6 June, 1944 D-Day
"Soldiers, sailors, and airmen of the Allied Expeditionary Force! You are about to embark upon the great crusade toward which we have striven these many months. The eyes of the world are upon you. The hopes and prayers of liberty-loving people everywhere march with you." - Gen. Eisenhower's Order of the Day
114 Allied planes
(figures above taken from Chronology of WWII: The Day By Day Record 1939-1945)
"Casualties" meaning a total of dead, wounded, and/or missing/captured. A good breakdown is here.