{"data":{"id":"us/14-cfr-33.15","jurisdiction":"us","citation":"14 CFR 33.15","heading":"Materials.","body":"The suitability and durability of materials used in the engine must—\n(a) Be established on the basis of experience or tests; and\n(b) Conform to approved specifications (such as industry or military specifications) that ensure their having the strength and other properties assumed in the design data.","path":["Title 14—Aeronautics and Space","CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","SUBCHAPTER C—AIRCRAFT","PART 33—AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES","Subpart B—Design and Construction; General"],"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":"18b39e31713df313488877032492192185967f811096d5ceeddb7db1fd24d4c6","source_id":"us-cfr","stale":true,"prev":"us/14-cfr-33.13","next":"us/14-cfr-33.17"},"notice":"GroundRules: Original legal text. Not legal advice."}