14 C.F.R. § 27.305 Strength and deformation.
Title 14 - Aeronautics and Space
(a) The structure must be able to support limit loads without detrimental or permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The structure must be able to support ultimate loads without failure. This must be shown by— (1) Applying ultimate loads to the structure in a static test for at least three seconds; or (2) Dynamic tests simulating actual load application.
Title 14: Aeronautics and Space
PART 27—AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT
Subpart C—Strength Requirements
General
§ 27.305 Strength and deformation.
