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Xiolablu3
02-12-2008, 01:54 PM
We all know that Spitfire mkV peformance changed a lot over the war years, and that thge early MkV's were very different to the later MkV versions.

However, what I wanted to know is, were the very late models of MkV in service in late'43 and early 1944 actually better performers at some heights (for example low level) than the MkIX?

I know there were dedicated so called 'FW190 killers' which were Clipped with their Superchargers cropped for all out low level performance. Were these later planes better performers at low level than some versions of the MkIX Spitfire?

Or was most mkIX production LF models anyway, which were better performers than the MkV LF high boost models?

Basically, how does the 1943 LF mkV Spitfire compare at low level to the various MkIX marks of Spitfire in late 1943?

Kurfurst__
02-12-2008, 02:10 PM
The clipped, cropped LF Mk V was a sucker, basically... so impressive numbers for a couple hundred feet altitude, then it falls off BAD.

I think the FW 190s 'killers' were the Mk XIIs with their low alt Griffons, but the Mk VLF... naaaah. The thing was slower than the FW 190A at any altitude. 10-20 km/h at low altitude... as much as 120 km/h at 6000m/20k feet.

Recycled old airframes iinto low altitude fighter/bombers and strafers, to make some extra use of them, that what the Mk VLF really was. If you plot its performance curves vs altitude and put some others next to it, you will see immidiately for yourself. Its a bit better than the Merlin 61 Spits for really low altitudes, but no alternative imho for a Merlin 66 IXs. Probably pretty good turner for tree-top dogfights though, all that extra power going into such a light airframe...

gdfo
02-12-2008, 03:07 PM
xiol,

do you mean in WW2 or in IL-2?

thefruitbat
02-12-2008, 03:16 PM
Kurfurst's right i think, it was the griffon engined MkXII that you are thinking of. I think this was essentially a MkV airframe, c wing armenant, with clipped wings with a griffon stuck in. It Entered service Feb 43 with No 41 squadron, and was used as a low level interceptor. This was replaced with the interim Mk XIV in spring 44, until the definitive Mk21.

cheers fruitbat

Xiolablu3
02-12-2008, 03:41 PM
Originally posted by gdfo:
xiol,

do you mean in WW2 or in IL-2?

IRL in WW2 mate http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

hop2002
02-12-2008, 04:53 PM
The V LF would be slower than a 190 at any altitude, but would have a higher climb rate below 10,000 ft, and a large power to weight advantage at lower altitudes.

If you look at the performance figures for the LF Vb and LF IX, you'll see that at low altitudes (below say 5,000 ft) the Spitfire LF V performs about the same as the LF IX. The reason is the LF V was tuned to give best performance at about 5 - 6,000 ft, the LF IX gave best performance at 18 - 20,000 ft.


Or was most mkIX production LF models anyway, which were better performers than the MkV LF high boost models?


From memory, about 4,000 LF IX, 1,300 or so F IX, a few hundred HF IX. The figures are very rough, though.

biggs222
02-12-2008, 05:03 PM
Originally posted by thefruitbat:
Kurfurst's right i think, it was the griffon engined MkXII that you are thinking of. I think this was essentially a MkV airframe, c wing armenant, with clipped wings with a griffon stuck in. It Entered service Feb 43 with No 41 squadron, and was used as a low level interceptor. This was replaced with the interim Mk XIV in spring 44, until the definitive Mk21.

cheers fruitbat

actually it was the airframe of the mkVII, except without the high altitude wing tips (pointy buggers). the mkVII airframe was the first to incorporate the larger area pointed rudder (and im not talking about the bigger mkXIV rudder) as well as a retractable tailwheel.

