‘Fighter pilots of every nationality thought the Spitfire Mk IX was the best close-in fighter of them all,’ AVM ‘Johnnie’ Johnson.
The following article contains excerpts from Adam Lunney’s book We Together, 451 and 453 Squadrons at War.
Reginald J. Mitchell created the Supermarine Spitfire, first as a private project with a strong focus on the aim to give a higher performance than had been previously accomplished by the F.7/30 design. The parallel development of the Rolls-Royce Merlin and Griffon engines became an essential element of the Spitfire story, along with a further drive to maximize the capabilities of those engines.
The Mk I, Mk V, Mk VII, Mk IX, and Mk XIV were the most significant marks numerically, with the Mk V (Merlin 45) and Mk IX (with Merlin 61 and two-speed/two-stage supercharger) accounting for more than half of the overall output.
The capture of an Fw 190A belonging to JG26 on Jun. 23, 1942, led to the production of the Type 361 Mk IX Spitfire. This was equipped with a 60-series Merlin engine, a stronger airframe, and a four-bladed propeller. There were several variations created, including a high-level version with extended wingtips and a low-level version with clipped wings. A slightly longer nose was required for the 6o-series Merlin, but this was not a problem, and the better engine more than made up for any concerns.
For improved performance, these 6o-series Merlins also featured a two-speed, two-stage supercharger, along with greater settings and customization options. A further ten gallons of fuel could be carried by aircraft, extending its range slightly, and 5,665 of them were made. A and B were once used to distinguish between the wing armaments on early Spitfires, but for the Mk IX, they stood for the installation of various Merlin models.
In July 1942, the 64 Squadron became the first operational squadron to have Mk IXs. For the benefit of those piloting the Mk IX, it took the place of the Mk V, which the Focke-Wulfs were outperforming in the cross-Channel fighter sweeps that both sides were conducting. As a result, the Luftwaffe was caught off guard multiple times. They were expecting an Mk V performance but ended up facing an Mk IX, and it is difficult to tell the difference between the two until you are well within shooting distance.
The German pilots were thus faced with a choice: risk a thrashing by presuming they were up against the lesser Mk Vs and finding out the truth after it was too late, or cautiously regard all Spitfires as Mk IXs. The Allies, however, had no such problems because an Fw 190 and Bf 109 looked very different from one another, and combat could be avoided if the Allies’ pilots were in a weaker position.
An Mk IX equipped with a 61-series Merlin was flown against the captured Fw 190A in the same month. The test revealed that the Spitfire was typically superior, although by a narrow margin, at various altitudes, where the speed difference was less than 10 mph. Due to its greater acceleration, the Fw 190A was marginally better in a climb but not noticeably so, although it was better in a dive, especially in the beginning.
The role of the Fw 190A was far superior to that of the Mk IX, and the overall maneuverability was superior, except in the case of turning circles, where the Mk IX could get inside the Fw 190A for the all-important killing shot. However, one of the Spitfire’s most recognizable characteristics was its ability to turn, which skilled Luftwaffe pilots would have undoubtedly avoided at all costs in any event. Allied pilots were forewarned to expect this maneuver since the Fw 190A had the ability to escape a Spitfire by performing a flick-roll in the opposite direction to the angle of attack and then diving away.
All Spitfire pilots received a directive in August 1942 outlining how to handle the new threat while flying. The instruction in paragraph two of the document stated: “To defeat this aircraft and to avoid casualties on our side, our aircraft must fly as fast as possible whenever they are in the combat zone.” The document recognized that pilots had previously been instructed to economize and save fuel ‘but it is essential, as soon as they are liable to be detected, that they open up to maximum power for duration flying’.
Pilots were advised to avoid cruising when there was a chance of engagement since the Spitfire’s acceleration is quite poor. After more safety advice, the instruction concluded, ‘when in the vicinity of Huns, fly maximum everything and in good time’. A notice distributed to Spitfire Mk V pilots in the Middle East titled ‘Who’s Afraid of the Little Focke Wulf’ a notice given to Spitfire Mk V pilots in the Middle East, echoed these directives and emphasized the Spitfire’s superior turning performance over the Focke-Wulf: ‘The Spitfire V’s only tactical advantage over the F.W. 190 in the air is its ability to turn in a smaller circle, but that’s a lot’.
In January 1943, the first Mk IXs were delivered to squadrons stationed in the Middle East and the Mediterranean. The Mk IX had the ability to carry bombs and was frequently used as a fighter bomber, but it was not allowed to do so in conjunction with a centerline bomb or the 90-gallon “jet” or “slipper” tank. This restriction was lifted in September 1944, but only if the Mk IX was fitted with Mk VIII wheels and tyres and could only take off at a maximum weight of 8,700 lb from a smooth surface. The directive also warned pilots that dive-bombing was still “limited to straight and level flight with the drop tank,” and that the drop tank should be ejected before attempting it.
Many pilots appear to view the Mk IX as the pinnacle of Spitfire evolution. Fighter pilots of all nationalities believed the Spitfire Mk IX was the best close-in fighter of them all, according to AVM ‘Johnnie’ Johnson, who stated that. In a letter to AVM Johnson, another pilot was cited as saying: “I flew most of the various marks of Spitfires, but I felt sort of invincible in the Spitfire Mk IXB. It was a beautiful aeroplane and I was very happy to fly and fight with her.’
We Together, 451 and 453 Squadrons at War is published by Mortons Books and is available to order here along with many other beautiful aviation books.
Photo by Alan Wilson from Stilton, Peterborough, Cambs, UK via Wikipedia, Crown Copyright
