Requirement to register.
No person may operate a small unmanned aircraft that is eligible for registration under 49 U.S.C. 44101-44103 unless one of the following criteria has been satisfied:
(a) The owner has registered and marked the aircraft in accordance with this part;
(b) The aircraft weighs 0.55 pounds or less on takeoff, including everything that is on board or otherwise attached to the aircraft; or
(c) The aircraft is an aircraft of the Armed Forces of the United States.