Section 46505(a) of Title 49 contains the definition of "loaded firearm."
Section 46505(b) of Title 49 (formerly 49 U.S.C. App. § 1472(l)(1)) contains misdemeanor penalties for: (1) boarding, or attempting to board an aircraft in, or intended for operation in, air transportation or intrastate air transportation, by a person possessing, on or about his/her person or property, a concealed deadly or dangerous weapon which is, or would be, accessible to him/her in flight; (2) placing or attempting to place aboard any such aircraft a loaded firearm in the baggage or other property not accessible to passengers in flight; and (3) placing or attempting to place aboard any such aircraft any bomb or similar explosive or incendiary device. Section 46505(c) makes it a felony for anyone who willfully and without regard for the safety of human life commits an act prohibited by § 46505(b). Section 46505(d) provides that the section does not apply to any officer or employee of the Federal government who is authorized or required in his/her official capacity to carry arms.
[cited in JM 9-63.100; JM 9-63.161]