Exercise Tiger , a training mission for D-Day , took place in April 1944 . More than 700 American servicemen lost their lives in German torpedo boat attack . On April 28 , 1944 , the beaches at Slapton Sands along the south coast of England were being used as a training ground because they provided similar conditions to what American troops would encounter in Normandy less than two months later . Comment: Exercise Tiger revealed some problems that were fixed before actual D-Day invasion .
Exercise Tiger , a training mission for D-Day , took place in April 1944 . More than 700 American servicemen lost their lives in German torpedo boat attack . Comment: Exercise Tiger revealed some problems that were fixed before actual D-Day invasion .