Contact

The Civil Aviation Authority of Thailand
Aeronautical Information Service Department
333/105 Lak Si Plaza, Khamphaeng Phet 6 Rd.
Talat Bang Khen, Lak Si, Bangkok 10210, Thailand

Tel: +662 568 8831

Fax: +662 576 1903

AFS: VTBAYOYX

E-mail: aisthai@caat.or.th

E-mail: ais@caat.or.th

AIC for Thailand

AIC

02/24

Effective from 25 JAN 2024

to UFN

Published on 14 DEC 2023

Implementation of Automatic Dependent Surveillance - Broadcast (ADS-B)
for Air Traffic Services in Bangkok Flight Information Region (FIR) in 2024

1 INTRODUCTION

The purpose of this Aeronautical Information Circular (AIC) is to inform aircraft operators that the Aeronautical Radio of Thailand Limited (AEROTHAI), as Thailand’s air traffic services (ATS) provider, will implement Automatic Dependent Surveillance - Broadcast (ADS-B) to complement the existing Secondary Surveillance Radar (SSR) coverage and enhance ATS surveillance service within the Bangkok Flight Information Region (Bangkok FIR). The enhanced surveillance coverage will improve safety and increase air traffic control capacity, enabling safer and more efficient flow of air traffic. The implementation of ADS-B is planned to commence 18 April 2024.

2 BACKGROUND

ADS-B is a surveillance technology that enables aircraft to periodically broadcast its position obtained from Global Navigation Satellite Systems (GNSS), enabling it to be tracked for air traffic service purposes. Aircraft positioning information can be received by air traffic control ground stations and, in some cases, by other aircraft, providing enhanced situational awareness for both the air traffic control officers and the pilots.

AEROTHAI has been working on the implementation of ADS-B technology in air traffic services, and is in the process of obtaining approval from the Civil Aviation Authority of Thailand (CAAT). The implementation project aims to increase capacity, improve efficiency, and enhance safety
of air traffic services within the Bangkok FIR. This initiative is in line with the International Civil Aviation Organization (ICAO) Global Air Navigation Plan (GANP) and the Asia/Pacific Air Navigation Plan.

3 IMPLEMENTATION

The implementation of ADS-B will complement the existing SSR system and will provide air traffic services with more accurate and reliable aircraft positioning data. It will also support advanced air traffic management procedures, such as reduced aircraft separation and more efficient routing for aircraft equipped with ADS-B Out avionics.

Beginning 18 April 2024, aircraft operating within the Bangkok FIR that have obtained ADS-B operations specifications approvals from their State Authorities will be given ATS surveillance service within the ADS-B coverage. Aircraft with no ADS-B operations specifications approvals will be given ATS surveillance service only within the SSR coverage.

Note that the period between 18 April - 13 June 2024 is planned as the operational trial phase. Provided there is no significant safety concerns, the full implementation of ADS-B based ATS surveillance service will commence from 11 July 2024. Should the service need to be suspended
due to operational, technical, or safety considerations, a new AIC will be issued to notify of the new implementation plan.

4 AIRCRAFT OPERATORS’ RESPONSIBILITIES

4.1 Aircraft Operators intending to operate aircraft equipped with ADS-B Out avionics, with appropriate operations specifications approvals obtained, within Bangkok FIR after 18 April 2024 must file either “B1” or “B2” in Item 10b of their flight plans according to their equipage.

4.2 Aircraft Operators should also ensure that their flight crews are familiar with the operation of the ADS-B equipment on board the aircraft and are aware of any limitations or differences in operation compared to SSR.

4.3 If the ADS-B transmitter onboard the aircraft becomes inoperable or does not meet required operational approval standards, the ADS-B transmitter should either be:

1) Deactivated; or

2) Set to transmit only a value of zero for the Navigation Uncertainty Category (NUCp) or Navigation Integrity Category (NIC)
or Navigation Accuracy Category (NAC) or Source Integrity Limit (SIL)

Note:

- The requirement is met if the ADS-B transmitting equipment has a cockpit control that enables the pilot to turn the ADS-B transmissions on and off without disabling the ATC transponder.

- Deactivation of the ADS-B transmissions must not affect the continued operation of the Mode S transponder responses to

interrogations.

- It is considered equivalent to deactivation if NUCp or NIC or NAC or SIL is set to continually transmit only a value of zero.

5 CONTACT

For additional information or clarification regarding the implementation of ADS-B in the Bangkok FIR, please contact:

5.1 Aeronautical Radio of Thailand Limited (AEROTHAI)

MR. PAKORN SINGHARUANG
Tel: +662 285 9849, +668 9812 6719
Fax: +662 285 9145
Email: pakorn.si@aerothai.co.th

5.2 The Civil Aviation Authority of Thailand (CAAT)

CAAT - Air Navigation Services Standards Department (ANS)
MR. SARAWOOT RUNGRUENGWAJIAKE
Tel: +662 568 8825 Ext. 0808
Email: sarawoot.r@caat.or.th

CAAT - Flight Operation Standards Department (OPS)
MR. APIWAT TORPRADIT
Tel: +662 568 8843 Ext. 0631
Email: apiwat.t@caat.or.th