2.1.1  The States of the ICAO Asia/Pacific Region, which have westbound flights operating through the Kabul FIR between 2000UTC to 2359UTC, are re-activating the integrated Air Traffic Flow Management (ATFM) service using the Bay of Bengal Cooperative ATFM System (BOBCAT).

2.1.2  The Kabul FIR Contingency Coordination Team teleconference (23 April 2025) along with the BOBCAT Resumption Side Meeting during-slot the Fifteenth Meeting of the Asia/Pacific Air Traffic Flow Management Steering Group (ATFM/SG/15, Bangkok, Thailand, from 28 April to 2 May 2025) agreed to the resumption of the BOBCAT ATFM procedures to support the ongoing Afghanistan contingency arrangement, to alleviate operational and environmental impact while en-route ATC service remained absent

2.2.1  As one of the ATFM services provided, Bangkok ATFMU provides ATFM service for westbound flights intending to transit Kabul FIR between 2000 UTC and 2359 UTC daily. The service provided includes calculation, promulgation, and management of mandatory Calculated Take-Off Time (CTOT) and flight level, ATS route, and Calculated Time-Over (CTO) at entry waypoint for entry into Kabul FIR for each affected flight.

2.2.2  Bangkok ATFMU utilizes the automated, web-based BOBCAT in providing ATFM service in the Kabul FIR. These responsibilities will be managed in coordination with airspace users and ANSPs concerned

2.2.3  The objectives of this service are to:

1. Reduce ground and en-route delays;

2. Maximize capacity and optimize air traffic flow through Kabul FIR;

3. Provide an informed choice of routing and flight level selection;

4. Alleviate unplanned in-flight re-routing and technical stops; and

5. Assist regional ANSPs in planning for and managing workload in handling increased air traffic flow through Kabul FIR.

2.3.1  All westbound flights intending to transit the Kabul FIR between 2000UTC and 2359UTC daily on ATS routes and flight level in Table 1 shall comply with the BOBCAT ATFM procedures contained herein. These flights are required to obtain a slot allocation from the BOBCAT system. This includes a mandatory requirement for all flights to obtain a specific ATFM slot allocation – CTOT, CTO at Kabul FIR entry waypoint, allocated flight level, and allocated ATS route – from the Bangkok ATFMU for entry into Kabul FIR during the period above mentioned.

2.3.2  Flights that plan to enter Kabul FIR without an ATFM slot allocation – CTOT, CTO at Kabul FIR entry waypoint, allocated flight level, and allocated ATS route – will be accommodated only after flights with slots have been processed. Such flights should expect delayed pushback and start clearances, non-preferred routes and/or flight levels, en-route holding and/or diversion around Kabul FIR.

2.4.1  The following flights are exempted from BOBCAT ATFM procedures:

1. flights experiencing an emergency, including aircraft subject to unlawful interference;

2. flights on search and rescue (SAR) or rescue and firefighting (RFF) missions;

3. urgent medical evacuation flights specifically declared by medical authorities where flight delays would put the life of patients at risk;

4. flights with “Head of State” status; or,

5. other flights specifically identified by State authorities.

2.4.2  Flight exempted from ATFM shall indicated the exemption in their flight plan (Field 18 - STS/ATFMX).

2.4.3  Airspace users uncertain whether their flights should be exempted should contact Bangkok ATFMU for clarification.

2.5.1  Affected flights shall obtain the mandatory Kabul FIR slot allocation – CTOT, CTO at Kabul FIR entry waypoint, and allocated flight level and ATS route from the BOBCAT system. The Kabul FIR slot allocation will enable ANSPs to tactically control westbound flights transiting the Kabul FIR at specified times by assigning minimum spacing requirements at specified FIR boundary waypoints of the Kabul FIR.

2.5.2  The application, calculation, and distribution of CTOT and associated Kabul FIR entry waypoint slot allocations will be managed via internet access to the BOBCAT system in accordance with the BOBCAT ATFM operating procedures in section 2.6.

2.6.1  All affected flights are required to submit slot requests to the BOBCAT system by logging into https://www.bobcat.aero between 0000 and 1159UTC on the day of flight and completing the electronic templates provided.

2.6.2  Affected operators who do not have dedicated BOBCAT username/password access should complete the attached application form in Appendix B in "Bay of Bengal and South Asia Air Traffic Flow Management Handbook" and email the form to the Bangkok ATFMU as soon as possible.

2.6.3  Slot Allocation Process

The slot allocation is divided into 3 phases, namely; the slot request submission, initial slot allocation, and slot distribution to aircraft operators and ANSPs.

1. Slot Request Submission

   1. Slot requests including preferred ATS route, flight level and Maximum Acceptable Delay (MAD) should be lodged between 0000UTC and 1159UTC on the day of flight. Slot requests may subsequently be amended prior to the cut-off time of 1200UTC. Aircraft operators are encouraged to submit additional slot request options in case their first choice is not available. This may include variations to ATS route, flight level and MADs.

   2. Slot requests shall be for flight parameters that are able to be met by the flight. For example, flights requesting a slot at FL360 must be able to enter Kabul FIR at FL360. Flight subsequently unable to meet slot parameters (flight level, ATS route, or CTO at Kabul FIR entry waypoint) should expect non-preferred routes and/or flight levels, en-route holding and/or diversion around Kabul FIR.

