Spitfire development, why did Merlins last so long?

[At Sea]

I was wondering if anyone knew why the Merlin powered Spitfires remained in production for so long, up to 1944 this may have made sense but they were still being delivered new post war.

I know the Griffon has its problems but given the success of the XIV and XIX, not to mention Typhoons etc surely the IX / XVI series had had their day?

[Work In Progress]

Possibly because it was as much aeroplane as was needed, and there was a lot o infrastructure in place to support them in terms of know-how and spares and supply chain. The VIII, IX and XVI remained pretty competitive against most things they faced right up to the end of the war, and for some missions were better than the Griffon Spitfire. In particular the Merlin was a lot less of a gas guzzler, so could handle longer ranges and patrol endurances. Depending on what you were expecting to fight, you might not need the additional top speed or rate of climb of the Griffon Spitfire.

Edited March 11, 2013 by Work In Progress

[The wooksta V2.0]

There's also system inertia to take into consideration. They set up this huge system to mass produce engines and airframes - both here and in the US - which took some time to get into gear. Slowing it all down to switch to newer engines/airframes isn't easy.

Plus there's also the issue of keeping a labour force together - Bristol had to produce a minimum number of useless Buckinghams before they could switch to Brigands because if they'd simply cancelled them, the workers would have gone elsewhere and they couldn't build the Brigand.

[gingerbob]

Well, the VIII and PR.XI were pretty much done in Jan '45. Castle Brom delivered XVIs into August (with a couple of leftovers in Sept), which is probably the inertia referred to above- they'd have wanted to keep the machine spooled up until the European war was over- plus they were still getting really established on the Mk.22. (The IX ceased a month sooner, and was in smaller quantities at the end.) What's really interesting is that the Seafire III was also in production until about June/July '45!

So, not much to speak of after war's end, and Castle Brom was supplying a commitment to Russia, who got a large proportion of IXs for the last year or so, and the XVI for 2TAF. As Work in Progress said, it was enough to get the job done.

bob

[Jennings Heilig]

Not to mention the fact that it was just simply a superb piece of engineering. It just plain worked, and worked well.

[Edgar]

The main answer is that there were customers for them; check on the number of countries that bought them post-war, and you might get a surprise. Just before the war ended Middle East Command were told to sort through their stock of airframes, in order to find those most suitable for onward sales.

Also, you're labouring under a slight misapprehension, since the last VIII was delivered in January 1945, the last IX was in June 1945, and the last XVI was August 1945, so they didn't last long after the war. Many went into M.U.s, and simply waited for customers.

The XVI carried on longest probably because of the surplus of Packard Merlins for which a home needed to be found.

The last (partial) airframes, built by Castle Bromwich, were for Griffon-powered 22s, and the last one test-flown from the airfield was in January 1946.

Edgar

[At Sea]

The above comments all make it clear;

Fuel economy & mission suitability.

I did not realise production stopped in '45. I guess that if you havd aircraft you may as well take them on charge weather they have a Merlin or not.

I agree that the merlin IX and it's derivatives as well as the VIII were probably much nicer to fly than the more brutal Griffon engined aircraft.

[Seahawk]

What's really interesting is that the Seafire III was also in production until about June/July '45!

Not quite so surprising when you consider customer reaction to the Seafire XV. I'm quoting from memory here but Mike Crosley was on one of the first British Pacific Fleet squadrons to convert to the Seafire XV. IIRC they regarded it as a deathtrap and, had they been required to do another tour over Japan (VJ-Day intervened), would have pleaded to retain their Seafire IIIs. They Gave Me A Seafire will give you chapter and verse.

[Test Graham]

Whereas all the reasons given above are good, there remains the point only touched on in the last posting: what else could have been built instead of them? There was no great pool of alternatives. RR were already building Griffons as fast as they could. Remember that many of the Merlins were being built by Ford, on true mass-production tooling that took years to set up and would have taken more years to tear down and replace. Further, there was still development life in the Merlin - the 100 series were more powerful still, and the combination of aft tanks and big tail would have solved the one remaining serious fault of short range.

