Materials.

CFR · 2024-01-01 · US · Title 14

The suitability and durability of materials used in the engine must— (a) Be established on the basis of experience or tests; and (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.

official document · source cfr-2024 · id 14:§ 33.15