High Altitude Spitfire Mk VIII in Italy

[Spitfires Forever]

Greetings

I have a question regarding the high altitude Mk VIII's used by #'s 92 and 145 in 1943. Being a big fan of the long winged fighters I was curious about the differences between the Mk VII and the HF Mk VIII including any difference in performance. The two physical differences I have noticed is the lack of the broad chord rudder and the pipe/inlet only located on the Mk VII under the exhaust pipes. Other than that did the Mk VIII have the same high altitude equipment? I'm just curious because I am building the Mk VIII and would like to know about any important physical differences.

Cheers

[Sturmovik]

@Troy Smith may be able to help you. He's a Spitfire fan.

Edited August 26, 2022 by Sturmovik

[Giorgio N]

The Mk.VII was pressurised, the VIII wasn't. 

External features of the VII were a different canopy, with a deeper rear clear section, no entry door, different rails for the canopy, an intake on the lower port engine cowling (the pipe you have seen) and a different, shorter carburettor intake instead of the longer Aerovee.

Most VIIs had the wider rudder but the earlier type was also seen, in any case the same applies to the VIII.

The rest of the structure was the same so both variants had short ailerons, leading edge fuel tanks, retractable tailwheel and so on

[Graham Boak]

Be a bit careful about the HF designation.  As said above, the Mk.VII was pressurised, with all that implies.  However, early versions were equipped with the Merlin 61as was the F.Mk.IX (later M63) as were the F. Mk.VIII.  These aircraft were initially considered as, and used as, high altitude fighters before the HF.Mk.VII appeared, and where it wasn't used.  Most Mk.VIIs used the Merlin 64, with a modified supercharger for higher operations.  Fairly early on the Mk.VIIIs and IXs were fitted with the Merlin 66 and became LF variants, though in truth there was not a lot of difference in the optimum height.  Towards the end of production HF Mk.VIIIs and IXs appeared with the Merlin 70, again optimised for higher altitudes.  I can only find the MV-serialled Mk.VIIIs with the M70.  The HF Mk.IXs however seem to have been interspersed fairly thinnny and randomly starting early in the ML-serial range.

 

The one thing to watch about the Mk.,VIII is that the extended wingtips were only standard on early aircraft.  It is tempting to argue that these tips wee only seen on F.Mk.VIIIs with the early ruder, but this is too simplistic.   It is however a good rule of thumb - and expect to see the wide cannon bulge on these examples too.  However, the extended tips would be rarely seen on middle and late production aircraft unless specifically required.  There's no apparent link with them in aircraft with the Merlin 70.

[Spitfires Forever]

I would assume that this particular version of the Mk VIII would have the smaller lower intake and wide cannon bulges common to the early Mk VIII'S?

[Graham Boak]

 I would expect all the overseas Mk.VIIIs to have the Aerovee filter.  To be honest, I thought that every Mk.VIII had these.   The early Mk.IXs sent to Tunisia retained the small intake without a filter, but not the Mk.VIIIs.

[gingerbob]

Right, the Mk.VIII was tropicalized from the beginning.  Note also that true HF.VIIIs were for Australia, by request.

[Geoffrey Sinclair]

Mark VI, R7120 prototype taken from the production line in January 1941.   Actual mark VI production began in December 1941, finishing in November 1942, had a pressure cabin and used the extended wing.

 

The mark VII prototype AB450 was officially a conversion, coming off the production line as a Vb probably in February 1942.  Mark VII production September 1942 to May 1944.  The mark VIII being the unpressurised VII hence the extended wing tips on some VIII.  F.VIII production November 1942 to September 1943, plus 20 in November, LF.VIII production May 1943 to January 1945,  HF.VIII production May to November 1944, plus the final VIII in March 1945.  May to November mark VIII production was 359 LF and 159 HF.

 

Supermarine built F.IX June 1942 to June 1943, plus 40 LF.IX February to June 1943.  Castle Bromwich built F.IX February to October 1943, also 1 LF.IX in both April and June 1943 before starting full production in August 1943, finishing in August 1945.  HF.IX production began in March 1944 finishing in June 1945,  March 1944 to June 1945 production totals were 2,622 LF and 400 HF.IX.

[Spitfires Forever]

Did the early Mk VII's and VIII's have the larger cannon buldges?

[Graham Boak]

Yes.

[Spitfires Forever]

Thank, I cannot proceed with some confidence

Cheers

[gingerbob]

Not so sure about VII having the big bulge?

[Graham Boak]

Not guaranteed, no.  What's the serial?  That would be a rough guide.  I think that they can pretty well be guaranteed on early JFxxx, and possibly into the JGxxx range.   Like the extended wings, the big bulge lasted for quite  a long time.   But I don't think I've seen any more specific guidance - they ae rarely visible on photos.   Some of them even reached Australia - though it is possible that they were transferred from Mk.Vc stocks...

 

It might be possible to get some idea by comparing the dates on the modification number to those oi first flights, but there could be a considerable time between approval and fitting the first examples, and as I recall the Supermarine modification list had some peculiarities in such dates.

