in (7.7 mm) Browning machine guns with 350 rpg. Provision was also made to carry a 30 gal (136 L) "slipper" fuel tank under the fuselage. In June 1942, the first deliveries of the Seafire took place to 807 Squadron. Another front line unit, 801 Squadron operated this version on board from October 1942 through to September 1944. Further development The second semi-naval variant of the Seafire and the first to be built as such, was the Seafire F Mk IIc which was based on the Spitfire Vc. The Vc had several refinements over the Spitfire Vb. Apart from the modifications included in the main batch of Seafire Ibs this version incorporated catapult spools, and a single slinging lug on either side of the fuselage, just behind the engine bulkhead. Three subtypes were produced, the F Mk IIc and FR Mk IIc (fighter reconnaissance), powered by a Merlin 46, and the L Mk IIc powered by a low altitude Merlin 32 specifically manufactured for naval use. This version of the Merlin used a "cropped" supercharger impellor to provide greater power at low altitudes than the standard engines; delivering 1,585 hp (1,182 kW) at 2,750 ft (838 m). Both engine models drove a four bladed 10 ft 9 in (3.28 m) diameter Rotol propeller. Because this version used the "C" wing the Hispano cannon were fed from a 120-round belt magazine, otherwise the armament was the same as that of the Ib; the FR also carried two F24 cameras. After trials of Rocket Assisted Take Off Gear (RATOG - small solid-fuel rocket motors which could be attached to the fuselage or wings of aircraft to help shorten the take-off run) in February 1943, this equipment became a standard fitting available for all Seafires. However, many FAA pilots rarely used RATOG, in part as there was little need for it, and due to the risks posed by asymmetric ignition. The IIc model was the first of the Seafires to be deployed operationally in large numbers, Supermarine constructed 262 of this model and a further 110 being built by Westland, who also built 30 Seafire Mk III (Hybrid) (Mk IIIs without folding wings). Although developed for aircraft carrier use, this version still lacked the folding wings needed to allow them to be used on board some Royal Navy carriers, some of which had small aircraft elevators unable to accommodate the full wingspan of