Piercing the Fog - Air Force Historical Studies Office

Army Air Forces’ Y-Service
Planning the Defeat of Japan
Shortly after the war began, the Army had created and assigned to the AAF five
signal intelligence companies. The AAF found these companies satisfactory so
long as they worked within the United States, where they served as stationary
operating agencies of numbered air forces. Their primary function was to
intercept encrypted, coded, and voice transmissions; they also performed radio
direction finding. It soon became apparent that these companies could be
valuable overseas in gathering air intelligence; they began moving to combat
areas in 1943, where AAF headquarters attached them to numbered air force
headquarters. Once in the combat areas, the commanders realized that the table
of organization dictated companies that were clumsy and ill-suited to the mobile
type of air warfare of the early 1940s. By the summer of 1943, the AC/AS,
Intelligence staff believed that a number of changes should be implemented. To
start with, Maj. Virgil 0. Johnson returned to Washington from New Guinea
where he had served as a radio intercept expert in General Whitehead’s Fifth
Air Force advanced headquarters. Johnson’s new task was to help formulate
plans for an entirely new AAF radio intercept organization. Both G-2 and the
Signal Security Agency gave initial, informal approval to the undertaking; the
Army’s intelligence staff knew that they needed to make some changes to better
support the field air units, and overseas commanders were anxious to have
better radio intercept operations. Johnson, on his arrival in Washington,
delivered a letter from Whitehead, pleading for much improved support.
Whitehead was not alone, for late in 1943 Brig. Gen. Howard Davidson sent
Hap Arnold a letter from Tenth Air Force in India seeking better intercept
assets. Although Davidson had a radio intercept squadron, it could not do what
he needed because it lacked Japanese language specialists who could translate
and make useful the informaticin overheard by the operators. Davidson closed
his letter by telling Arnold, “The Japanese are great talkers over the radio [while
in flight], but unfortunately we have no way of knowing what they are
saying.”23
The resulting Air Staff actions altered the original companies into what
were known as radio squadrons, mobile-units that could move rapidly with the
area air headquarters and do more of the things that air generals needed. The
new squadrons were larger, acting as would an air force signal intelligence
service or signal security agency unit, providing not only intercept and direction
finding but also translation, analysis, and evaluation for the air commander.
Each squadron served an air headquarters that was unique as to region, mission,
and composition; thus each squadron differed in what it did and how well it did
it. Typical, if one could use that word fur one of these units, was the 1st Radio
Squadron (Mobile), which in August 1943 superseded the 138th Signal Radio
Intercept Company in New Guinea. The squadron was fortunate in that it
inherited much that SWPA’s CB had helped set up for the AAFSWPA
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