[Troy Smith]

6 hours ago, Spitfires Forever said:

Did the early Mk VII's and VIII's have the larger cannon buldges?

 

46 minutes ago, gingerbob said:

Not so sure about VII having the big bulge?

"Spitfire Mk. VII EN474 flying over the plains of Ohio in the summer of 1943. This aircraft, the 13th production high-altitude Mk. VII was supplied to USA for evaluation. In the USAAF service, the aircraft retained its British camouflage and serial, although it was later assigned the evaluation number FE-400.

An air intake for the Marshall compressor for the pressurised cockpit placed below the starboard exhausts was the characteristic feature of the type, as was the Lobelle type sliding canopy. This aricraft, however, was one of the earliest Mk. VII and featured a non-sliding pressurized hood inhereted from the earlier Spitfire Mk. VI.

This aircraft survived the war. Retired to the Smithsonian National Air & Space Museum in 1947, EN474 is today the world’s only surviving example of the pressurised high-altitude Spitfire. [USAF]"

 

[Spitfires Forever]

1 hour ago, Troy Smith said:

 

"Spitfire Mk. VII EN474 flying over the plains of Ohio in the summer of 1943. This aircraft, the 13th production high-altitude Mk. VII was supplied to USA for evaluation. In the USAAF service, the aircraft retained its British camouflage and serial, although it was later assigned the evaluation number FE-400.

An air intake for the Marshall compressor for the pressurised cockpit placed below the starboard exhausts was the characteristic feature of the type, as was the Lobelle type sliding canopy. This aricraft, however, was one of the earliest Mk. VII and featured a non-sliding pressurized hood inhereted from the earlier Spitfire Mk. VI.

This aircraft survived the war. Retired to the Smithsonian National Air & Space Museum in 1947, EN474 is today the world’s only surviving example of the pressurised high-altitude Spitfire. [USAF]"

 

If that is an early version then the large buldge C wing cover was not used from the looks of it. From what I have been able to find out the large or wide buldge cover was for use with the twin cannon set up which with the exception of a South African Squadron was not generally used in combat, although some of the first Mk Vc's to fly off the USS Ranger to Malta arrived with four cannons supposedly. Interestingly the early Mk IXc's had the wide buldge. Apparently the early Mk VIII's also carried the wide covers and who knows what blocks/serial numbers arrived with those cannon covers. Thanks for the picture, I feel relatively confident that I have the info I need for my MkVII build. My kit version of the Mk VIII with the extended wing tips and standard rudder (I previously thought all Mk VIII's had the larger rudder, appearently not) but cannot assume with absolute certainty that the covers were wide or not. I perhaps can assume that more than likely the early Mk VIII had the smaller buldges covers I think I am becoming obsessed with this topic due to AMS or advanced modellers syndrome aka OCD.

Cheers

[Spitfires Forever]

1 hour ago, Graham Boak said:

Not guaranteed, no.  What's the serial?  That would be a rough guide.  I think that they can pretty well be guaranteed on early JFxxx, and possibly into the JGxxx range.   Like the extended wings, the big bulge lasted for quite  a long time.   But I don't think I've seen any more specific guidance - they ae rarely visible on photos.   Some of them even reached Australia - though it is possible that they were transferred from Mk.Vc stocks...

 

It might be possible to get some idea by comparing the dates on the modification number to those oi first flights, but there could be a considerable time between approval and fitting the first examples, and as I recall the Supermarine modification list had some peculiarities in such dates.

The codes are both with the JF prefix. JF502 with the squadron code 4 QJ and the other markings were for JF565 with code AZ X.

[Troy Smith]

1 hour ago, Spitfires Forever said:

I perhaps can assume that more than likely the early Mk VIII had the smaller buldges covers

no. The Mk.VII , I presume because of it's untended use was not planned to have 4x20mm cannon, while the Mk.VIII, like the early Mk.Vc may well have be planned to have the option available.

Look at photos of similar airframes.

@Peter Roberts  @Magpie22  may have some info on early mk.VIII's

[gingerbob]

Indeed you are correct, Troy. And thanks for the VII info- I was on my "not-very-smart phone" earlier, so couldn't easily go digging.

[Graham Boak]

9 hours ago, Spitfires Forever said:

 I think I am becoming obsessed with this topic due to AMS or advanced modellers syndrome aka OCD.

Cheers

It is also known as "getting it right" which seems entirely commendable.

 

PS  USS Wasp, and as far as I can see all these (aboit 100) Spitfire Mk.Vc had the wide blister and all four cannon, although two of  the cannon were generally removed shortly after arrival, at least on Takali aircraft.   Finding a photo of a Mk.Vc with the narrow blister is a way of passing a dull evening.

[Spitfires Forever]

Oh yes, the Wasp. Why was I thinking Ranger? Besides, wasn't it Churchill who said something about a wasp stinging twice? I do like to get things right even though I don't post my builds and I am the only one who really knows where the warts are but it is still bothersome to see imperfections after hours of work. I try to ignore them and do better on the next build and eventually the warts turn into minor blemishes......well sort of.

Cheers