[gingerbob]

Graham, Ford's Merlins were (unless I'm mistaken) of the Merlin XX generation- 2-speed, but single stage, primarily for Lancs and, I imagine, still Mossies, too. RR's factories were more responsive. But the Merlin was pretty well done by 1945, in terms of Spitfire development- in each case the decision went in favor of the Griffon.

My comment about the Seafire III, Seahawk, was more that this was essentially still a Spit V airframe being built at (or almost) the end of the war- that strikes me as somewhat remarkable. Your point (and Graham's) is good, though- delays of subsequent development, and therefore production, resulted in even more of the same. The fact that "the same" turned out to be quite adequate for the task at hand (mostly) certainly helped.

bob

[Test Graham]

Ford was certainly set up for the Merlin XX series engines, and these were still in use in 1944-45 but not in the same quantities as before. Many Mosquitos had gone over to two-stage engines, the Hurricane line had (finally!) closed, and Merlin Halifaxes were fading. I don't know how Ford adjusted to this, but production of at least significant parts of the 60-series seems likelier than partial abandonment and early conversion to civilian use. Or was the factory simply abandoned postwar? Less is made of the run-down of the shadow factories than of their build, understandably.

Like the Hurricane, one reason for the continuation of Merlin Spitfire line was in the final contribution to the long-promised number of fighters to the USSR. Also like the Hurricane, diversion from pure fighters to fighter-bombers meant that cutting-edge performance in air superiority was not actually necessary. The loss rates of fighter-bombers suggests that the reduced production caused by closing down the production line for a change-over would not have been acceptable, or at least not desired.

So there's a whole range of reasons. Perhaps what should be remembered is that in wartime production is a good (or even a god) in itself, and is not going to be stopped without very good reason. The key reason for keeping the lines going is that there was no undeniable requirement for change.

[Seahawk]

My comment about the Seafire III, Seahawk, was more that this was essentially still a Spit V airframe being built at (or almost) the end of the war- that strikes me as somewhat remarkable.

I see your point. And agree.

[gingerbob]

Graham, I shouldn't have said RR was "more responsive". Rather, "more flexible"? The whole point of Ford was to churn out Merlins, and the Merlin XX (and derivatives) was the production standard Merlin type from early '41. I believe they remained on this generation to the end- March '46 or so. (Here's a blurb that talks about it a bit.) My point was that they were still supplying Lancs, and probably SOME Mossies (FB.VIs? also perhaps a small number of T.IIIs?- I don't know the details of Mossie production offhand.) Incidentally, Castle Brom was also building Lancs, in relatively small numbers, to the end.

The whole question of 1-stage vs 2-stage was a bit tricky, as an old book I've only just discovered goes into- more to come privately. Packard in the US did change over, at least in part, to 2-stage. At one time it was desired that they'd switch completely, but I'm not sure if they ended up doing so. (That factory WAS abandoned- I recently found an interesting website that talked about it.) But the airframe plan had to be coordinated with the engine plan, and/or vice versa.

Castle Brom was intended to switch to the Spit 22, and the IX was not intended to remain in production as long as it did. But the whole 20-series programme was long-delayed (which is one reason we have the 14 and 18). Perhaps more radical steps would have been taken (the whip cracked more viciously?) had the Spit IX not been good enough for the immediate need. The supply to Russia is a valid point, too, though I'd have to look at my sources again to see how that was viewed in connection to Spit IX production.

bob

[At Sea]

This is what I like about this place, ask a fairly simple question (though nothing Spitfire related seems to be simple!) and get some very thorough answers.

Nice to learn something every time I log on.

Thanks everyone! :-)

[Edgar]

In 1944 Russia "requested" 1200 Spitfires and the same number of Mosquitos, but there was growing resistance to doing too much for a country which was seen as "all take, and no give." This could have been another reason for continuing with the IX, just to keep them quiet, while we continued with the Griffon; I would put nothing past the Machiavellian minds of officialdom.

Edgar

[Work In Progress]

I knew they'd had quite a lot of Spitfires but I hadn't heard about the request for Mosquitos. Did they get any? I don't think I have ever seen reference to them.

