On March 22, pilot James Langenhahn was stowing his Heckler & Koch USP .40, issued to him by the Department of Homeland Security under the Federal Flight Deck Officer program, while his co-pilot prepared to land the plane. ..... Ray, Feds can carry weapons when not on duty, even when flying on vacation. Its called statutory authority. Something that FFDOs do not have. They are deputized to carry a weapon in support of their official duties in the cockpit. Nothing else. ...