14 CFR § 47.16 - Temporary registration numbers.
(a) Temporary registration numbers are issued by the FAA to manufacturers, distributors, and dealers who are holders of Dealer's Aircraft Registration Certificates, AC Form 8050-6, for temporary display on aircraft during flight allowed under Subpart C of this part.
(b) The holder of a Dealer's Aircraft Registration Certificate may apply to the Registry for as many temporary registration numbers as are necessary for his business. The application must be in writing and include -
(1) Sufficient information to justify the need for the temporary registration numbers requested; and
(2) The number of each Dealer's Aircraft Registration Certificate held by the applicant.
(c) The use of temporary registration numbers is subject to the following conditions:
(1) The numbers may be used and reused -
(i) Only in connection with the holder's Dealer's Aircraft Registration Certificate;
(2) A temporary registration number may not be used on more than one aircraft in flight at the same time.
(d) The assignment of any temporary registration number to any person lapses upon the expiration of all of his Dealer's Aircraft Registration Certificates. When a temporary registration number is used on a flight outside the United States for delivery purposes, the holder shall record the assignment of that number to the aircraft and shall keep that record for at least 1 year after the removal of the number from that aircraft. Whenever the owner of an aircraft bearing a temporary registration number applies for an airworthiness certificate under Part 21 of this chapter he shall furnish that number in the application. The temporary registration number must be removed from the aircraft not later than the date on which either title or possession passes to another person.
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