For the purpose of this chapter— (1) “ Secretary ” means the Secretary of the Department in which the Coast Guard is operating; (2) “ power-driven vessel ” means any vessel propelled by machinery; and (3) “ towing vessel ” means any commercial vessel engaged in towing another vessel astern, alongside, or by pushing ahead. ( Pub. L. 92–63, § 3 , Aug. 4, 1971 , 85 Stat. 164 .) Statutory Notes and Related Subsidiaries Effective Date Section effective May 1, 1971 , or six months after the promulgation of regulations which would implement its provisions, whichever is later, see section 10 of Pub. L. 92–63 , set out as a note under section 1201 of this title . Transfer of Functions For transfer of authorities, functions, personnel, and assets of the Coast Guard , including the authorities and functions of the Secretary of Transportation relating thereto, to the Department of Homeland Security , and for treatment of related references, see sections 468(b), 551(d), 552(d), and 557 of Title 6, Domestic Security, and the Department of Homeland Security Reorganization Plan of November 25, 2002 , as modified, set out as a note under section 542 of Title 6 . CFR Title Parts 33 26