Measures for Progress: A History of the National Bureau of Standards

A GUIDED MISSILE CALLED THE BAT 399
might be retrieved from the beach or beachhead. The same negative deci-
sion withheld use of the director mechanism for toss bombing.
So great were precautions to keep the proximity fuze out of enemy
hands that it was not officially released for general use in the theaters until
December 1944, 6 months after D-day. Even then its use was forbidden
where enemy observers might identify the nature of the fuze. Among added
precautions, the fuzes in rockets for use against aircraft were designed to
destroy themselves before striking the ground in case of a miss, and bombs
and rockets for air-to-ground strikes had an auxiliary contact fuze that func-
tioned on impact in case of failure of the VT fuze. The single exception to
the early restriction was use of the shell fuze in the British defense against the
German V—i robot bomb in the summer of 1944.
Following instruction courses given at the Bureau and at Aberdeen
Proving Ground to Navy and Air Force teams, the first major combat use
of the bomb fuze, by the 7th Air Force, occurred during the preinvasion
bombardment of Iwo Jima in February 1945. in Europe both bomb and
rocket fuzes, the latter in the new 4.5-inch rocket carried by fighter planes,
were first used against German flak batteries and other ground targets in
ApriL92
In 1944, as large-scale production was reached, over 8 million radio
proximity .fuzes were made, almost a quarter of them bomb, rocket, and
mortar fuzes.°3 By then fuze plants were monopolizing 25 percent of the
total facilities of the electronic industry and 75 percent of all molding plastics
firms. And even more sophisticated fuzes were on the way. As produc-
tion slackened with the end of the war, research was resumed in a search for
better components and more versatile fuzes.94
A GUIDED MISSILE CALLED ThE BAT
The Bureau borrowed on the wartime radar research carried out else-
where for its construction of the "Bat," the first fully automatic guided
missile ever used successfully in combat.
The guided missile program began late in 1940 when NDRC initiated
research on a new weapon it believed might be useful to the services, a
Hinman, pp. 36—40; Baxter, pp. 240—241, 234—235.
Of the 8.3 million fuzes produced, 61 percent went to the U.S. Army, 26.7 percent to
the U.S. Navy, and the remaining 12.3 percent to the British armed forces (Baxter, p.
236 n.). It has been estimated that of the fewer than 2 million NBS fuzes made, prob-
ably no more than 20,000, primarily bomb fuzes, were used in the European and Pacific
theaters (Astin, ed., "Bomb, Rocket, and Torpedo Tossing," p. 8).
Baxter, p. 242; Rinehart MS, p. 260.