Interesting Essay - Most Strategically Important Aircraft WW2

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A fair crack at a topic that guarantees robustly argued alternative viewpoints.
The PR XIV Mosquito and the PR XVI Spitfire sure sound interesting.
 
Good read

Indeed, puts a lot of stuff into context. Good assessments on each of the aircraft types mentioned - commendably brief but informative, good background and explanation to the purpose of the essay and its aims, and satisfactory conclusions tying the whole together. A+
 
A fair crack at a topic that guarantees robustly argued alternative viewpoints.
The PR XIV Mosquito and the PR XVI Spitfire sure sound interesting.

Excellent post - some details do raise eyebrow, especially the Bf 109 section. Or this (seem like a product of believing the 'source' as a gospel):

By mating two V-12 Merlin equivalents belly-to-belly around a common crankshaft, [37] the Vulture
doubled the engine power output while halving the number of engine nacelles,


Or:
41
The empty weight of the A6M2 Zero was less than 4,000 pounds to 6,500 pounds for the Spitfire IX,
the most capable version of the Spitfire in operational service in 1943. Both were powered by engines of
about 1,300 horsepower. See Pierre Closterman, Flames in the Sky (London: Chatto and Windus, 1956), 49-
58, for a clinical evaluation by a top-scoring Allied World War II ace of the reasons for the Zero's
effectiveness.
 
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It's a very good piece.

Interestingly, the first aircraft I could think of which I might add to his list, and to which he did not allude either directly or indirectly, was the Fairy Swordfish. (Taranto and U-boats.) As the regulars of this forum know, it was much more sophisticated that it looked.

The only other one I'd consider is the Ju88 as a night fighter - I'm surprised he didn't mention that, given its role in the Nuremburg raid. It's the only one of the top ten in production numbers not to make the list, other than the Fw190 which he does discuss.

Best of the rest .... He111, maybe? He's right in general about the twin engined bombers, all much of a muchness. And Pearl Harbor would have had the same basic result with different Japanese bombers. P39 Airacobra did its bit on the Eastern front but again, another aircraft would have had a similar effect.
 
Might I just mention that the Rolls-Royce Vulture engine used in the Manchester was two R-R Peregrines joined in a single cranckcase, not two Merlins.
But this is a fascinating read that I shall return to when I have more time. Well done in finding it and posting it here.
 
Might I just mention that the Rolls-Royce Vulture engine used in the Manchester was two R-R Peregrines joined in a single cranckcase, not two Merlins.

Vulture was not two RR Peregrines joined in a single crankcase...
 
May I enquire just what it was then?

It was an X24 engine.
Angle between the banks was 90 degrees (4 x 90 = 360); if one somehow mates the two V12 cylinders top-to-bottom, the banks will have two times 60 deg angle, and two times 120 degrees. Further, it sported master-and-slave connecting rods (as in the radial engines, and in some V12 engines), not fork-and-blade rods (as with Peregrine). Twinned Peregrine will feature two 1-speed superchargers, Vulture was with one bigger S/C, 2-speed. Reduction gear was all-new. Cylinder spacing was increased vs. Peregrine.
 
It was an X24 engine.
Angle between the banks was 90 degrees (4 x 90 = 360); if one somehow mates the two V12 cylinders top-to-bottom, the banks will have two times 60 deg angle, and two times 120 degrees. Further, it sported master-and-slave connecting rods (as in the radial engines, and in some V12 engines), not fork-and-blade rods (as with Peregrine). Twinned Peregrine will feature two 1-speed superchargers, Vulture was with one bigger S/C, 2-speed. Reduction gear was all-new. Cylinder spacing was increased vs. Peregrine.

Thank you tomo pauk for your explanation. Perhaps I was too general in my original post and I should have said, more specifically, that the Vulture comprised two Peregrines worth of cylinders and pistons in a new crankcase with a new crankshaft. However, my original point remains, the Vulture was not two Merlins "glued" together.

The article that started this thread is still very interesting and makes several good points which I want to read again and think about.
 
...However, my original point remains, the Vulture was not two Merlins "glued" together.

Agreed 100%.

The article that started this thread is still very interesting and makes several good points which I want to read again and think about.

Article is not bad, however I don't think that parts of it should be quoted as gospel before cross-checking with several other sources.
FWIW, just check out mere two points that author has gotten wrong at post #5 here.
 
Agreed that there are some errors in the essay, but the author was someone with a well respected set of academic credentials and overall seems like a solid argument.

Obituary – Professor John F. Guilmartin, Jr.

Agreed 100%.



Article is not bad, however I don't think that parts of it should be quoted as gospel before cross-checking with several other sources.
FWIW, just check out mere two points that author has gotten wrong at post #5 here.

The footnotes clarify the description of the Vulture engine. There are a number of things in the footnotes, not all correct, that clarify some of the questions about accuracy.
 
Agreed 100%.



Article is not bad, however I don't think that parts of it should be quoted as gospel before cross-checking with several other sources.
FWIW, just check out mere two points that author has gotten wrong at post #5 here.

