§ 135.119
Prohibition against carriage of weapons.
No person may, while on board an aircraft being operated by a certificate holder, carry on or about that person a deadly or dangerous weapon, either concealed or unconcealed. This section does not apply to—
(a) Officials or employees of a municipality or a State, or of the United States, who are authorized to carry arms; or
(b) Crewmembers and other persons authorized by the certificate holder to carry arms.