ATS jurisdiction in FIRs. A Contracting State discharges the responsibility to provide ATS118 through conferring the competence to its designated ATS authority for territorial airspace – sovereign jurisdiction;119 meanwhile, an ATS authority may have the compet- ence to regulate airspaces beyond national territories: the appropriate ATS authority therein manages flight information regions (FIRs) under its jurisdiction, which can extend across sovereign territories, and/or extend over high seas, and/or to areas of undetermined sovereignty – ATS jurisdiction.120 The concept FIR is not mentioned in the Chicago Convention but is defined in Annex 11 of the Chicago Convention as “an airspace of defined dimensions within which flight information service (FIS) and alerting service are pro- vided.”121 The term FIR is defines dimensions of airspaces where the provision ATS falls within the jurisdiction of one authority.122 FIRs can encompass sover- eign airspace, airspace over the high seas, and airspace of undetermined sovereignty, subject to conditions in Annex 11 regarding their establish- ment.123 FIRs are primarily set up pursuant to technical considerations.124 For example, the Singapore FIR was developed to achieve maximum efficiency in the provision of ATS to aircrafts with an emphasis on safety.125 Singaporean ATS authorities may continue having the competence to manage 118 The connotation of responsibility in relation with competence, see further Section 4 of this chapter. 119 See Section 3.2 of this chapter. 120 See xxxxx://xxx.xxxx.xxx/icaofir/. The ICAO GIS Services is an electronic database based on the geographical (FIRs) from around the world. 121 FIR is “An airspace of defined dimensions within which flight information service and alerting service are provided.” I Annex 11, p.1-7. 122 FIRs are identified by the name of the unit having jurisdiction in such airspace, such as Singapore FIR or Hanoi FIR. See Annex 11, Recommendation 2.12.3. 123 Annex 11, Section 2.5, Designation of the portions of the airspace and controlled aerodromes where air traffic services will be provided:
