Spitfire Mk F.IX

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Feb 23, 2014
Katy Texas
Confusion abounds within me, I am no lover of the British naming / model numbering.
Is the Mk F.IX the same as a Mk IXc? the F.IX (as I understand it) is the basic IX which for the most part (early IX) are converted from earlier marks such as the V. Is the c wing to be considered a minimum configuration or was the b wing used such as a Vb being upgraded to a IX. I know the Merlin 61 or 63 was used but I can't figure which wing was used. If I read my information correctly MkI, II and V were upgraded to IX status as it was considered the minimum to deal with the Fw190A but the F.IX is an enigma in what it is.... HELP!!!
The Spitfire Mk.IX is nothing more but the Mk.V with new, more powereful Merlin engine ( Merlin 61 or Merlin 63 ), reinforced engine bed and fuselage. The Low altitude Spitfire IX got the Merlin 66 while the high altitude variant the Merlin 70. As memo serves the "F" letter just means the "fighter". So all Mk.IX were the F Mk.IX. In abbreviated form F.IX. Therefore we have the Spitfire F Mk.IX, LF Mk.IX and HF Mk.IX ( shortly - F.IX, LF.IX and HF.IX). Initially Spitfire Mk.IX had the same armament like the Mk.Vb and Mk.Vc. Because the "C" wing was the universal one , the variant was used for the Spitfire Mk.IX initially. This resulted in the Mk.IXc marking. Later the "E" varinat of the wing was introduced. And this resulted in the marking Mk.IXe. The "C" wing had 1x20mm British Hispano cannon and 2x7.7mm Browning II MGs per a wing installed. The "E" wing hosted 1x20mm BH cannon and 1x12.7mm Colt-Browning gun per a wing.

PS. the "C" wing as the universal one could have three different sets of the armament installed. Just the one mentioned above was the most popular.

the link may be useful as well ...

At its simplest I agree with Wurger.

BUT you may come across one designation to confuse you. The "Spitfire IXB" is often found in squadron records in early 1944. This arose when the low level Mk.IX with the Merlin 66 was introduced in early 1944. It was explained this way in an 18 page article in Air Enthusiast in 2001 titled "Five to Nine. Evolving the Spitfire - A detailed examination of the modifications (mythical and real) that turned the Mk.V into the Mk.IX":-

"When the new Spitfire version was first introduced, it kept the the original Mk.IX designation. In order to tell the difference, the crews called it 'Mk.IXB' (which later resulted in the legend that some Mk.IX had the 'B' wing, while in fact they all had the 'C' wing). To avoid confusion, the Air Ministry introduced the designation LF.IX for the 'Mk.IXB', while the original Mk.IX became the 'F.IX'. Although the 'LF' suggested a low-altitude fighter, this was not quite so, as it was actually developed to have optimum performance at 22,000ft (6,700m)."

The earliest Mk.IX were conversions from Mk.Vc airframes by both Supermarine and Rolls Royce. There were differences between those produced from each source in terms of lumps and bumps on the nose. But we won't go there tonight!
Thank you all clear the water so as clear as Mississippi muddy water 💦 😃 that was the confusing points as the letter normally (I thought) denoted the wing.
Timeline, using the official designations,

Supermarine, October 1941 first Vc, February 1942 last Vb, June 1942 first F.IX, September 1942 last Vc, November 1942 first F.VIII, February 1943 first LF.IX, May 1943 first LF.VIII, June 1943 last mark IX.
Vickers, June 1942 first Vc (1 aircraft, next 5 in August), December 1942 last Vb, February 1943 first F.IX, August 1943 first LF.IX (ignoring production of 1 in April and 1 in June) October 1943 last Vc and F.IX
Westland, first Vc April 1942, last Vb June 1942.

The RAF aircraft census starts using the Spitfire F, HF and LF designations in May 1943.

The Ministry of Aircraft Production put out monthly production reports, from March 1942 onwards at least. No doubt they do not exactly match to when the RAF made designation changes to Spitfires, but they give an idea of the timetable.

First mention of F designation, F.VB in December 1942, the last production. The F designation does not appear again until March 1943, when all Spitfires in production receive it, Vc, VII, VIII, IX and XII. In April 1943 the HF and LF designations appear. F.Vc, F.VII, HF.VII, F.VIII, LF.VIII, F.IX, LF.IX and F.XII. The F and HF VII appear in May but then become F.VII in June while April and May VII production is given as a single figure, not broken down into F and HF.

Before December 1942 the reconnaissance version Spitfires were designated P.R.U. III and IV. In December 1942 the PR designation is used, the first PR.IX were built in November 1942 but the MAP reports miss them.

Examples from other types,
In March 1942 the Beaufighters have c or f suffixes to mark numbers. The TF.X appears in December.
In March 1942 the Mosquito are F.II and T.III (in June 1942 the first mark VI is an F.VI). The mark IV becomes B.IV in September, the same month as the PR.VIII appears. In January 1943 the NF.XV and FB.VI appear while the F.II designation is still in use.

In May 1942 the Wellington Ic are split between Ic and Torpedo Ic also there are Torpedo and Leigh Light VIII. In April 1943 the GR designation is first used.

In March 1943 the Warwick I becomes the B.I.

As a warning about the limits of the reports, in October 1943 the Halifax II becomes the B.II but the mark III and V do not use the B designation.

And so on.

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