   3. Flights that were not allocated a slot in the initial slot allocation, are not satisfied with the allocated slot or did not submit a slot request should select slots from the listing of remaining unallocated slots available immediately after slot distribution has been completed.

2. Slot Allocation and Distribution

   1. Slot allocation will commence at the cut-off time of 1200UTC. BOBCAT will process and generate the slot allocation based on the information submitted in the slot requests. Notification of slot allocation will be made not later than 1230UTC via the BOBCAT ATFM website and via AFTN using Slot Allocation Message (SAM) in accordance with the Asia/Pacific AFTN/AMHS-Based Interface Control Document.

   2. After the slot allocation has been published at https://www.bobcat.aero, airspace users can:

      1. Use the slot allocation result for flight planning purposes,

      2. Cancel the allocated slot and/or,

      3. Change slot allocation to another available slot in the published list of unallocated slots.

2.6.4  Submission of ATS Flight Plan

1. Once aircraft operators are in receipt of the slot allocation, they shall submit the ATS flight plan using the time, ATS route and flight level parameters of the BOBCAT allocated slot.

2. When submitting the ATS flight plan, the aircraft operator shall ensure that the callsign corresponds exactly to the one submitted in the BOBCAT system.

2.7.1  In accordance with ICAO PANS-ATM provisions, it is the responsibility of the Pilot-in-Command (PIC) and the airspace user to ensure that the aircraft is ready to taxi in time to meet any required departure time. PIC shall be kept informed by their operators of the CTOT, CTO at Kabul FIR entry waypoint, and flight parameters (route, flight level) allocated by BOBCAT.

2.7.2  The PIC, in collaboration with ATC, shall arrange take-off as close as possible to CTOT in order to meet the allocated CTO at Kabul FIR entry fix.

2.7.3  For flights with CTOTs from BOBCAT departing from Noi Bai and Tan Son Nhat international airports, where the CTOT is integrated into the A-CDM process, PIC are advised to comply with the local A-CDM procedure.

Air Navigation Service Providers (ANSPs)

2.7.4  In accordance with ICAO PANS-ATM provisions, flights with an ATFM slot allocation should be given priority for take-off to facilitate compliance with CTOT.

2.7.5  CTOT shall be included as part of the initial ATC clearance. In collaboration with the PIC, Aerodrome Control shall ensure that every opportunity and assistance is granted to a flight to meet CTOT and allocated CTO at Kabul FIR entry waypoint.

2.8.1  Bangkok ATFMU (VTBBZDZX) shall be included in the list of AFTN addressees for ATS messages (e.g. FPL, DEP, DLA, CHG, CNL) relating to flights subject to ATFM procedures.

2.8.2  Prior to departure and before obtaining an ATC Clearance, in circumstances where it becomes obvious that the allocated Kabul FIR slot parameters will not be met, a new slot allocation should be obtained as soon as possible. To avoid frequency congestion, this should be obtained primarily via aircraft operators / flight dispatchers; in case of inability, the current ATC unit may be asked for assistance. Early advice that the allocated slot parameters will be missed also enables the slots so vacated to be efficiently reassigned to other flights.

2.8.3  The PIC shall include the CTOT in the initial ATC clearance request.

2.8.4  A missed slot results in considerable increase in coordination workload for ATC and PIC and should be avoided. To minimize coordination workload in obtaining a revised slot allocation, if the flight is still at the gate and an ATC Clearance has been obtained, PIC shall advice Ground Control/ATC unit of the missed slot and obtains new CTOT as specified in 2.8.2. If it becomes essential, the ATC Clearance may be cancelled.

2.8.5  After the aircraft has left the gate, in the event that the aircraft is unable to meet the allocated Kabul FIR slot parameters, when requested by the PIC, Aerodrome Control shall assist the PIC to revise slot allocation.

2.8.6  PIC shall adjust cruise flight to comply with slot parameters at the Kabul FIR entry waypoint, requesting appropriate ATC clearances including speed variations in accordance with requirements.

2.10.1  Supporting documentation, including detailed information in respect of the BOBCAT ATFM operations described above and other pertinent information has been included in the Bay of Bengal and South Asia ATFM Handbook (the “ATFM Users Handbook”), available at https://www.bobcat.aero.

2.10.2  ANSPs and aircraft operators shall ensure that they are conversant with and able to apply the relevant procedures described in the ATFM Users Handbook.

2.11.1  In the event that an aircraft operator or ATS unit is unable to access the BOBCAT website, Bangkok ATFMU shall be contacted via the alternative means (telephone, AFTN) described in 2.14.

2.11.2  Contingency arrangements are included in the ATFM Users Handbook.

2.11.3  In the event of BOBCAT system failure, Bangkok ATFMU shall notify all parties concerned and advise that BOBCAT ATFM slot allocation procedures are suspended. In this event, all parties concerned will revert to the existing ATM procedures as applicable outside the daily period of ATFM metering.

2.12.1  An ATFM system fault is defined as a significant occurrence affecting an ATS unit, an aircraft operator or ATFMU resulting from the application of ATFM procedures.