Multi hul Cruising fundamentals The official text of the American Sailing AssociationÆs Cruising Multihull Standard (CM) Certification, this guide addresses everything beginning-to-intermediate multihull cruisers need to know to sail and Charter these swift, versatile vessels. Covering trailerable and cruising catamarans and trimarans, it discusses such topics as systems, draft, capsize prevention, maintenance, handling boats under sail or power, docking and mooring, heavy weather and reefing.