Bombing of Normandy began around midnight with more than 2,200 British, Canadian, and American bombers attacking targets along the coast and further inland.[42] The coastal bombing attack was largely ineffective at Omaha, because low cloud cover made the assigned targets difficult to see. Concerned about inflicting casualties on their own troops, many bombers delayed their attacks too long and failed to hit the beach defences.[94] The Germans had 570 aircraft stationed in Normandy and the Low Countries on D-Day, and another 964 in Germany.[42]
Minesweepers began clearing channels for the invasion fleet shortly after midnight and finished just after dawn without encountering the enemy.[95] The Western Task Force included the battleships Arkansas, Nevada, and Texas, plus eight cruisers, 28 destroyers, and one monitor.[96] The Eastern Task Force included the battleships Ramillies and Warspite and the monitor Roberts, twelve cruisers, and thirty-seven destroyers.[6] Naval bombardment of areas behind the beach commenced at 05:45, while it was still dark, with the gunners switching to pre-assigned targets on the beach as soon as it was light enough to see, at 05:50.[97] Since troops were scheduled to land at Utah and Omaha starting at 06:30 (an hour earlier than the British beaches), these areas received only about 40 minutes of naval bombardment before the assault troops began to land on the shore.[98] Some of the landing craft had been modified to provide close support fire, and self-propelled amphibious Duplex-Drive tanks (DD tanks), specially designed for the Normandy landings, were to land shortly before the infantry to provide covering fire. However, few arrived in advance of the infantry, and many sank before reaching the shore, especially at Omaha.[99][100]
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Omaha, the most heavily defended beach, was assigned to the 1st Infantry Division and 29th Infantry Division.[149] They faced the 352nd Infantry Division rather than the expected single regiment.[150] Strong currents forced many landing craft east of their intended position or caused them to be delayed.[151] For fear of hitting the landing craft, American bombers delayed releasing their loads and, as a result, most of the beach obstacles at Omaha remained undamaged when the men came ashore.[152] Many of the landing craft ran aground on sandbars and the men had to wade 50-100m in water up to their necks while under fire to get to the beach.[100] In spite of the rough seas, DD tanks of two companies of the 741st Tank Battalion were dropped 5,000 yards (4,600 m) from shore, and 27 of the 32 flooded and sank, with the loss of 33 crew.[153] Some tanks, disabled on the beach, continued to provide covering fire until their ammunition ran out or they were swamped by the rising tide.[154]
Casualties were around 2,000, as the men were subjected to fire from the cliffs above.[155] Problems clearing the beach of obstructions led to the beachmaster calling a halt to further landings of vehicles at 08:30. A group of destroyers arrived around this time to provide fire support so landings could resume.[156] Exit from the beach was possible only via five heavily defended gullies, and by late morning barely 600 men had reached the higher ground.[157] By noon, as the artillery fire took its toll and the Germans started to run out of ammunition, the Americans were able to clear some lanes on the beaches. They also started clearing the gullies of enemy defences so that vehicles could move off the beach.[157] The tenuous beachhead was expanded over the following days, and the D-Day objectives for Omaha were accomplished by D+3.[158]