Supermarine Spitfire. At Royal Air Force's service. Part eight. The Battle of Malta, part two.

 

This is a direct continuation from our previous post.
When the Spitfires were being delivered via aircraft carrier to Malta, the situation reached a point when it was considered dangerous for the carriers to operate on the western Mediterranean region, fearing U-boat and Luftwaffe attacks, so from late October to November 1942 a total of twelve Spitfire Mk. Vc were equipped with a single 170 gallon drop tank and flew direct from Gibraltar to Malta, covering a distance of 1.000 miles (1609.34 Km) in a ferry flight which lasted more than 5 hours.
All those Spitfires fought, and eventually won, the constant aerial attacks from the Luftwaffe and the Regia Aeronautica on Malta. The most successful Spitfire pilot in Malta was the Canadian Plt. Off. George Beurling of No. 249 Squadron, who shot down 26 and a third German and Italian aircraft between June and late October 1942.
It was there, in Malta, where the Spitfire was modified to carry underwing bombs. One machine numbered EP201 from No. 229 Squadron was fitted with one 250 lb bomb under each wing in September 1942 and were employed as improvised bombers to raid fortifications and airfield in Sicily, where their bombs were released at 7,000 feet (2.134m) diving at an optimum 60º angle.

The Spitfire Mk. VI was a high altitude variant designed to combat the Luftwaffe high-altitude bombers, such as the Junkers Ju.86P which, in 1940, could achieve higher altitudes than most fighters of the time, so it was decided that a new Spitfire variant would be needed.
During a meeting the Air Ministry asked for a Spitfire provided with a pressure cabin capable of maintaining high pressures at high altitudes.
That cabin was used to counter the physiological problems found by pilots at high altitudes and it was designed to be locked with four toggles and sealed with an inflatable rubber tube. It could be jettisoned by the pilot in case of emergency. The windscreen was the same as the ones from Mk. III and some Mk. V. 
It was powered by a Rolls-Royce Merlin 47 driving a four-bladed propeller and featured extended and pointed versions of the B-Type wings with an extended wingspan.
However, the threat of the Luftwaffe did not come to fruition and only 100 Mk. VI were manufactured by Supermarine. Eventually only two squadrons, Nos. 124 and 616 were fully equipped with the Mk. VI, albeit many other units employed the type in small numbers as an interim fighter, when transitioning to other marks of the Spitfire or other fighters. 
In most of the cases the Mk. VI were employed at low altitudes, where it was discovered that any given Mk. V could outperform the Mk. VI and, at those altitudes, pilots often flew without the canopy (it was removed before flight) because the cockpit got uncomfortably hot and they were reluctant about its capacity to jettison in case of emergency. 

Sources:
1st Signal Squadron - Aircraft In action 39 - Supermarine Spitfire in Action
2nd https://en.wikipedia.org/wiki/Supermarine_Spitfire_operational_history#Mediterranean_service
3rd https://en.wikipedia.org/wiki/Supermarine_Spitfire_(early_Merlin-powered_variants)