Radar System Engineering

16 INTRODUCTION [SEC.1°7
Microwave Committee persuaded the Massachusetts Institute of Technology
to accept the responsibility of administering the new laboratory,
The Radiation Laboratory, as it was named, opened its doors early in
November 1940. The director of the laboratory throughout its 62
months of life was Dr. L. A. DuBridge.
The Army and Navy development laboratories were glad to depend
on the new Radiation Laboratory for an investigation of the usefulness
for radar of the new microwave region of the radio spectrum. They were
fully occupied with the urgent engineering, training, and installation
problems involved in getting radar equipment that had already been
developed out into actual military and naval service. At the end of
1940, the use of microwaves for radar purposes seemed highly speculative,
and the Service laboratories quite properly felt it their duty to concentrate
on radar techniques that had already been worked out successfully.
During 1941, while the Navy was installing long-wave search radar
and medium-wavelength fire-control radar on ships of the fleet, and the
Army was sending out Signal Aircraft Warning Battalions equipped with
the SCR-270 and antiaircraft batteries with the SCR-268, not a single
item of radar equipment based on the new microwave techniques was
delivered for operational use. However, development work at the
Radiation Laboratory had broadened far beyond the two specific projects
suggested by the British Technical Mission, and microwave equipment
was showing great promise for many wartime uses.
A few important dates will indicate the way in which this development
was proceeding. On Jan. 4, 1941, the Radiation Laboratory’s first
microwave radar echoes were obtained. A successful flight test of a
working “breadboard” model of an airborne radar intended for AI use
was made on March 10, in a B-18A furnished by the Army Air Corps.
In this fight it was found that the equipment was extremely effective in
searching for ships and surfaced submarines at sea.
In the late spring of 1941, an experimental microwave sea-search
radar equipped with a PPI was installed on the old destroyer U.S.S.
Semmes. On June 30, the Navy let the first production contract for
microwave radar equipment based on the work of the Radiation Laboratory.
This was for a production version of the set that had been demonstrated
on the Semmes.
At the end of May, a prototype of the microwave antiaircraft position
finder developed at the Radiation Laboratory was in operation. It
accomplished the then-astonishing feat of tracking a target plane in
azimuth and elevation wholly automatically.
These and other early successes led to an increasing Service interest in
microwave radar, which had seemed so speculative a venture in 1940.
The tremendous expansion of the development program can be measured