The Landing Craft, Tank (Rocket) was a British conversion based on an LCT(2) or LCT(3). The craft fired around 1,000 3-inch rockets to a range of 3,500 yards. The rockets were mounted at a fixed 45-degree angle, and could not be aimed other than by the direction of the ship, whose crew used radar to ensure the bombardment fell on target. In normal use the rockets would cover an area something like 700 yards deep by 150 yards wide.
Above: LCT(R) 481 off Utah Beach, turning back after having fired its rockets just before H-Hour. The highest feature on the vessel, on the left (stern) end, is the radar used for determining the range to the target. This was essential to accurate firing, as the individual rocket-projectors were at a fixed angle. This particular LCT(R) had been converted by the British but was under a US Navy crew on D-Day. (Photo: US Navy photos at US National Archives)
These craft were scheduled to fire their rockets in the final minutes before the assault troops went ashore. Individual rockets were not aimed at specific targets: it was an area effect weapon, relying on the volume of fire to encourage enemy troops to keep their heads down. Just under half the LCT(R)s present for D-Day were transferred by the British to the US Navy for use at Omaha and Utah Beaches. Generally the Landing Craft, Tank (Rocket) was praised for its effectiveness on D-Day. In some cases they were judged (not always fairly) to have fired too close to friendly forces.