1939-early 1940 (not forgetting that the Spitfire didn't see intensive combat, particularly against fighters, until May 1940): Constant-speed propellers (priority for C/S props was given to bombers). Better protection for fuel tanks; in the interim, this would have to be the linatex that was adopted during the B of B; at the time, self-sealing tanks would have reduced the fuel capacity. Earlier adoption of pilot armour (the Hurricane was being fitted with armour in late 1939) and better blown canopy that could be jettisoned.
Improvements to the Spitfire
1939-early 1940 (not forgetting that the Spitfire didn't see intensive combat, particularly against fighters, until May 1940): Constant-speed propellers (priority for C/S props was given to bombers). Better protection for fuel tanks; in the interim, this would have to be the linatex that was adopted during the B of B; at the time, self-sealing tanks would have reduced the fuel capacity. Earlier adoption of pilot armour (the Hurricane was being fitted with armour in late 1939) and better blown canopy that could be jettisoned.
Clayton Magnet
Staff Sergeant
- 914
- Feb 16, 2013
So, please pardon my ignorance. What were the specs and possible timelines for the Mk.III? It must have been superior to the Mk.V if it is claimed to have been a good possible match for the Fw 190A's. Was it seriously only ignored to build more Mk.II Hurricanes? Please enlighten me
The Mk III was abandoned in favour of the Mk V which was a much simpler job to do. Essentially bolting a modified Merlin XX onto a Spitfire I air frame was seen as more expedient, and the Mk V was a successful aircraft.
The Mk III was far from perfect, there were problems with cooling and chopping three and a half feet of each wing, reducing wing area to 22o sq. ft. had an adverse effect on handling. Boscombe Down noted that 'turning performance at heights from 20,000 to 35,000 feet show rapid deterioration in manoeuvrability'.
Dowding didn't like the clipped wings either, fearing it made the Spitfire resemble he Bf 109 more strongly, 'a matter in which mistakes have already been made'. He asked for 'a pair of ordinary wings' to be fitted to the prototype. He was also concerned about the 'dangerously long' landing run of the new version.
As ever, tinkering with a successful design is never as easy in practice as it is in theory!
Cheers
Steve
The Mk III was far from perfect, there were problems with cooling and chopping three and a half feet of each wing, reducing wing area to 22o sq. ft. had an adverse effect on handling. Boscombe Down noted that 'turning performance at heights from 20,000 to 35,000 feet show rapid deterioration in manoeuvrability'.
Dowding didn't like the clipped wings either, fearing it made the Spitfire resemble he Bf 109 more strongly, 'a matter in which mistakes have already been made'. He asked for 'a pair of ordinary wings' to be fitted to the prototype. He was also concerned about the 'dangerously long' landing run of the new version.
As ever, tinkering with a successful design is never as easy in practice as it is in theory!
Cheers
Steve
Bad luck too, the first prototype wings (from memory) were destroyed in a bombing raid. But it was shortsighted in that the 109 was seen as the only German fighter to compete against and they were in the 'altitude race' of the time, yet they did have enough intelligence to know something else was coming along. Moever as the RAF moved onto the offensive it did not take a lot of thought to realise that the fighing would move to where the bombers were (around 15,000ft at the time).
it was a bad allocation of Merlin XXs to put them in Hurricanes.
Part of the problem was that there was no clear stategic plan, direction or foresight. Leigh Mallory's 'leaning yowards the enemy'was an expensive disaster, especially when the need for Spits was in Malta and North Africa that was where the real battles were.
So the Spit V matching the 109F seemed 'right' to them, they thought they'd just fight the BoB again over France and the Luftwaffe would fly up to get hammered. It didn't happen and it was Fighter Command that got hammered.
If the Merlin 60 series had not been available...... Rolls Royce pulling the RAF's chestnuts out of the fire again. Naturally it was RR that fitted the first trial 60 series in a Spit on their own intiative (Hives had little patience with MAP and the rest).
The other problem that a LR Spit was killed by Portal so they had no way to actually fight over Europe as they didn't have the range.
They should have put heaps into Malta and NA far earlier, where they could fight the Luftwaffe and damage it amd make a strategic difference. Instead they left it to Hurricanes and P-40s and the pilots they suffered accordingly as did the people and troops on the ground.
The Mk III also should have gone ahead (wth std wings) even if just because it had far more scope for development with better Merlin XX series engines known to be coming along (remember the 60 series was barely a concept back then in late 40 and early 41). On the same engine power it was at least 10mph faster, maybe as much as 20mph and a far wider fighting altitude range.
41 and 42 was when Fighter Command was stuffing up by the numbers and it is hard to pick anything they did right.
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- Thread starter
- #25
The Spitfire V was a combination of Spitfire I airframe and Merlin 45 engine (single-speed supercharger), not Merlin XX (2-speed S/C). There was really no reason not to go with 'full size' wings on the Spit III if that decision is made.
The Spit V served with distinction, still it was a mistake not going on with the Mk.III that offered not just a better performance, more internal fuel, but also 6 months earlier service date. There is also no reason not to install Merlin 45 when it becomes available, if the Merlin XX is deemed as a too neccesarry for the needs of Bomber Command
400 mph was claimed (unarmed?). The 1st prototype was ready for weighing on 14th March 1940.
