1.1 In pursuant to ICAO Annex 6, Part 1, Chapter 6, all turbine-engined aeroplanes of a maximum certified take-off mass in excess of 5700 kg or authorised to carry more than 19 passengers flying within the Singapore FIR and the airspace within the Jakarta FIR where ATS is provided by Singapore (see ENR 2.1) shall be equipped with an airborne collision avoidance system (ACAS II) and to operate the ACAS system in accordance with the relevant provisions of Annex 10, Volume IV, Chapter 4.