fails to report its position over a compulsory reporting point; whichever is later.
c) Thereafter, adjust level and speed in accordance with the filed flight plan;
Note 1: With regard to changes to levels and speed, the "filed flight plan" (the flight plan as filed with an ATS unit by the pilot or designated representative without any subsequent changes) will be used.
d) If being radar vectored or proceeding offset according to RNAV without a specified limit, proceed in the most direct manner possible to rejoin the current flight plan route no later than the next significant point, taking into consideration the applicable minimum flight altitude;
Note 2: Concerning the route to be flown or the time to begin descent to the arrival aerodrome, the "current flight plan" (the flight plan including changes brought by subsequent clearances) will be used.
e) Proceed according to the current flight plan to the appropriate designated navigation aid serving the destination aerodrome and, when required to ensure compliance with 3.2.7- hold over this aid until commencement of descent;
f) Commence descent from the navigation aid specified in 3.2.7 e) at, or as close as possible to, the expected approach time (EAT) last received and acknowledged or, if no EAT has been received and acknowledged, at, or as close as possible to, the estimated time of arrival (ETA) resulting from the current flight plan;
g) Complete a normal instrument approach procedure as specified for the designated navigation aid; and
h) Land, if possible, within 30 minutes after the estimated time of arrival specified in 3.2.7 f) or the last acknowledged expected approach time, whichever is later.
Note: Pilots are reminded that the aircraft may not be in an area of secondary surveillance radar coverage throughout the entire Damascus FIR.
3.2.8 Non-Radar Standard Separation / Emergency Separation:
In the event of radar failure or procedural separation application, ATC will maintain the following non-radar separations:
a) Minimum longitudinal separation shall not be less than 20 NM between aircraft at the same level on the same track.
b) Minimum longitudinal separation shall not be less than 20 NM between aircraft on crossing tracks.
c) Minimum longitudinal separation for descending or climbing aircraft on the same route and same track shall not be less than 10 NM at the time the level is crossed.
d) Minimum lateral separation for descending or climbing aircraft on the same route or reciprocal tracks shall not be less than 10 NM provided no tracks are converging.
e) In case of radar failure, the air traffic controller may temporarily apply a minimum vertical separation of 500 FT below FL410, and 1000 FT at or above FL410, between aircraft temporarily until standard non-radar separation can be established.
1.6.3 Automatic dependent Surveillance -Broadcaste (ADS-B)
NIL
1.6.4 Other rel event information and Procedures
NIL
