from the lack of pressurisation, the Mk VIII differed little from the Mk VII beyond the reshaped fin and pointed rudder. Some early production models had extended wingtips but the majority were fitted with the standard version. According to Supermarine's Chief Test pilot Jeffrey Quill "When I am asked which mark of Spitfire I consider the best from the flying point of view, I usually reply 'The Mark VIII with standard wingtips.' I hated the extended wingtips...They were of no practical value to the Mark VIII and simply reduced the aileron response and the rate of roll." New Zealand ace Alan Peart described the extended wingtips causing structural damage to Mk VII Spitfires in Burma, and being replaced by standard wingtips. There were three sub-variants for low altitude (LF Mk VIII), medium altitude (F Mk VIII) and high altitude (HF Mk VIII) which were powered respectively by the Merlin 66, Merlin 63 and Merlin 70 engines. The F Mk VIII's top speed was at 25,000 ft (404 mph for the LF Mk VIII at and for the HF Mk VIII at 26,500 ft), with a service ceiling of 43,000 ft (41,500 ft for the LF Mk VIII and for the HF Mk VIII). The two main tanks were given an extra 11 gal for a total of 96 gal which, along with the wing tanks, allowed the fighter to fly for a maximum distance of with a full internal fuel load and with a full internal load and a 90 gal drop tank. Provision was made to allow the Mk VIII to carry a single "slipper" drop tank of 30, 90 or 170 gal capacity. With a 170 gal tank, the aeroplane could fly over . When carrying the 90 or 175 gal tank the aircraft was restricted, once airborne and at cruising altitude, to straight and level flight. A maximum external bomb load of 1,000 pounds (1 × bomb attached to the centre bomb-rack plus a bomb under each wing) could be carried. A Mk VIII JF299 was used to experiment with the use of a new cut-back rear fuselage and a "tear-drop" canopy. This was intended to aid pilot visibility; many Spitfire pilots who were shot down were done so by enemies who approached in the aircraft's blind spot. In trials, the new hood design was found to bring about great improvements to all-round visibility and with several