<p>Airfields were a more difficult class of targets. There were more than 100 usable fields within reach of the Normandy invasion coast. Further, forward airfield repair is easily and quickly done. As a result, a large number of targets had to be hit heavily, and at the last possible moment. It was done primarily by the medium and light bombers of Ninth AF.
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<p>By mid-April the Ninth turned its attention to the Atlantic Wall, the Wehrmacht defense line along the Channel coast. RAF Bomber Command and Eighth AF heavies joined the fray later. Together, they damaged about half of the coastal gun batteries behind the beaches. The RAF's Second TAF sent its Hawker Typhoon fighter-bombers against the German radars; they either destroyed or made inoperable almost every installation in the area. On D-Day the Germans were radar-blind.
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<p>At least eight reconnaissance missions were flown each day before the invasion to photograph the changing appearance of the beaches. Pilots of Second TAF and IX Fighter Command shared those missions, and for deception photographed two sites elsewhere for every Normandy location.
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<p>Most dangerous of the reconnaissance sorties were 11 flown at extremely low level by pilots of the 10th Photo Reconnaissance Group, Ninth AF. Roaring above the beaches at about 15 ft (4.5 m) altitude, these 'Dicing' missions brought back very detailed information about the German beach defenses. The 10th PRG received a Distinguished Unit Citation for its work.
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<p>Meantime, very satisfying results were being obtained in the strategic bombing campaign against oil production and processing, at least at this stage of the assault. Germany drew about half of all its production of fuel from a combination of synthetic gasoline plants and crude oil refineries that had been unwisely concentrated in three areas: Ploesti, Silesia and the Ruhr.
