F4U-1A (Corsair Mk II): The designation F4U-1A does not appear in lists of Corsair Bureau Numbers and was not in official use, being applied post-war to differentiate mid to late production F4U-1s from the early production variant.
Mid to late production Corsairs incorporated a new, taller and wider clear-view canopy with only two frames, along with a simplified clear view windscreen. The cockpit seat was raised 7 in (180 mm) which, with the wider canopy top section, allowed the pilot better visibility over the long nose. The Plexiglas rear-view windows as well as the one under the cockpit were omitted. The tailwheel strut was lengthened, which also aided the pilot's forward view. These Corsairs were the first "carrier capable" variant and introduced a 6 in (150 mm)-long stall strip just outboard of the gun ports on the starboard wing leading edge and improved undercarriage oleo struts which eliminated bouncing on landing. F4U-1s supplied to the USMC lacked arrester hooks and the tail wheels were changed to a smaller diameter solid rubber type.
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 237 gal (897 l) in the main fuel tank, located in front of the cockpit, as well as an unarmored, non-self-sealing 62 gal (235 l) 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 1,500 mi (2,400 km).