It was the mkIXs that used the mkV airframe, with modified radiators and slightly later the bigger carburetor. also the elevators where changed in what seems the later mkV variant airframes of which were used for making mkIXs, where the outter end of the elevator now wraps around the tip of "wing" as it were... I dont know what its offically called but just take a look at il2/AEP/1946 for reference (mkV v.s mkIX elevators)

Ratsack
02-12-2008, 05:06 PM
Xio,

Spit Vb with Merlin 50M, standard wings, tested at Boscombe Down in early 1943:

Alt--------Speed-------Rate of Climb
2,000 ft - 333.5 mph - 4,720 fpm
5,900 ft - 350.5 mph - -
8,000 ft - 348.5 mph - 4,100 fpm
12,000 ft - 345.5 mph - 3,500 fpm
18,000 ft - 339.5 mph - 2,610 fpm
24,000 ft - 327.5 mph - 1,740 fpm


This is faster than the old-style Spit IX (Merlin 61) tested by the AFDU in April 1942, up to 8,000 feet. Relevant data below:

Alt--------Speed
4,000 ft - 326 mph
8,000 ft - 344 mph
12,000 ft - 363 mph
and so on.

I don't have data for a standard 18lb boost LFIX, but the 25lb boost version is faster than the LFVb at all heights.

In contrast, the first production Spit Vb:

Alt----------Speed----Rate of Climb
2,000 ft- - - - - - - 3,240 fpm
5,000 ft - - - - - - -3,240 fpm
10,000 ft - 331 mph - 3,250 fpm
15,000 ft - 351 mph - 3,250 fpm
20,000 ft - 371 mph - 2,440 fpm

and so on.


So, Kurf is overstating the case to say the Spit LFV sucked. It was very fast below 5,000 feet, with an excellent rate of climb. It's performance was good to 10,000 feet, not the first few hundred.

Above that, not so flash.

cheers,
Ratsack

thefruitbat
02-12-2008, 05:09 PM
Ratsack, have you got anything on the spit MkXII details to compare, out of interest?

fruitbat

Ratsack
02-12-2008, 05:19 PM
The prototype MkXII, DP 845, with standard wings and fixed tail wheel, but otherwise at MkXII standard:

Alt ---------Speed ----Rate of Climb
2,000 feet - 355 mph - 3,760 fpm
5,700 feet - 372 mph - ------
8,000 feet - 372 mph - 3,130 fpm
14,000 feet - 379.5 mph - 2,760 fpm
17,800 feet - 397 mph - --------
24,000 feet - 392 mph 1,780 fpm

Geofrey Quill recalls this plane winning a specially staged race between the captured Fw 190 A-3, a Typhoon and 'a Spitfire'. The object of the demonstration was to show some high-powered dignitaries the superiority of the Focke-Wulf, and Supermarine Vickers were instructed to provide a Spitfire. However, a type wasn't specified, so Quill selected his baby, DP 845, and quite stuffed the demonstration.

cheers,
Ratsack

thefruitbat
02-12-2008, 05:28 PM
Geofrey Quill recalls this plane winning a specially staged race between the captured Fw 190 A-3, a Typhoon and 'a Spitfire'. The object of the demonstration was to show some high-powered dignitaries the superiority of the Focke-Wulf, and Supermarine Vickers were instructed to provide a Spitfire. However, a type wasn't specified, so Quill selected his baby, DP 845, and quite stuffed the demonstration.

cheers,
Ratsack

I like this Geofrey Quill bloke!!

cheers for the info, makes me wonder why more effort wasn't put into Griffon engined spits?

fruitbat

horseback
02-13-2008, 12:51 AM
A correction about the Mk XII; it was made from MkVIII/IX airframes, with a 'c' wing. The photos all show the larger pointed rudder, and that some had a retractable tailwheel and some had a fixed tailwheel, which was the main identifier between the VIII and the late IX.

As for the 'later' Mk Vs, since the Mk V production ended once Fighter Command realized that the Mk IX experiment worked, some of those Mk V airframes that were still usable got the the shorter wings and had their superchargers cropped to maximize their low-level performance.

Unfortunately, since these airframes were usually pretty much used up by that time (i.e., "clapped out"), they were often referred to as 'clipped, cropped and clapped.'

They were, however, a good deal more competitive with the 190 than the earlier MK Vs, especially given the differences in pilot training & experience at the point in the war that they were introduced.

cheers

horseback

Kurfurst__
02-13-2008, 03:44 AM
Half of the Mk XII (a nice round number, 100 were produced) were made from Mk V, the other half from Mk VIII airframes, so you are both correct...

