Here are some images of Trumpeter Models 1/24 scale Supermarine Spitfire Mk VI.
From Wikipedia"
At the time that the Mk V was placed in production there were growing fears that the Luftwaffe were about to start mass-producing very high flying bombers such as the Junkers Ju 86,
which could fly above the reach of most fighters of the time. It was
decided that a new Spitfire variant would be required with improved high
altitude performance. During a meeting held at the RAE at Farnborough
on 17 February 1941 the Air Ministry asked "that a Spitfire should be
provided with a pressure cabin capable of maintaining a pressure
differential of 1 lb per square inch at 40,000 feet." A Marshall-manufactured
compressor was to be used, and it was agreed that the sliding canopy
could be replaced by one which could not be slid open, as long as it
could be jettisoned by the pilot.
The pressurised cabin was used to counter the physiological problems encountered by pilots at high altitudes.
The cabin was not like the fully pressurised cabin of a modern
airliner; the pressure differential provided by the modified cockpit of
the VI was only two pounds per square inch (which was double the Air
Ministry requirement).
To achieve this, the forward and rear cockpit bulkheads were completely
enclosed, with all control and electrical cables exiting though special
rubber sealing grommets. In addition, the side cockpit door was
replaced with alloy skin and the canopy was no longer a sliding unit:
externally there were no slide rails. Once the pilot was in, the canopy
was locked in place with four toggles and sealed with an inflatable
rubber tube. It could be jettisoned by the pilot in an emergency.
The windscreen of production Mk VIs was the same as the type fitted to
the Mark III and some Mk Vs although it was fitted with an inward
opening clear-view panel on the port quarter pane.
The effect was to make 37,000 ft (11,000 m) seem like 28,000 ft
(8,500 m) to the pilot, who would still have to wear an oxygen mask.
Pressurisation was achieved by a Marshall-manufactured compressor
located on the starboard side of the engine, fed by a long intake below
the starboard exhaust stubs. Mk VIs were built with the Coffman
cartridge starter, with a small teardrop fairing just ahead of the
compressor intake.
The engine was a Rolls-Royce Merlin 47 driving a four-bladed Rotol
propeller of 10 ft 9 in (3.27 m) diameter; the new propeller provided
increased power at high altitudes, where the atmosphere
is much thinner. To help smooth out airflow around the wingtips the
standard rounded types were replaced by extended, pointed versions
extending the wingspan to 40 ft 2 in (12.2 m). Otherwise the wings were Type B.
The maximum speed of the Mk VI was 356 mph (573 km/h) at 21,800 ft
(6,600 m). However, because of the limitations of the single stage
supercharger, at 38,000 ft (12,000 m) the maximum speed had fallen away
to 264 mph (425 km/h). The service ceiling was 39,200 ft (11,900 m).
The threat of a sustained high altitude campaign by the Luftwaffe did not materialise and only 100 of the Mk VIs were built by Supermarine. Only two units, 124 Squadron and 616 Squadron, were fully equipped with this version, although several other units used them in small numbers as a stop-gap.
More often than not, the Spitfire VIs were used at lower altitudes
where it was outperformed by conventional Spitfires. At high altitudes
it was discovered that modified Spitfire Vs could perform almost as well
as the Mk VI. At low levels, especially, pilots were often forced to
fly with the canopy removed because the cockpit would get uncomfortably
hot and they were not confident it would be possible to jettison the
canopy in case of an emergency.
In 1943 five Spitfire VIs (BS106, BS124, BS133, BS134 and BS149) were converted to improvised PR Mk VIs by 680 Squadron
in Egypt. These aircraft had been "tropicalised" using the same bulky
Vokes filter and other equipment used by Spitfire VB Trops, as well as
being painted in a "desert" camouflage scheme.
By the time these aircraft arrived they were no longer required to intercept high-flying Junkers Ju 86P
reconnaissance aircraft although there was a need for a pressurised RAF
photo reconnaissance aircraft to carry out missions over Crete and the rest of Greece.
103 MU at Aboukir carried out the modifications by removing the
armament and installing vertical F8 cameras in the rear fuselage. These
Spitfires were used a few times in April and May 1943 but were withdrawn
from service by August. They were the first pressurised PR Spitfires.
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