Mainsail

The primary sail attached to the mast and boom.

How to sign

Use Dominant flat-B or 1-hand outlines the sail edge. The base or passive hand is Non-dominant upright 1-hand: mast; horizontal flat-B: boom if needed. Set mast and boom. Start at the masthead, aft of the mast. Outline one large triangular sail from masthead to boom and aft to the clew. Hold the triangle aft of the mast; do not place it forward. Use the lexical SAIL sign, then place a large triangular sail aft of the mast in the boat locus. Trace mast-to-boom placement once; keep the sail behind the mast.