JG53Frankyboy
02-13-2008, 03:50 AM
Originally posted by Ratsack:

Spit Vb with Merlin 50M, standard wings, tested at Boscombe Down in early 1943:

Alt--------Speed-------Rate of Climb
2,000 ft - 333.5 mph - 4,720 fpm
5,900 ft - 350.5 mph - -
8,000 ft - 348.5 mph - 4,100 fpm
12,000 ft - 345.5 mph - 3,500 fpm
18,000 ft - 339.5 mph - 2,610 fpm
24,000 ft - 327.5 mph - 1,740 fpm


This is faster than the old-style Spit IX (Merlin 61) tested by the AFDU in April 1942, up to 8,000 feet. Relevant data below:

Alt--------Speed
4,000 ft - 326 mph
8,000 ft - 344 mph
12,000 ft - 363 mph
and so on.

I don't have data for a standard 18lb boost LFIX, but the 25lb boost version is faster than the LFVb at all heights.

...........................

the 18lb boost LF.Mk.IX too

http://www.spitfireperformance.com/bs543.html

Ratsack
02-13-2008, 06:34 AM
Originally posted by horseback:
A correction about the Mk XII; it was made from MkVIII/IX airframes, with a 'c' wing. ...

I should've been more specific. What I meant by 'standard wing' was 'full-span wing', as opposed to the clipped variety. All of the 100 Spit XIIs were clipped, except for the very first production example. The prototype (which was also one of the prototypes for the MkVIII and then for the Mk20) had the full-span wings during these speed runs.

cheers,
Ratsack

Xiolablu3
02-13-2008, 07:02 AM
Originally posted by thefruitbat:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">

Geofrey Quill recalls this plane winning a specially staged race between the captured Fw 190 A-3, a Typhoon and 'a Spitfire'. The object of the demonstration was to show some high-powered dignitaries the superiority of the Focke-Wulf, and Supermarine Vickers were instructed to provide a Spitfire. However, a type wasn't specified, so Quill selected his baby, DP 845, and quite stuffed the demonstration.

cheers,
Ratsack

I like this Geofrey Quill bloke!!

cheers for the info, makes me wonder why more effort wasn't put into Griffon engined spits?

fruitbat </div></BLOCKQUOTE>

I have also often wondered this.

Geoffry Quill suggested that it was because Rolls Royce had put so much effort into the Merlin, that they didnt want all their work made redundant right away, and so dragged their heals over Griffon production.

Other sources state manufactoring difficulties.

Other sources state that they had the number of XIV's they wanted in late 1944-45, just over 100 flying daily in France, and just replaced losses. To put this into perspective, the Luftwaffe defended the whole French coast in 1942 with 130 aircraft.

By this time Luftwaffe aircraft (in the air) were hard to find, so maybe they relaxed a bit. Most Spitfires were being pressed into ground attack at this time, because of the lack of enemy air opposition.

The German phrase from this time is

'Wo ist der Luftwaffe?' (Where is the Luftwaffe)

This shows the incredible amount of losses being incurred by the LW at this time, as 1800 FW190D's and about the same number of 109K's were produced between the end of 1944 and the end of the war. To lose nearly 4000 planes of just these two types in 4 months just whos the pressure they must have been under. I guess most must surely have been destroyed on the ground and never flew.

For interest, heres the part where Quill messed up the 'race' :-

http://www.crew-green.com/Griffon%20Spitfire.htm

The part he doesnt mention is that RAF pilots were having to face the FW190 at this time with inadequate Spitfire V's, and not the Griffon engined Spit, so he was possibly doing his fellow RAF men a disservice here. WHat was needed was a demonstration that the MkV was not good enough, not that all was well. I think Ego got in the way of the big picture a bit here. Still an entertaining read tho.

Thanks for all your comments http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Kurfurst__
02-13-2008, 07:22 AM
Originally posted by Xiolablu3:
This shows the incredible amount of losses being incurred by the LW at this time, as 1800 FW190D's and about the same number of 109K's were produced between the end of 1944 and the end of the war. To lose nearly 4000 planes of just these two types in 4 months just whos the pressure they must have been under. I guess most must surely have been destroyed on the ground and never flew.

