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

RADIO AND RADIO-WEATHER PREDICTING 403
that of the Bat. But the decision had been made and only the Bat went
overseas. In the final months, land-based Navy patrol squadrons in the
Pacific made effective use of it against Japanese naval and merchant ship.
ing and against land targets in the forward areas.'°2
Complex and formidable as the Pelican and Bat seemed at the time,
they were but pale prototypes of the missiles to come in the postwar years.
RADIO AND RADIO-WEATHER PREDICTING
An important weapon in subduing the German submarine menance
was the high-frequency direction finder, called "Huff-Duff," a play on its
initials, h—f—d—f. Its progenitor was the radio compass or direction finder
designed by Frederick A. Koister of the Bureau in
When early in the war the Allies established the convoy system for
the Atlantic crossing, the U-boats began stalking the convoys in wolf packs,
using their wireless to direct the group operations. The wireless gave away
their positions to British and American Huff-Duff stations and allowed radar-
equipped planes from land bases or carriers to find them.
Errors in accuracy in existing Navy, Signal Corps, and commercial
directi&n finders sometimes caused the search planes to miss the enemy packs.
In April 1941, NDRC requested the Bureau to study the errors in high-
frequency finders and determine techniques for measuring these errors. Out
of the research came new techniques for assessing a variety of errors possi-
ble in the direction finders themselves, and correlation of these errors with
the influence of atmospheric disturbances on the finders. The results were
set out in two important papers prepared for NDRC, one by Diamond, Lyons,
and Post on "High-frequency direction finder apparatus research by the
NBS," the other by Kenneth Norton on "The polarization of d•owncoming
ionospheric radio waves." The latter paper NDRC acclaimed as "a
thorough development of the physics of ionosphere reflections [that] has
become a classic on the subject," and much of the subsequent research on
direction finders, both in NDRC and in Allied research centers, was based
on the fundamental theories set down in these two reports.'°4
By June 1943 Huff-Duff, together with Asdic, radar, Loran, sonar, and
voice and radio communication, had driven the wolf packs from the North
102
NBS War Research, p. 34; Boyce, New Weapons for Air Warfare, Pp. 225—235.
103
See ch. III, p. 142.
See C. C. Suits, C. R. Harrison, and L. Jordan, eds., Applied Physics, Electronics,
Optics, Metallury (OSRD, Science in World War II, Boston: Little, Brown, 1948),
pp. 135—136, 140.