Robert Lochner (engineer) harbours to Franklin Roosevelt and Winston Churchill. The decision to go ahead was taken and full-scale trials of the floating breakwater started in April 1944. During the trial, an onshore gale produced heavy seas, but Robert's bombardons calmed the waves effectively. Assembling two Mulberry Harbours the day after the landings on 7 June 1944 was one of the most remarkable engineering feats in history. A total of 1,500,000 tons of harbour equipment had to be taken across the channel in an operation involving 150 Allied tugs, and by D-Day 'plus 12', most of Lochner's concrete breakwaters were in position. On
D-Day (military term) originally set for June 5, 1944, but bad weather and heavy seas caused U.S. Army General Dwight David Eisenhower to delay until June 6 and "that" date has been popularly referred to ever since by the short title "D-Day". Because of the connotation with the invasion of Normandy, planners of later military operations sometimes avoided the term to prevent confusion. For example, Douglas MacArthur's invasion of Leyte began on "A-Day", and the invasion of Okinawa began on "L-Day". The Allies' proposed invasions of Japan would have begun on "X-Day" (on Kyūshū, scheduled for November 1945) and "Y-Day" (on Honshū, scheduled