[Seahawk]

I knew they'd had quite a lot of Spitfires but I hadn't heard about the request for Mosquitos. Did they get any? I don't think I have ever seen reference to them.

Yes, they got one for evaluation, a used Mosquito B.IV DK296 ex GB-G of 105 Sq. Think the Americans, who were unhappy that their request for PR Mosquitoes had been met from Canadian production, would have been miffed if we'd started sending any aircraft we could spare to Russia.

More on the Russian Mosquito: http://aviation-safety.net/wikibase/wiki.php?id=89126

Edited March 12, 2013 by Seahawk

[davidelvy]

Graham, Ford's Merlins were (unless I'm mistaken) of the Merlin XX generation- 2-speed, but single stage, primarily for Lancs and, I imagine, still Mossies, too. RR's factories were more responsive. But the Merlin was pretty well done by 1945, in terms of Spitfire development- in each case the decision went in favor of the Griffon.

My comment about the Seafire III, Seahawk, was more that this was essentially still a Spit V airframe being built at (or almost) the end of the war- that strikes me as somewhat remarkable. Your point (and Graham's) is good, though- delays of subsequent development, and therefore production, resulted in even more of the same. The fact that "the same" turned out to be quite adequate for the task at hand (mostly) certainly helped.

bob

[Edgar]

Not that I know of; there are photos of senior Russian officers inspecting airframes, but I don't think it went any further. They also asked for 120 bomber versions from Canada, and, from the U.S., 2400 Airacobras or P-63s, 600 B-25s, 300 B-24s, 240 B-17s, 360 Dakotas, 120 C-46s, and 120 flying boats; all of this was over the period of a year from the end of April. They'd also asked for samples of the latest Bristol engines, looking forward to using them commercially at the end of the war. The Air Ministry were generally less than enthusiastic, but we all know what our naive politicians did as the war ended.

Edgar

[gingerbob]

In 1944 Russia "requested" 1200 Spitfires and the same number of Mosquitos, but there was growing resistance to doing too much for a country which was seen as "all take, and no give."

All take and no give? I guess occupying the lion's share of German ground and air forces doesn't count. I know, you were saying that was the perception, not giving it as your own opinion.

Yes, they got one for evaluation, a used Mosquito B.IV DK296 ex GB-G of 105 Sq. Think the Americans, who were unhappy that their request for PR Mosquitoes had been met from Canadian production, would have been miffed if we'd started sending any aircraft we could spare to Russia.

Maybe giving the Americans PR.XVIs and Spit XIs cheered them up a bit? Why (in theory) should Mossies built in Canada vs UK be a problem?

bob

[Seahawk]

Maybe giving the Americans PR.XVIs and Spit XIs cheered them up a bit? Why (in theory) should Mossies built in Canada vs UK be a problem?

In theory, no problem at all. In practice the Americans seem to have regarded them as distinctly inferior to British-built examples. I got the story from a very detailed work by an American on photo recce and interpretation in WW2. The title may come to me!

Edit: it has. World War II Photo Intelligence by Col Roy M Stanley II USAF.

Edited March 12, 2013 by Seahawk

[gingerbob]

Oh great... another book I have to try to obtain! That title does ring a bell, and happens to relate to a very large unanswered question in my mind just now...

I also recall some slurs about Canadian Mossies, but I don't know how much of it is fact-based. I've never really given the Mossie the attention it deserves, which is not to say I have ignored it completely.

bob

[Seahawk]

Oh great... another book I have to try to obtain! That title does ring a bell, and happens to relate to a very large unanswered question in my mind just now...

I got my copy for £5.99 in a charity shop but it seems a little more pricy on the 2nd hand book market. Covers PR across all WW2 combatant nations but majors on the US angle. Some useful diags (eg location of cameras in the PR Fortress) and some useful photos (eg close-up of the camera installation in the nose of the PR Liberator, photos of British, American and German cameras). Also rare coverage of predecessors to the F- series like the O-47 and O-52.

Just don't trust his RN warship identification!