Donald McKay - McKay's Design Practices

McKay's Design Practices

McKay's designs were characterized by a long fine bow with increasing hollow and waterlines. He was perhaps influenced by the writings of John W. Griffiths, designer of the China clipper Rainbow in 1845. The long hollow bow helped to penetrate rather than ride over the wave produced by the hull at high speeds, reducing resistance as hull speed is approached. Hull speed is the natural speed of a wave the same length as the ship, in knots, where LWL = Length of Water Line in feet. His hulls had a shorter afterbody, putting the center of buoyancy farther aft than was typical of the period, as well as a full midsection with rather flat bottom. These characteristics led to lower drag at high speed compared to other ships of similar length, as well as great stability which translated into the ability to carry sail in high winds (more power in extreme conditions). His fishing schooner design was even more radical than his clippers, being a huge flat-bottomed dinghy similar in form to 20th century planing boats. These design changes were not favorable for light wind conditions such as were expected on the China trade, but were profitable in the California and Australian trades.

Pan Am named one of their Boeing 747s Clipper Donald McKay in his honor.