ENR 1.6  ATS SURVEILLANCE SERVICES AND PROCEDURES

1  Primary Radar

1.1 Hong Kong primary radar equipment is located at:

2  Secondary Surveillance Radar (SSR)

2.1 Hong Kong secondary surveillance radar equipment is located at:

3  Supplementary Services

3.1 Radar Control Units are operated as an integral part of the Hong Kong ATS unit and provide radar service to aircraft to the maximum extent practicable to meet operational requirements. Many factors, such as radar coverage, controller workload and equipment capabilities, may affect these services, and the radar controller shall determine the practicability of providing, or continuing to provide, radar services in any specific case.
3.2 Pilots shall be advised on commencement and termination of radar services except radar service will be automatically terminated at the time the aircraft leaves the last assigned heading to intercept the ILS localiser.
3.3 Radar identification is achieved according to provisions specified by ICAO.

4  Application of Radar Control Service

4.1 Radar control service is provided in all controlled airspace. This service may include:
  1. Radar separation of arriving, departing and en-route traffic;
  2. Radar monitoring of arriving, departing and en-route traffic to provide information on any significant deviation from the normal flight path;
  3. Radar vectoring when required;
  4. Assistance to aircraft in emergency;
  5. Assistance to aircraft crossing controlled airspace;
  6. Warnings and position information on other aircraft considered to constitute a hazard;
  7. Information to assist in the navigation of aircraft; and
  8. Information on observed weather.
4.2 Levels assigned by radar controllers to pilots will provide a minimum terrain clearance according to the phase of flight.

5  Radar Separation Minima

5.1 Radar separation minima applied between identified aircraft are in accordance with ICAO Doc 4444 PANS-ATM and range from 3 to 10 nautical miles depending on the position of the aircraft in regard to:
  1. the type of airspace they are in,
  2. their distance from the airport or from the radar head, and
  3. the number and types of radar stations that are tracking them.

6  Wake Turbulence Separation and Enhanced Wake Turbulence Separation (eWTS)

6.1 Wake Turbulence Separation
6.1.1 Except as stated in para. 6.2, the following distance-based wake turbulence separation minima utilising aircraft wake turbulence categories shall be applied to aircraft being provided with an ATS surveillance service in the approach and departure phases of flight.
Distance-based Wake Turbulence Separation Minima
Follower
SUPER HEAVY MEDIUM LIGHT
Leader SUPER - 5 NM 7 NM 8 NM
HEAVY - 4 NM 5 NM 6 NM
MEDIUM - - - 5 NM
-  Indicates Wake Turbulence Separation is not applicable
6.2 Enhanced Wake Turbulence Separation (eWTS)
6.2.1 Enhanced wake turbulence separation minima is based on aircraft wake turbulence groups according to the maximum certificated take-off mass, wing span and speed, which govern the wake generation and resistance characteristics of the aircraft.
6.2.2 The wake turbulence groups are:
  • GROUP A - aircraft types of 136 000 kg or more, and a wing span less than or equal to 80 m but greater than 74.68 m;
  • GROUP B - aircraft types of 136 000 kg or more, and a wing span less than or equal to 74.68 m but greater than 53.34 m;
  • GROUP C - aircraft types of 136 000 kg or more, and a wing span less than or equal to 53.34 m but greater than 38.1 m;
  • GROUP D - aircraft types less than 136 000 kg but more than 18 600 kg, and a wing span greater than 32 m;
  • GROUP E - aircraft types less than 136 000 kg but more than 18 600 kg, and a wing span less than or equal to 32 m but greater than 27.43 m;
  • GROUP F - aircraft types less than 136 000 kg but more than 18 600 kg, and a wing span less than or equal to 27.43 m;
  • GROUP G - aircraft types of 18 600 kg or less (without wing span criterion).
6.2.3 The following enhanced wake turbulence separation (eWTS) minima shall be applied to arrival aircraft being provided with an ATS surveillance service on approach to Hong Kong International Airport whilst on base leg and final approach.
Distance-based eWTS Minima
Follower
Group A Group B Group C Group D Group E Group F Group G
Leader Group A - 4 NM 5 NM 5 NM 6 NM 6 NM 8 NM
Group B - 3 NM 4 NM 4 NM 5 NM 5 NM 7 NM
Group C - - - 3 NM 3.5 NM 3.5 NM 6 NM
Group D - - - - - - 4 NM
Group E - - - - - - 4 NM
-  Indicates Wake Turbulence Separation is not applicable
6.2.4 In the event of consecutive missed approaches, eWTS will be applied to aircraft during the initial part of the standard missed approach procedure until another form of separation is established by ATC.

