When the United States entered World War II in December 1941, the Coast and Geodetic Survey Corps again suspended its peacetime activities to support the war effort, often seeing front-line service. Over half of all Coast and Geodetic Survey officers were transferred to the U.S. Army, U.S. Navy, U.S. Marine Corps, or United States Army Air Forces, seeing duty in North Africa, Europe, the Pacific, and the defense of North America as artillery surveyors, hydrographers, amphibious engineers, beachmasters (i.e., directors of disembarkation), instructors at service schools, and in a wide variety of technical positions. They also served as reconnaissance surveyors for a worldwide aeronautical charting effort, and a Coast and Geodetic Survey officer was the first commanding officer of the Army Air Forces Aeronautical Chart Plant at St. Louis, Missouri. Three officers who remained in Coast and Geodetic Survey service were killed during the war, as were eleven other Survey personnel.