View all text of Subpart B [§ 38.11 - § 38.23]
§ 38.21 - Approval before compliance testing.
All procedures, weights, configurations, and other information or data that are used to establish a fuel efficiency level required by this part or in any appendix to this part (including any equivalent procedures) must be approved by the FAA prior to use in certification tests intended to demonstrate compliance with this part.