ENR 1.6 Radar services and procedures

1.6.1. Primary radar
1.6.1.1 Services
  1. Radar units in the EMIRATES FIR operate as integral parts of the ATS system and provide radar control service and radar information service as applicable to the maximum extent practicable.

  2. Unless otherwise requested by ATC, position reports may be omitted when receiving radar service.

1.6.1.2 Application of radar control service
  1. Radar is used for the provision of Air Traffic Services in accordance with ICAO Doc 4444 PANS - ATM, Chapter 8.

  2. Radar services are provided by the units listed below within their areas of responsibility as outlined in GEN 3.3:

    1. Emirates Area Control Centre
    2. Abu Dhabi Approach
    3. Dubai Approach
    4. Fujairah Approach
    5. Ras Al Khaimah Radar
1.6.1.3 Radio and radar failure procedures
  1. In case of communication failure aircraft shall conform to the procedures specified in Annex 2, Chapter 3, para. 3.6.5.2,

  2. Following unsuccessful attempts to established RTF contact, aircraft equipped with satellite and / or mobile telephones shall attempt to contact:

    Under the control ofTelephone number
    EMIRATES AREA CONTROL CENTRE+971 2 599 6969
    ABU DHABI APPROACH or ABU DHABI TOWER+971 2 575 7340
    AL AIN TOWER+971 3 785 5301
    DUBAI APPROACH+971 4 813 3579
  3. For designated holding fixes, refer to table ENR 3.6

1.6.1.4 Radar coverage is provided throughout the FIR. Maximum ranges of the primary radars used for air traffic services are:
UAE Primary Radars
LocationTypeMax Range (NM)
AL AINTAR80
DUBAITAR80
1.6.2. Secondary Surveillance Radar (SSR)
1.6.2.1 Operating procedures
  1. To ensure the safe and efficient use of SSR, pilots and controllers shall strictly adhere to published operating procedures and standard radiotelephony phraseology shall be used. The correct setting of transponder codes and/or aircraft identification shall be ensured at all times.
  2. Aircraft are required to operate SSR transponders in accordance with ICAO Doc 8168 - OPS, Volume 1, Part 3, Section 3.
1.6.2.1.1 Transponder Failure
1.6.2.1.1.1 Failure before intended departure: If the transponder fails before intended departure and cannot be repaired pilots shall:
  1. Inform ATS as soon as possible preferably before the submission of a flight plan.
  2. Insert in item 10 of the ICAO flight plan under 'Surveillance equipment and capabilities' the letter N for complete unserviceability of the transponder or in the case of partial failure, the letter corresponding to the remaining transponder capability, including unserviceability of any Mode S functionality, as specified in ICAO Doc 4444, Appendix 2.
  3. Comply with any published procedures for requesting an exemption from the requirements to carry a functioning transponder and/or comply with MEL.
  4. If required by the appropriate ATS authority, plan to proceed, as directly as possible to the nearest suitable aerodrome where repair can be carried out.
  5. When granting clearance to such aircraft, ATC will take into account the existing and anticipated traffic situation and may have to modify the time of departure, flight level or route of the intended flight.
1.6.2.1.1.2 Failure after departure: If the transponder fails after departure:
  1. ATS Units will endeavour to provide for continuation of the flight in accordance with the original flight plan.
  2. In certain traffic situations this may not be possible particularly when the failure is detected shortly after take-off. The aircraft may then be required to return to the departure aerodrome or to land at another aerodrome acceptable to the operator and to ATC.
  3. After landing, pilots shall make every effort to have the transponder restored to normal operation. If the transponder cannot be repaired then the provisions in ENR 1.6.2.1.1.1 apply.
1.6.2.1.1.3 Failure for Overflights: If the transponder fails en-route:
  1. When ATC units are informed or it becomes apparent that an aircraft is about to enter Emirates FIR without a functioning transponder entry clearance will be denied.
  2. In the event an emergency is declared, overflight of the FIR will not be permitted but the aircraft will be allowed to land at an airport within the UAE.
  3. After landing, pilots shall make every effort to have the transponder restored to normal operation. If the transponder cannot be repaired then the provisions in ENR 1.6.2.1.1.1 apply.
1.6.2.1.1.4 The temporary failure of Mode C alone would not restrict the normal operation of the flight.
1.6.2.1.2 Transponder Testing
1.6.2.1.2.1 Transponder testing has the potential to generate false SSR returns, thereby incorrectly triggering safety nets such as TCAS and short term conflict alert, with consequential disruption to flight crews and ATC, potentially causing an adverse safety impact. Therefore, individuals or organisations intending to conduct ground-based transponder testing and maintenance, shall take necessary precautions to ensure transponder transmissions cannot be erroneously identified as valid replies by airborne or ground interrogator systems that may detect them. Consequently, the following steps are strongly recommended:
  1. Set the Mode A code to 0000.
  2. Use effective screening or absorption devices on the antennas or physically connect the ramp test set to the antenna system.
  3. Where possible, conduct the testing inside a hangar, as this may provide additional shielding.
  4. Manually set the Mode C pressure-altitude data to either a high value (eg over 60000 FT) or an unrealistically low value (eg. 2000 FT below ground).
  5. Select the transponder(s) to 'OFF' or 'STANDBY' when testing is complete.
1.6.2.1.2.2 Additional guidance on transponder testing can be found in ICAO Annex 10 Vol IV, JAA TGL 13.
1.6.2.2 Radio communication failure and unlawful interference procedures
  1. Radio communication failure procedure whilst under radar control is as detailed in ENR 1.6.1.3.

