A mast-aft rig is a sailboat sail-plan that uses a single mast set in the aft half of the hull.The mast supports fore-sails that may consist of a single jib, multiple staysails, or a crab claw sail.[2] In the typical Bermuda rig, the sails located in front of the mast generally deliver a higher percentage of the driving force.The cutter, with its use of multiple foresails, achieves the same goal of placing a higher percentage of the sail area in staysails.[2] By moving the mast toward the back of the sailboat, designers can increase the size and driving power of the more efficient foresails.[2] By reducing the mainsail in size or eliminating it altogether, the aft mast rig squarely minimizes or completely solves the problems associated with battens.[citation needed] Additionally if there is no mainsail there is difficulty in heaving to or coming to rest with sails set and boat "weathercocked" with bows into the wind.Broadblue Catamarans Ltd. now owns and makes two of the Prout designs, which still come standard with the mast-aft rig.Shotover is a 60-ft long racing catamaran with a 31-ft beam designed by Lock Crowther and built for Sir Douglas Myer.Video in External Links Warick Collins, experimental boat builder, and inventor of both the tandem keel and the universal hull, now uses an aft-mast rig.