Bulbous bows were developed in the 1950’s for large cargo vessels, to improve their penetration of the water, and reduce fuel consumption. The underwater bulb creates a wave 180 degrees out of phase with the original bow wave. This cancels or reduces the bow wave. The first merchant vessel with a bulbous bow was the <i>Yamashiro Maru</i> delivered in November 1963 by the Mitsubishi Heavy-Industries, Ltd. Nagasaki Shipyard in Japan.<ref> Ripples in Time, Bulbous Bow – Introduction of wave-making resistance reduction technology, http://www.nykline.co.jp/english/seascope/200010/</ref> Today all the largest ships, including Nimitz-class aircraft carriers, have bulbs.<ref> Reagan Takes a Bow, http://www.nn.northropgrumman.com/Reagan/About_the_ship/Bow.htm</ref>