Glossary

(1) In U.S. practice, an extension to the boom mounted at the boom tip, in line with the boom longitudinal axis or offset to it. (2) On tower cranes, the structural member extending forward from the mast to support the lifting trolley, sheaves, hook block, and load. (3) In Europe, the term used for a crane boom. Correspondingly, the extension to the main boom is known as a fly jib.