Piercing the Fog - Air Force Historical Studies Office

Piercing the Fog
Eighth and Ninth Air Forces were heavily involved in these operations, the
latter almost exclusively so. While their B-17s and B-24s continued to attack
German aircraft factories through much of April, in May their attention turned
to marshaling yards and airfields in France, Belgium, and the western part of
Germany. Beginning on May 21, VIII Fighter Command's P-47~ and P-5 1 s
joined the Ninth Air Force in extensive attacks on rail bridges. As part of
Operation FORTITUDE, the deception plan to convince the defenders that the real
attack would come in the Pas de Calais region, twice as many bombs were
dropped on targets north of the Seine as were dropped to the south. Obviously,
this increased the burden on intelligence as much as it did on operation^.'^^
Despite participation by the heavy bombers and their escorts, Ninth Air
Force made the principal American air contribution to OVERLORD before and
after D-day. As directed by Eisenhower, the Ninth's primary objective was the
German transportation network in France and Belgium. In the two months
before D-day, medium bombers, fighter-bombers, and strafing fighters also
struck more than sixty airfields and sought to neutralize German coastal
batteries. Reconnaissance elements flew more than 400 sorties against gun
emplacements, beach defenses, transportation points, airfields, and other
targets.lM Once the forces were ashore at Normandy, Ninth Air Force became
deeply involved in the collection and analysis of intelligence, including the
establishment of a SIGINT capability and mobile photoreconnaissance and
analysis facilities to meet the demands for immediate responses to fluid combat
situations. During preinvasion operations, however, both the Eighth and Ninth
relied on previously established intelligence organization^.'^^
Photographic reconnaissance remained the primary source for monitoring
static targets such as bridges, marshaling yards, and airfields. Hundreds of
reconnaissance missions had pinpointed virtually every useful target within the
German transportation system. As these targets became the focus of air attack,
aerial reconnaissance and agent reports were the main sources of information
on specific attacks and constituted the means to determine when reattacks were
necessary. ULTRA provided some details on individual targets, but it was more
valuable for its insight on the German assessment of conditions.'68
The location of almost all airfields in northwest Europe had been identified
by a combined Anglo-American section within Air Ministry Intelligence, and
a watch was maintained on them by the airfield section of the CIU as well as by
the French underground. By the spring of 1944, these organizations provided
not only locations but capacities, facilities, and even designations of appropriate
aiming points. At the same time, SIGN followed the movement of enemy
flying units. In the first week of May, ULTRA revealed the installations to which
units from Germany and other regions would move in the event of an invasion.
Two weeks later, it provided intelligence on the distribution of fuel, ammunition,
and Results of the ongoing campaign against German airfields
were revealed by all these sources.
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