49 U.S.C. § 44101

Operation of aircraft

(a) Registration Requirement.—

Except as provided in subsection (b) of this section, a person may operate an aircraft only when the aircraft is registered under section 44103 of this title .

(b) Exceptions.—

A person may operate an aircraft in the United States that is not registered—

(1)

when authorized under section 40103(d) or 41703 of this title;

(2)

when it is an aircraft of the national defense forces of the United States and is identified in a way satisfactory to the Administrator of the Federal Aviation Administration; and

(3)

for a reasonable period of time after a transfer of ownership, under regulations prescribed by the Administrator.

( Pub. L. 103–272, § 1(e) , July 5, 1994 , 108 Stat. 1161 .)