Mast

A principal upright or near-upright spar or structure that supports sails, rigging or equipment aboard a vessel.

A sailing mast carries sail and rig loads through standing and running rigging and may be deck-stepped or keel-stepped. Power vessels also use masts for lights, antennas, radar, signals and sensors, and construction may be timber, aluminium, steel or composite.

Masts carry compression, bending and torsion and depend on sound partners, step, stays, terminals and attachments. Work aloft, electrical conductors, corrosion, fatigue and objects falling from height require planned inspection and safe access arrangements.