Piercing the Fog - Air Force Historical Studies Office

Piercing the Fog
Allied understanding of enemy Y-Services dependent on not only interception
of Japanese messages, but also the ability to decrypt the system in use?3
The Japanese at times gained valuable and specific air information from
captured flyers, as could be seen in the February 1944 report to Tokyo on Allied
air strength in North Australia. That Japanese report, based upon interrogation
of a first lieutenant copilot of a B-24, identified the AAF’s 380th Group
commanded by a Colonel Miller (the 380th Bombardment Group commanded
by Col. William A. Miller) with assigned 528, 529, 530, and 531 squadrons
(actually, the 328, 329, 330, and 331 squadrons) at RAAF Long and RAAF
Fenton, near Darwin. The Japanese also understood that fifty planes were in the
group. To that, Allied analysts commented in the SIB synopsis, “The enemy’s
information is high grade.” The knowledge that the Japanese had of the 380th’~
home station triggered from Allied analysts warnings of a possible Japanese
parachute assault on the airfields. Both Long and Fenton were in range of
Japanese transport aircraft, and available fragmentary evidence indicated the
presence of the Zst and 2d Raider Groups, both parachute units, in New Guinea.
(The 1st Raider Group, also known as the 1st Parachute Brigade, had captured
Palembang airfield on Sumatra in February 1942.) The Japanese made no
parachute attack on the Australian airfields, but Darwin was the subject of aerial
bombardment on a number of occasions at about the same time.’4 POW
interrogations yielded other data as well.
At about the same time that they captured the lieutenant copilot of the
B-24, the Japanese got hold of another American, a colonel, commander of a
heavy bomber group in the Thirteenth Air Force. This unfortunate man faced
questioning first at Rabaul, then possibly in New Guinea, before Tokyo directed
his transfer there. In the process of interrogation, the Japanese gained informa-
tion on aircraft loss rates, personnel, flying accidents, air-sea rescue procedures,
and the development and possible use in the Pacific of B-29s. Willoughby’s SZB
for February 24, 1944, cited the information Japan had gained from the
American officer regarding AAF strength in the SOPAC theater as of about
December 30, 1943:
Aircraft Types Japanese Information Actual Strength
P-38, P-39, P-40, and
Spitfire
200 190
B-25 60 74
B-24
B-24, radar equipped*
96
- 8
146
- 8
Total 364 418
*Bombers equipped for low-level sea search and attack of Japanese merchant
shipping.
294