{"data":{"id":"us/14-cfr-91.173","jurisdiction":"us","citation":"14 CFR 91.173","heading":"ATC clearance and flight plan required.","body":"No person may operate an aircraft in controlled airspace under IFR unless that person has—\n(a) Filed an IFR flight plan; and\n(b) Received an appropriate ATC clearance.","path":["Title 14—Aeronautics and Space","CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","SUBCHAPTER F—AIR TRAFFIC AND GENERAL OPERATING RULES","PART 91—GENERAL OPERATING AND FLIGHT RULES","Subpart B—Flight Rules"],"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":"352f7537bbc0551b14deaac6523d6f90ec6e630b5fadda990f78dfb7078d1bc2","source_id":"us-cfr","stale":true,"prev":"us/14-cfr-91.171","next":"us/14-cfr-91.175"},"notice":"GroundRules: Original legal text. Not legal advice."}