§ 21.181 Duration
(a) Unless sooner surrendered, suspended, revoked, or a termination date is otherwise established by the Administrator, airworthiness certificates are effective as follows:
(1) Standard airworthiness certificates, special airworthiness certificates - primary category, and airworthiness certificates issued for restricted or limited category aircraft are effective as long as the maintenance, preventive maintenance, and alterations are performed in accordance with Parts 43 and 91 of this chapter and the aircraft are registered in the United States.
(2) A special flight permit is effective for the period of time specified in the permit.
(3) An experimental certificate for research and development, showing compliance with regulations, crew training, or market surveys is effective for one year after the date of issue or renewal unless a shorter period is prescribed by the Administrator. The duration of amateur built, exhibition, and air racing experimental certificates will be unlimited unless the Administrator finds for good cause that a specific period should be established.
(b) The owner, operator, or bailee of the aircraft shall, upon request, make it available for inspection by the Administrator.
(c) Upon suspension, revocation, or termination by order of the Administrator of an airworthiness certificate, the owner, operator, or bailee of an aircraft shall, upon request, surrender the certificate to the Administrator.
[Amdt. 21-21, 33 FR 6858, May 7, 1968, as amended by Amdt. 21-49, 44 FR 46781, Aug. 9, 1979; Amdt. 21-70, 57 FR 41368, Sept. 9, 1992]
