The meticulous planning left nothing to chance, even with the assumption that a foothold would be successfully established by darkness. During the night of D-day, the cruisers would expend an additional 250 shells on interdictory missions, and the destroyers were authorized to fire a total of 300 5-inch rounds on call from the infantry. To help thwart any possible enemy ambitions at dawn of D-plus 1, the cruisers would be prepared to unload 300 shells for interdiction and call fires, while the destroyers stood poised with the same number of high-explosive missiles plus 300 illuminating shells. Other details of the elaborate plan dealt with the coordination of naval gunfire, air, artillery, mortars, and rockets. At certain times, for example, Marine and Navy gunners could fire only below a maximum trajectory of 1100 feet, so that planes, whose minimum altitude was set at 1500 feet, could pass safely over Inchon during strikes on adjacent areas. During those periods when close support Corsairs were scheduled to descend on beachhead targets, all other heavy weapons would fire completely clear of broad circles defining strike areas for the air missions. More tables and instructions in the formidable appendixes of Admiral Doyle’s operation order assigned shore fire control parties their ships and radio frequencies, ships their battery missions and ammunition allowances, and a host of other tasks and responsibilities. _Air Support for Inchon_ Air support, of course, was closely related to naval gunfire planning. After the arrival of CG 1st MAW and his staff at Tokyo on 3 September, part of the group proceeded at once to Itami Air Force Base while General Harris and selected staff members remained at Tokyo for planning conferences. Air support planning for Inchon was based on the decision that the sky over the objective area was to be divided between the organic air units of JTF-7 and X Corps. JTF-7 counted on its fast carrier task force, TF-77, to gain air supremacy and furnish deep support and interdiction strikes. Close support for the landing was to be provided by the two squadrons of TG-90.5, on board the CVEs _Sicily_ and _Badoeng Strait_, which had been the main air components of MAG-33 in support of the 1st Marine Provisional Brigade. In addition, the Attack Force commander could also call upon the aircraft of TF-77 for close support. Organic air support for X Corps was to be the mission of the Tactical Air Control set up under the operational control of the corps commander and the direct command of General Cushman. The inspiration for this organization came from Marine officers on the staff of X Corps. Their suggestions were accepted by General Almond, who used his authority as FECOM chief of staff to put the idea into effect.