PATTON'S THIRD ARMY Pre-Operational Phase In Normandy When the Third Army Headquarters landed on French soil, the first thing done was to insure absolute security. In accordance with the plan Overlord, the presence of the Third Army was to be kept secret as long as possible. The idea was to keep the German High Command guessing as to the where- about's of General Patton.During the first days in the Allied invasion, the XIX Tactical Air Command, whose primary job was aerial support for the Third Army, established its own headquarters adjacent to the army headquarters. Their detailed planning then started...