Piercing the Fog - Air Force Historical Studies Office

Piercing the Fog
Special Intelligence Branch designed and had built flak computers that could be
used to determine AA artillery patterns at several altitudes from 15,000 feet to
30,000 feet. These computers aided mission planners in determining the safest
route to a target area. The Special Intelligence Branch also kept close contact
with the Directorate of Communications, whose job included radar countermea-
sures (RCM) analyses. From the data supplied by the communicators, AAFPOA
A-2 prepared radar coverage maps to supplement the flakintel information sent
to field units. To reduce danger to the B-29s on bombing runs over Japan, the
XXI Bomber Command and AAFPOA’s VII Fighter Command cooperated to
reduce Japanese radar coverage.
Beginning in mid-May, the Bomber Command extended RCM flights to
cover much of Japan. First, RCM B-29s picked up radar signals and found their
points of origin by triangulation. Nisei radio operators on board listened to the
associated Japanese radio transmissions to and from the stations. Once the
bomber crews plotted the information, the B-29 command passed the data to
AAFPOA’s VII Fighter Command. Based on information from the RCM
aircraft, P-5 1 s of the 15th Fighter Group struck radar stations on Chichi Jima
with strafing, rocket, and dive-bombing attacks on June 27,28, and 29, 1945.
The weather was too poor to observe results, but the operations highlighted the
prompt exploitation by one air command of intelligence collected by another.66
AAF-Navy cooperation carried out by the Seventh could also be seen in the
aerial minelaying around the Bonin Islands during November and December of
1944. At other times, Seventh Air Force B-24s and P-47s attacked shipping and
Japanese airfields on Iwo Jima, Haha Jima, and the Pagan Islands. Many armed
reconnaissance missions near the Bonins sought targets in those waters. At other
times, Seventh Air Force B-24s and P-38s escorted Navy or AAF reconnais-
sance aircraft overflying Japanese-held islands. On May 25, 1945, VII Fighter
Command and its subordinate units came under control of Twentieth Air Force
as the latter carried out strategic bombing of Japan. From that day, the long-
range P-47s flew more and more frequently against Japanese home island
targets. In mid-July, the remainder of the Seventh became part of General
Kenney’s FEAF on Okinawa. Only at the very end of the war did the Seventh
become an integral air force, able to use intelligence information to plan its own
operations. By then there was no war left to fight.67
In April 1945, JICPOA’s Air Estimates Group moved from Hawaii to
Guam to support the advanced theater headquarters there. That move broadened
the flow of intelligence to the AAF as the XXI Bomber Command received
better and more frequent estimates of Japanese air strength and dispositions in
the home islands. This improved intelligence and resulted in better mission
planning for the remainder of the war. The close proximity to FEAF’s
operations in the Philippines also increased cooperation between JICPOA and
G-2 SWPA in preparation for the final assault on Japan.68
328