AC 120-55C Air Carrier TCAS - Code7700

2/23/11 AC 120-55Cavoidance system algorithms as defined by RTCA/DO-185, to the Aircraft Engineering Division,AIR-100, Washington, D.C.14. FAA RESPONSE TO TCAS EVENTS. Regarding regulatory compliance issues, the FAAwill not initiate enforcement action solely on the basis of a TCAS event. Letters of investigationwill not be sent to pilots involved in a TCAS-related deviation provided:a. Aircrafts Equipped with TCAS. The aircraft was equipped with TCAS, the system wasoperable, and the equipment was turned on at the time of the event;b. Compliance with ATC Clearances. The pilots have properly operated their aircraft incompliance with ATC clearances prior to the TCAS-related deviation;c. Compliance with TCAS Training. The pilots have successfully completed their aircarrier’s FAA-approved TCAS training program; andd. Compliance with § 91.123. The pilots have otherwise complied with the requirements of§ 91.123.15. FOREIGN AIR CARRIERS.a. General. Section 129.18 requires TCAS II installation and use by certain foreign aircarriers when operating in U.S. airspace. Foreign air carriers are not required to install and useTCAS for any aircraft or operations taking place outside of the U.S. 12 NM territorial limit(§ 71.9), even though separation services may be provided by a U.S. ATC facility (for example,in oceanic airspace). Various states may abide by ICAO guidance found in ACAS Standards andRecommended Practices (SARPS).(1) TCAS Approval for Foreign Air Carriers. The FAA does not approve TCASinstallation, training programs, MELs, or maintenance programs for foreign operators operatingnon-U.S.-registered aircraft. Such authorizations are addressed as specified by the State ofOperator or by ICAO. However, since compatibility of TCAS and Mode S transponders withother aircraft and NAS facilities within U.S. airspace is essential, the FAA issues part 129operations guidelines for TCAS to all foreign air carrier operations within U.S. airspace.Compliance with these TCAS provisions ensures both TCAS system and proceduralcompatibility. The issuance of OpSpecs, or an amendment to existing OpSpecs for TCAS, musttake place before a foreign air carrier operating a TCAS-equipped aircraft in U.S. airspace, inaccordance with § 129.18. Standard provisions for foreign air carriers for TCAS are shown inAppendix 4.(2) Guidance. Guidance for foreign air carriers operating under part 129 applies tonon-U.S.-registered aircraft as well as U.S.-registered aircraft flying in U.S. airspace. The plan ofState of Registry for U.S.-registered aircraft operated by foreign operators is, for practicalpurposes, that of the U.S. or the same as that for any U.S. operator in order to meet therequirements of § 129.14.Par 13 Page 15