That`s some very silly logic; by the same flawed approach, the USAAF must have lost something like 250 000 fighters during the war. Ie. they produced about 300 000, and how many were around with units at the end of the war, 10-20-30 thousend...?

It`s just not that simple.

As for how can five or so Spitfire XIV Squadrons put up a hundred aircraft in the air at a time, when they might have, at a very theretical full established strenght, if all are servicable about a hundred (ie. 5x20), but with only 12-13 of those flying operational sorties, the rest being reserve aircraft... that`s very resourceful as well.

I doubt the greatest number of Spit XIVs up in the air at a time was ever more than 40-50 during the war.

leitmotiv
02-13-2008, 08:25 AM
Read this, then post:

http://www.aviationbookcentre.com/__12_product_info3_as...4-71FB36A21CCC9.html (http://www.aviationbookcentre.com/__12_product_info3_asp3_5_prdID4_55587_prdName59_T he_Story_of_the_Spitfire_An_Operational_and_Combat _History5_usrID36_59DAB3FF-AB73-4A2A-A004-71FB36A21CCC9.html)

Ratsack
02-14-2008, 05:45 AM
Originally posted by Xiolablu3:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by thefruitbat:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">

Geofrey Quill recalls this plane winning a specially staged race between the captured Fw 190 A-3, a Typhoon and 'a Spitfire'. The object of the demonstration was to show some high-powered dignitaries the superiority of the Focke-Wulf, and Supermarine Vickers were instructed to provide a Spitfire. However, a type wasn't specified, so Quill selected his baby, DP 845, and quite stuffed the demonstration.

cheers,
Ratsack

I like this Geofrey Quill bloke!!

cheers for the info, makes me wonder why more effort wasn't put into Griffon engined spits?

fruitbat </div></BLOCKQUOTE>

I have also often wondered this.
... </div></BLOCKQUOTE>

Long post warning.

Secondly, I'm going from memory of some research I did a long time ago, so details may be wrong, but the gist should be roughly in the ball park.

It was a question of priorities. The first thing to understand is that the key decisions were made in 1940 while the Battle of Britain was at its peak. At this time the Brits reasonable inferred that the Germans would try to finish Britain off in spring 1941. This would entail a reprise of the daylight phase of the BoB. In light of their recent experience which showed them that their numbers were inadequate to meet such a threat, the emphasis was on numbers of fighters for 1941.

The next item in the order of importance was cannon armament. The Brits had lots of evidence that their 0.303 machine guns were at or near the end of their effectiveness. Examining the hundreds of German wrecks littering the English countryside, they found that in very few cases had structural damage been done to the airframe by the 0.303s, but that most of the Luftwaffe planes had fallen victim to hits on critical parts of the plane: controls, radiators, engines, fuel tanks or aircrew. It therefore followed that if the Germans added a modicum of light armour to critical parts of their bombers, the 0.303 would be rendered almost completely ineffective. In contrast, they had plenty of evidence of the effectiveness of the 20 mm cannon on the German fighters, underlined by the experience of the one squadron that flew the Spit MkIB for a short period in August 1940. Cannon were therefore high on the list of priorities for fighters in 1941.

Best possible overall performance came third. This order of priorities makes sense when you consider the British strategic position in late 1940.

What it meant in terms of plans for fighter production was, firstly, that they needed to keep the Hurricane vaguely competitive until summer 1941. That meant the Hurribus got priority on the two-speed Merlins (i.e., the Hurricane MkII that went into production in mid 1940). This had the added advantage of keeping Hawker going in anticipation of the next generation of fighters.

For the Spitfire, these priorities meant going for incremental changes that produced the MkVb. The more powerful engine got the top speed up to 370-75 mph at 20,000 ft, improved the rate of climb to 3,250 fpm, and the b' wing gave it the cannon so desperately needed. It was an improvement over the MkI, but was not a significant re-design. It was just the interim type. This is where the story gets weird to the modern eye.