Merlin XX was the best engine in the world for high altitudes when introduced (mid 1940), it gave another ~15 mph to the 8-gun Hurricane, thus cutting considerably the performance deficit vs. the Bf 109E.
The Spit V served with distinction, still it was a mistake not going on with the Mk.III that offered not just a better performance, more internal fuel, but also 6 months earlier service date. There is also no reason not to install Merlin 45 when it becomes available, if the Merlin XX is deemed as a too neccesarry for the needs of Bomber Command
400 mph was claimed (unarmed?). The 1st prototype was ready for weighing on 14th March 1940.
Merlin XX was the best engine in the world for high altitudes when introduced (mid 1940), it gave another ~15 mph to the 8-gun Hurricane, thus cutting considerably the performance deficit vs. the Bf 109E.
That was not the case using the Merlin XX. The Spit III prototype ended being use as as an experimental and development aircraft, to try out all sort of stuff. It was the first airframe fitted with a Merlin 60 and that had (as you would expect) cooling issues, still 420mph out of the box though....
The best solution, as was done in the end, was the standard wing and just clip (or extend) as required.
bobbysocks
Chief Master Sergeant
welcome to the forum lisa....you seem to have a wealth of knowledge...
Ignoring the dubious source (no doubt used as an attempt to discredit the Spitfire by its No. 1 hater), the attached RAE notes show how different design features affected the top speeds of Merlin powered Spitfires; an "ideal" Spitfire IX, for example, could have reached 445 mph (table 3).
Can't access it for some reason.
I was having the same problem; clear your cache by holding down the control key and hitting F5.
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Thanks for the compliment. But been here before under a dfferent name some years back.
Clayton Magnet
Staff Sergeant
- 914
- Feb 16, 2013
So the RAF possibly had an aircraft with Mk.IX -ish performance in the pipeline for late 1940? Seems like it would have been a world beater.
parsifal
Colonel
I could see it, but sorry wont read it. lets just say I have issues with its owner
GregP
Major
Hi Parsifal,
Could you clarify that just a wee bit? In a post or maybe in a PM? Just curious, not wanting to jump in anywhere and not saying anything at all.
Could you clarify that just a wee bit? In a post or maybe in a PM? Just curious, not wanting to jump in anywhere and not saying anything at all.
- Thread starter
- #35
It certainly would.
The cooling problems were mentioned in a Boscombe Down report for N3297 of February 1941. It had the modified Merlin XX fitted at that time. The Mk III prototype was sent back to Supermarine on 3rd March and thence to Rolls Royce, Hucknall, for installation of the Merlin 60 and 61, becoming the F Mk IX prototype.
It might be argued that the Mk III was a missed opportunity, but the decision to cancel it in lieu of the Mk V was taken promptly and decisively at a meeting of the Joint Development and Production Committee as early as March 1941. It's impossible to argue that the Mk V wasn't a successful aircraft in its own right. Given the need for war time expediency, Spitfires were needed yesterday, not in a few months time, the correct decision was made. It was the sort of decisive decision making that was so often lacking in RLM/Luftwaffe programmes.
I would have liked to see the Mk III developed, it might have become my favourite Spitfire over the Mk I, but it was more important to get a competitive aircraft to squadrons with minimal disruption to production.
Cheers
Steve
fastmongrel
1st Sergeant
Didnt a lot of the improvements in the MkIII end up in the MkVIII so in a way the MkIII did get into production.
- Thread starter
- #38
Since the Mk V was a later aircraft than the Mk III, I'm not sure that waiting for another 9-10 months to have a 370 mph aircraft vs, having a 390+ mph aircraft right now was that a great thing. Majority of RAF Spitfires in 1941 was still comprised of 360 mph Spitfire I and II, and UK was outproducing Germany and Italy in fighters, combined.
We can recall that aircraft were still flown by pilots, and, since those don't grow at trees, why should they fly a less performing fighter, in a later date.
We can recall that aircraft were still flown by pilots, and, since those don't grow at trees, why should they fly a less performing fighter, in a later date.
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Not disagreeing with the need for the Spit V to 'fill in', but it was shortsighted not to continue and then later introduce the III, if they had done that then it should have come on line about the same time as the 190, which it would have been a very close match to it with a Merlin XX series and markedly superior with a later Merlin 60 series. The main thing was it cleaned up a lot of issues with the Spit in terms of parasitic drag, meaning better performance with less power. The Merin XX had a lot of development potential (at the end 25lb boost) and could have kept the III competitive with the 190A's development as well as the early (at least) 109Gs.
This demand for the Merlin 60 series for Spits, to be competitive, rippled right through the system and held up the Mosquito getting them.
But they were fixated on the 109 and the altitude war of the time and for that the V was fine, but it was a one trick pony.
N3053 was at Boscombe Down, fitted with a Merlin XX, on 13th February 1941. It must have been there at the same time as N3297 (the Mk III prototype) so it is difficult to argue that the Mk V was a later aircraft. The Mk III was cancelled in favour of the Mk V on 6th March 1941.
The Mk V was officially revealed in May 1941 and by the summer of 1941 Nos. 41, 54, 64, 91 and 92 Squadrons were all flying Mk V conversions. Supermarine could not have delivered the Mk III in this time frame and that is the essence of why the decision was taken to abandon it in favour of the Mk V. Fighter Command needed an aircraft capable of competing with the Bf 109 F at this time not months later.
Cheers
Steve
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