HMNB Portsmouth the military and naval units destined for Sword Beach on the Normandy coast as a part of Operation Overlord and the D-Day landings on 6 June 1944. Troops destined for each of the landing beaches left from Portsmouth aboard vessels such as the armed merchant cruisers HMCS "Prince Henry" and HMCS "Prince David", escorted by the Canadian destroyers HMCS "Algonquin" and "Sioux". The majority of the naval support for the operation left from Portsmouth, including the Mulberry Harbours. Boathouse 4 (built around the start of hostilities) contributed to the construction of landing craft and support vessels as well as more
Australian contribution to the Battle of Normandy German aircraft. No. 456 Squadron also formed part of the force that provided air defence for the invasion area at night. In addition, about 200 Australian pilots were spread across the dozens of RAF fighter and fighter-bomber units that supported the landings. A small number of Australian aircrew also served in RAF reconnaissance units and 2TAF's light bomber squadrons, which also saw combat over France on D-Day. The three Australian squadrons assigned to Coastal Command flew only a small number of sorties on 6 June as few German submarines or E-boats put to sea. About 500 RAN personnel served on