In retrospect, the primacy of the Spitfire in the RAF of WWII looks inevitable. But it wasn't. In fact, Supermarine were not well-liked in the Air Ministry. It wasn't a personal tiff ala Milch vs Messerschmitt, but a question of Supermarine being very slow at delivering what they promised. This was noted before the prototype Spitfire flew, and was underlined when the deliveries of the production MkIs were much slower than anticipated. It was with palpable relief that the Morris factory at Castle Bromwich got up and running in mid 1940, producing the Spitfire MkIIa. CB subsequently produced the vast bulk of Spits made.

In contrast, Hawker enjoyed an excellent reputation in the Ministry and RAF. They had long experience of fighters again in contrast to Supermarine, whose specialty was flying boats and they also had long experience with big production runs. They also had an excellent designer in Camm.

With that background, it's not surprising that the Ministry and RAF thought it highly desirable that the next generation of fighters come from the Hawker stable. Here they were thinking about the Typhoon / Tornado fighter. The Spitfire V was the interim type to tide the RAF over the danger period of 1941, to be joined over that period by the Typhoon or Tornado, which would eventually replace it in the main day fighter role. It was anticipated that this would happen in 1942. After that, the Spitfire would be used primarily in the high-altitude role, where it was already acknowledged that the Hawker fighter would be inferior.

This might look strange to our eyes, but if we look at the on-paper performance of the Typhoon, it sounds a lot more sensible. The beast would have a top speed of 405 mph at 18-20,000 feet. It would carry 4 x 20 mm cannon, or 12 x 0.303s (with a strong preference for the former). It would have a bubble canopy. It would have provision for heavy underwing stores. We might be talking about the Fw 190 A. Of course, the Typhoon didn't turn out like the Focke-Wulf, but that was still in the future, as were the chronic problems with the Napier Sabre.

The plan for the later Spitfires was that they would use the advanced Merlins (i.e., the two-speed, two-stage Merlins subsequently fitted to the MkVII, VIII, IX, and XVI), and thus enjoy excellent high altitude performance. These advanced Spits would be the MkVII, and the MkVIII as the back-up, all-purpose version. The MkVI was the interim high altitude type.

By this stage Vickers Supermarine and Rolls Royce had begun work on the Griffon powered Spitfire, but this work was initially discouraged by the Ministry. This seemingly odd attitude makes more sense when you consider that Rolls Royce had responsibility for developing the Merlin, which was the power plant for the current crop of fighters, and the power plant for the next generation of high altitude fighters, and the power plant for some planned bombers, and the power plant for the back up versions of a couple of heavy bombers should the Vulture go t*i*t*s up. Westland wanted the Merlin for the Whirlwind, too, but were forced to make do with the Peregrine. The Ministry just wanted RR to concentrate on the job in hand, and not worry about advanced ventures for a type that they hoped to phase out anyway.

All of this did indeed go t*i*t*s up in early 1942, with the mature Fw 190 A-3 proving to be the best fighter in the world, and the Typhoon failing. But by then the plans were set. All that could be done without drastically cutting production either for the bombers or fighters, was to fast-track the 60-series Merlins at the expense of the Griffons, while still maintaining a huge flow of power-egg engines to create the enormous heavy bomber fleet the RAF was building. I suspect that they were half hoping that by the time they had to make a decision about the Griffon Spitfire, the Super Typhoon (i.e., Tempest) would be on hand and they could go with that instead.


cheers,
Ratsack

Richardsen
02-14-2008, 07:18 PM
The latest LV V's where out-flying the XIV. Those had four blade prop and a Merlin m55 engine. they had the same hp number at low level as the LF IX, but was less draggier and alot lighter. They where stunning down low, but useless above 10000ft.

Ratsack
02-14-2008, 09:29 PM
Originally posted by Richardsen:
The latest LV V's where out-flying the XIV.

I am skeptical of that. Do you have figures for such a MkV, or a similarly equipped Seafire?

cheers,
Ratsack

Richardsen
02-15-2008, 10:31 AM
Originally posted by Ratsack:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Richardsen:
The latest LV V's where out-flying the XIV.

I am skeptical of that. Do you have figures for such a MkV, or a similarly equipped Seafire?

cheers,


Ratsack </div></BLOCKQUOTE>

I don't have enough evidence to prove that.
I've just read some pilot quotes.. One quote says something like: They did outrun us over short distances and they had a superb rate of climb.