  2. Aircraft subject to unlawful interference shall follow the procedures specified in Annex 2 - Rules of the Air, Attachment B.

  3. Whenever possible aircraft experiencing unlawful interference shall select SSR Mode A Code 7500.

1.6.2.3 System of SSR code assignment
  1. The UAE uses 4 digit code blocks assigned under the originating region code allocation method. (ORCAM)

  2. Aircraft entering the Emirates FIR shall retain the SSR code previously issued by ATC in an adjacent FIR.

  3. The following SSR codes (Mode A) will be assigned by Emirates ACC:

    1. International departure from UAE airports:

      0501 to 0577, 1701 to 1777, 3401 to 3477 and 6201 to 6277.
    2. Flights remaining entirely within the Emirates FIR:

      0401 to 0477, 0601 to 0677, 6001 to 6077 and 6101 to 6177.
  4. Only discrete codes shall be assigned to flights. i.e. codes ending in 00 are not used.

1.6.2.4 SSR coverage is provided throughout the FIR. Maximum ranges of the secondary radars used for air traffic services are:
UAE Secondary Radars
LocationTypeMax Range (NM)
Al Ain-1MSSR120
Al Ain-2MSSR250
Abu Dhabi-1MSSR120
Al MaktoumMSSR250
Dubai-1MSSR256
TarifMSSR250
SharjahMSSR250
Ras Al KhaimahMSSR250
1.6.3. Airborne Collision Avoidance System (ACAS)
1.6.3.1 General
1.6.3.1.1 ACAS indications shall be used by pilots in the avoidance of potential collisions, enhancement of situational awareness, and the active search for, and visual acquisition of, conflicting traffic. The ability of ACAS to fulfil its role of assisting pilots in the avoidance of potential collisions is dependent on the correct and timely response by pilots to ACAS indications.
1.6.3.1.2 In the event of a Resolution Advisory (RA) ATC expects pilots to respond immediately and inform ATC as soon as possible of any deviation from an ATC clearance and should return to their original flight path as soon as it is safe and practical to do so.
1.6.3.2 Operation of Aircraft when ACAS II is unserviceable
1.6.3.2.1 Due to the safety benefits arising from TCAS operations and the collaborative way in which it arrives at collision avoidance solutions any aircraft with an unserviceable transponder as well as an unserviceable TCAS will not be permitted in the Emirates FIR for which mandatory carriage of a transponder is required.

Note: See GEN 1.5.6

1.6.4. Wide Area Multilateration (WAM) System
1.6.4.1 Approach Surveillance control is provided within Fujairah CTA under Wide Area Multilateration (WAM) System, between 0300 - 1100 UTC only except Friday and Saturday.
1.6.4.2 WAM coverage is 40 NM from OMFJ ARP within the vertical limits of Fujairah CTA in accordance with ATC Surveillance Minimum Altitude chart OMFJ-AD-2-51.
1.6.4.3 Operating procedures
  1. Aircraft are required to operate SSR transponders selecting Mode A and Mode C simultaneously
  2. Aircraft entering Fujairah CTA shall retain the SSR code last assigned by adjacent ATC units
  3. Aircraft shall report maintaining level/altitude and position on first contact with FUJAIRAH APPROACH to facilitate verification of Mode C altitude information
  4. Surveillance separation minima shall be applied as follows:
    1. 5 NM surveillance separation
    2. Not less than 8 NM surveillance spacing between two aircraft when established on final for runway in use
1.6.4.4 In the event of Surveillance System failure or loss of surveillance contact, instructions will be issued to restore standard longitudinal, lateral or vertical separation between aircraft operating with surveillance separation.