Ordnance testing

President Harry S. Truman (in foreground) with unidentified persons throwing a switch during a demonstration of military hardware at Aberdeen Proving Ground in Maryland.

Helicopters engaged in maneuvers during weapons demonstrations at the U.S. Marine base at Quantico, Virginia. President Harry S. Truman (seated, first row, fourth from left) and other unidentified military dignitaries look on.

Helicopter (in the distance) engaged in maneuvers during weapons demonstrations at the U.S. Marine base at Quantico, Virginia. President Harry S. Truman (not pictured) attended this event.

Helicopters flying during a weapons demonstration in Quantico, Virginia. President Harry S. Truman attended this event which was staged by the United States Marine Corps. All are unidentified.

Helicopters engaged in maneuvers during a weapons demonstration at the United States Marine base at Quantico, Virginia, as President Harry S. Truman (standing) and other unidentified dignitaries look on.

President Harry S. Truman (fourth from right) watching a weapons demonstration staged by the United States Marine Corps in Quantico, Virginia. Others are unidentified.

President Harry S. Truman (first row, second from left) at Quantico, Virginia for weapons demonstrations staged by the United States Marine Corps. Others are unidentified.

President Harry S. Truman peering through binoculars, with other dignitaries, watching a weapons demonstration involving amphibious helicopter landings at the United States Marine base at Quantico, Virginia. Seated behind Truman in the second row are, from left to right: General Harry Vaughan, Charles Murphy, and Press Secretary Charles Ross. Seated in the fourth row, behind Mr. Murphy is Joseph Feeney. All others are unidentified.

Helicopters engaged in maneuvers during weapons demonstrations at the U.S. Marine base at Quantico, Virginia. President Harry S. Truman (seated, first row, fourth from left) and other unidentified military dignitaries look on.