6.3  Wake Turbulence Separation Minima shall not be infringed. In the event of unexpected speed variations between consecutive arrivals on final approach and ATC considers there may be a catch-up situation in which an erosion of the prescribed separation would result, one of the affected aircraft shall be instructed to break off the approach or initiate a missed approach before the prescribed minima is infringed.
6.4 Aircrew shall comply with published speed restrictions or specific speed control instructions assigned by ATC at all times. If for any reason a speed instruction cannot be followed, pilots shall notify ATC accordingly.

7  System of SSR Code Assignment

7.1 Aircraft operating in the Hong Kong FIR can expect to be assigned SSR discrete codes within the following code blocks allocated to HK FIR:
Flight Status SSR Codes
  1. Departing traffic
  2. Traffic diverting from Hong Kong
 3301 - 3377
3501 - 3577
5101 - 5177
5301 - 5377
5701 - 5777
  1. Arriving traffic if not already assigned a SSR code by previous ATC units;
  2. Local/domestic traffic
 5201 - 5277
Overflying traffic if not already assigned a SSR code by previous ATC units 3301 - 3377
3501 - 3577
5101 - 5177
5301 - 5377
5701 - 5777 

8  Transponder Operating Procedures

8.1 Pilots of aircraft outbound from Hong Kong shall operate transponders in accordance with ATC instructions. In addition pilots shall also transpond on Mode C.
8.2 Pilots of aircraft inbound to Hong Kong shall, unless otherwise instructed by the appropriate ATS unit, operate transponders within the Hong Kong FIR to transpond on the SSR code last assigned to them by an ATS unit, or if no code has been previously assigned, to transpond on Code 2000, and to transpond on Mode C.
8.3 Pilots of aircraft inbound to Hong Kong are requested to comply with para. 8.2 above when they are within 300 NM of Hong Kong, although they may be outside Hong Kong FIR.
8.4 Except as stated in paras. 8.5, 8.6 and 8.7 below, pilots who have received specific instructions from ATC concerning the setting of the transponder should maintain that setting unless otherwise instructed.
8.5 To indicate that a state of emergency exists, the pilot of an aircraft shall set the transponder to Code 7700.
8.6 To indicate that a pilot has lost two-way communication, the pilot of an aircraft shall set the transponder to Code 7600.
8.7 Should an aircraft in flight be subjected to unlawful interference, the pilot shall endeavour to set the transponder to Code 7500 to give indication of the situation unless circumstances warrant the use of Code 7700. When a pilot has selected Code 7500 and is subsequently requested to confirm the code by ATC, the pilot shall, according to circumstances, either confirm this or not reply at all. (The absence of a reply from the pilot will be taken by ATC as an indication that the use of Code 7500 is not due to an inadvertent false code selection).

9  Radar Failure

9.1 In the event of a radar failure, the radar controller, in conjunction with the non-radar controller, shall provide non-radar separation as soon as possible and instruct aircraft to communicate with the appropriate non-radar controller for further instructions. Reduced vertical separation (e.g. 500 ft) may be employed temporarily if standard separation cannot be provided immediately. 

10  Radio Communication Failure

10.1 In the event of an aircraft experiencing a two-way communication failure whilst receiving a radar service, the pilot shall comply with the standard radio communication failure procedures (see ENR 1.5).