14 C.F.R. § 21.609 Approval for deviation.
Title 14 - Aeronautics and Space
(a) Each manufacturer who requests approval to deviate from any performance standard of a TSO shall show that the standards from which a deviation is requested are compensated for by factors or design features providing an equivalent level of safety. (b) The request for approval to deviate, together with all pertinent data, must be submitted to the Manager of the Aircraft Certification Office for the geographic area in which the manufacturer is located. If the article is manufactured in another country, the request for approval to deviate, together with all pertinent data, must be submitted through the civil aviation authority in that country to the FAA. [Doc. No. 19589, 45 FR 38346, June 9, 1980, as amended by Amdt. 21–67, 54 FR 39291, Sept. 25, 1989]
Title 14: Aeronautics and Space
PART 21—CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS
Subpart O—Technical Standard Order Authorizations
§ 21.609 Approval for deviation.