The COLUMBIA has been designed as a high performance, plan­ning launch with very generous waterline beam to give maxi­mum stability and hull lift. The Columbia has a very flat shaft angle on single installation or twin installations for maximum pro­peller efficiency. The shaft angle for a single installation is ap­proximately 9° depending on engine type. Weight is concentrated amidships with the engine, fuel and water to keep the craft in ideal trim without the necessity of trim tabs. The vessel also fea­tures a deep keel to enhance seakeeping ability and give protec­tion to the propeller and rudder. The proven design with the gen­erous freeboard forward ensures an extremely dry vessel able to withstand rough conditions with ease.

There are various cabin layouts shown on the plan and these are shown on the study print. All versions have a flying bridge as this vessel has been specifically designed to take the weight of a bridge well above the waterline. The construction is of double diagonal planking or sheet plywood with 2 skins of ^_1/2" (12mm) on the bottom and 2 skins of ^3/4" (9mm) on the sides. These are over frames at approximately 3ft (914mm) centres with laminated fore and aft stringers, chines, laminated gunwales etc. for maxi­mum strength with minimum weight. The keelson and deadwood, stem etc. are strongly constructed to give an extremely rigid back­bone down the centre of the vessel. A 275 h.p. Volvo with 2 to 1 reduction gives a top speed of 21.5 knots in the 40ft version. Twin 165 h.p. Volvo diesels give a top speed of 23 knots. A 8V71 turbo-charged GM a top speed of 27 knots in the 40 footer. Per­formance figures given on request.

The plan includes FULLSIZE TEMPLATES of the frames, stem etc. plus full working drawings with dimensions given in both metric and imperial.