Three hundred and sixty F4U-1As were delivered to the Fleet Air Arm. In British service, they were modified with "clipped" wings ( was cut off each wingtip) for use on British aircraft carriers, although the Royal Navy had been successfully operating the Corsair Mk I since 1 June 1943 when No. 1830 Squadron NAS was commissioned and assigned to HMS "Illustrious". F4U-1s in many USMC squadrons had their arrester hooks removed. Additionally, an experimental R-2800-8W engine with water injection was fitted on one of the late F4U-1As. After satisfactory results, many F4U-1As were fitted with the new powerplant. The aircraft carried in the main fuel tank, located in front of the cockpit, as well as an unarmored, non-self-sealing fuel tank in each wing. This version of the Corsair was the first to be able to carry a drop tank under the center-section. With drop tanks fitted, the fighter had a maximum ferry range of just over .