{"data":{"id":"us/14-cfr-121.356","jurisdiction":"us","citation":"14 CFR 121.356","heading":"Collision avoidance system.","body":"Effective January 1, 2005, any airplane you operate under this part must be equipped and operated according to the following table:\nCollision Avoidance Systems\nIf you operate any— Then you must operate that airplane with—\n(a) Turbine-powered airplane of more than 33,000 pounds maximum certificated takeoff weight (1) An appropriate class of Mode S transponder that meets Technical Standard Order (TSO) C-112, or a later version, and one of the following approved units: (i) TCAS II that meets TSO C-119b (version 7.0), or takeoff weight a later version.\n(ii) TCAS II that meets TSO C-119a (version 6.04A Enhanced) that was installed in that airplane before May 1, 2003. If that TCAS II version 6.04A Enhanced no longer can be repaired to TSO C-119a standards, it must be replaced with a TCAS II that meets TSO C-119b (version 7.0), or a later version. (iii) A collision avoidance system equivalent to TSO C-119b (version 7.0), or a later version, capable of coordinating with units that meet TSO C-119a (version 6.04A Enhanced), or a later version.\n(b) Passenger or combination cargo/passenger (combi) airplane that has a passenger seat configuration of 10-30 seats (1) TCAS I that meets TSO C-118, or a later version, or (2) A collision avoidance system equivalent to has a TSO C-118, or a later version, or (3) A collision avoidance system and Mode S transponder that meet paragraph (a)(1) of this section.\n(c) Piston-powered airplane of more than 33,000 pounds maximum certificated takeoff weight (1) TCAS I that meets TSO C-118, or a later version, or (2) A collision avoidance system equivalent to maximum TSO C-118, or a later version, or (3) A collision avoidance system and Mode S transponder that meet paragraph (a)(1) of this section.","path":["Title 14—Aeronautics and Space","CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","SUBCHAPTER G—AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS","PART 121—OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS","Subpart K—Instrument and Equipment Requirements"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-14.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:20Z","sha256":"50161e7c4518e532dea8bbbae79730a6b4cefffeba282831c59186251175fcd7","source_id":"us-cfr","stale":true,"prev":"us/14-cfr-121.355","next":"us/14-cfr-121.357"},"notice":"GroundRules: Original legal text. Not legal advice."}