History of Sussex airfields around Sussex. During the lead-up to the D-Day landings, the people of Sussex were witness to the build-up of military personnel and materials, including the assembly of landing crafts and construction of Mulberry harbours off the county's coast. Five new airfields were built to provide additional support for the D-Day landings, four near Chichester and one near Billingshurst. A legacy of the D-Day landings are the sections of Mulberry harbour that lay broken and abandoned on the sea floor off the coast, of Selsey Bill, having missed the invasion. Sussex was an industrial county, from the stone age, with
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