300 fighter aircraft on 6 June 1944 to contest the D-day landings. The Western Allies amassed 12,837, including 5,400 fighters. The air fleet was particularly weak in night fighter units. Given the low priority for their production, Sperrle went for periods with no night–fighting capabilities despite the crucial geographical position of his air fleet and the exposure of important French industries to night attack. The diversion of resources extended to anti-aircraft artillery. On 14 May 1944, the OKL cancelled an order to divert five heavy and four light or medium batteries, each from Luftflotte 1 and 6, to Sperrle and instead rerouted them to Luftflotte Reich. Sperrle did retain the III Flak Corps which could be used in ground combat. Another facet of the air war was the night offensive against Germany. Bomber Command's area attacks against German industrial cities enraged Hitler and he ordered Sperrle to use Peltz's bombers to strike back. Sperrle's air fleet was reinforced on Göring's orders for the purpose of bombing London. The offensive was named Operation Steinbock and began in January 1944. The operational aspects were devised by Peltz. He remarked to Göring that he would need any aircraft capable of carrying a bomb. By December 1943, Peltz assembled 695 operational aircraft before the offensive. Of the aircraft, 467 were bombers, 337 of them operational. On 20 January 1944 this increased to 524, with 462 combat ready. Peltz was subordinated to Göring, bypassing Sperrle, who Hitler and Göring regarded as sybarite by this stage. The feeble offensive was mocked by the British, and Peltz' forces incurred a 10 percent loss rate per sortie, for little military gain and 329 bombers were lost. The offensive wasted the last German bomber reserves. The losses were a blow to Sperrle. He had wanted to use his bomber forces to attack the invasion forces during the night at the landing grounds and the embarkation points in England. Hitler and Göring rejected this strategy as "too passive". Normandy and dismissal Sperrle's air fleet Enigma signals had been cracked and ULTRA codebreakers from Bletchley Park deciphered signals sent by Luftflotte 3 headquarters to the OKW. Reading the reports, Allied intelligence deduced that the bombing operations against bridges, west of the Seine, and fighter activity between Mantes and Le Mans, had convinced the air fleet staff the invasion would take place in the Pas de Calais. The air fleet reports, dated