Should I assume that you are referring to the mark numbers expressed in Roman numerals here? I delight in seeing the use of Roman numerals as is correct for almost all wartime RAF aircraft, but I do understand that some people find them difficult to use and would perhaps prefer for them to be consigned to the dustbin of history with the rest of the Latin language. However, my comment about reading the article again and thinking about it concerns the need to disentangle the authors thoughts and beliefs from the facts as he presents them, then find some sort of understanding of his conclusions.
 
Agreed that there are some errors in the essay, but the author was someone with a well respected set of academic credentials and overall seems like a solid argument.

Obituary – Professor John F. Guilmartin, Jr.



The footnotes clarify the description of the Vulture engine. There are a number of things in the footnotes, not all correct, that clarify some of the questions about accuracy.

This is what author says:

By mating two V-12 Merlin equivalents belly-to-belly around a common crankshaft, [37] . . .

This is what footnote [37] says:
37
In fact, the Vulture was based on the earlier Rolls-Royce V-12 Kestrel engine, but with the blocks re-
bored to yield the same cylinder diameter as the Merlin; Victor Bingham, Major Piston Aero Engines of World
War II (Shrewsbury, England: Airlife Publishing, Ltd., 1998), 134-35.


( wrong - bore of Merlin was 5.4 in, bore of Vulture was 5 in - pg. 200 of 'British piston aero-engines' by Lumsden for Vulture)

Then, about mid-war Zero vs. Spitfire IX:
41
The empty weight of the A6M2 Zero was less than 4,000 pounds to 6,500 pounds for the Spitfire IX,
the most capable version of the Spitfire in operational service in 1943. Both were powered by engines of
about 1,300 horsepower. See Pierre Closterman, Flames in the Sky (London: Chatto and Windus, 1956), 49-
58, for a clinical evaluation by a top-scoring Allied World War II ace of the reasons for the Zero's
effectiveness.


So not true.
A6M2 Zero have had barely more than 1000 HP (easily verifiable from host of wartime data found on this site or at wwiiaircraftperformance.org), the SPitfire IX in 1943 have had 1580 HP for the 1942-vintage Merlin 61 (1700 HP for 1943-vintage 2-stage Merlins). Such merlins will do twice the power of Zero's engines at 25000 ft, not just because they sported the 2-stage supercharger - another fact that somehow was not mentioned in Spitfire article in the essay.
The most powerful engine on in-service Zeros were still under 1200 HP.

We have a thing where sources are wrong, and author made it worse by expanding on it. I'm not sure that books written in 1950s are useful anymore as sources, nor that Pierre Clostermann is enough well regarded as a source for cold facts about technical matters.

Let's recall the myth of Japanese carriers' flight decks being choke-full with aircraft (50+ years passed until that myth was busted), that was bought hook-line-and-sinker by Western authors without cross-checking that with US sources 1st. Or many other myths - no supercharger on V-1710 (that got also repeated on 'Decisive weapons' P-51 episode 30 years ago), or that XP-39 went 390-400 miles, or that P-39 was a good attack aircraft etc (we have whole threads devoted to myths in aviation), or that Bf 109G was so clunky that it went just 380 mph.
I don't hold any author above scrutiny, and in case this essay scrutiny is necessary.

Should I assume that you are referring to the mark numbers expressed in Roman numerals here? I delight in seeing the use of Roman numerals as is correct for almost all wartime RAF aircraft, but I do understand that some people find them difficult to use and would perhaps prefer for them to be consigned to the dustbin of history with the rest of the Latin language. However, my comment about reading the article again and thinking about it concerns the need to disentangle the authors thoughts and beliefs from the facts as he presents them, then find some sort of understanding of his conclusions.

No, I'm not commenting roman numerals, but the stuff that is factually wrong.
 
"Moreover, the Bf 109E, the principal version employed in the Battle of France and the Battle of Britain, had the most effective armament of any contemporary operational fighter in the form of two wing-mounted high velocity 20 mm cannon, supplemented by two 7.92 mm machine guns mounted in the engine cowling. The Bf 109's cannon yielded major tactical advantages over machine-gun armed opponents, particularly in fighter-versus-fighter combat."

Here we go again. At least he said 'principal version'. The problem is that a large minority were not armed with cannon during the Battle of Britain, but were still equipped to the E-1 standard.
We know that 100 E-1s were delivered to the units at the Channel coast into September 1940, almost 1 in 3 of those delivered.

Because I have been writing a Battle of Britain diary this year I have recently seen a lot of British Crashed Enemy Aircraft Reports. These invariably list the armament of the downed aircraft and confirm that a substantial minority were armed with machine guns. For example, on OCTOBER 2, No 603 Squadron bounced 8./JG 53, shooting down four Bf 109s in as many minutes. Two of the four were armed with just four machine guns.
 
"Moreover, the Bf 109E, the principal version employed in the Battle of France and the Battle of Britain, had the most effective armament of any contemporary operational fighter in the form of two wing-mounted high velocity 20 mm cannon, supplemented by two 7.92 mm machine guns mounted in the engine cowling. The Bf 109's cannon yielded major tactical advantages over machine-gun armed opponents, particularly in fighter-versus-fighter combat."

Here we go again. At least he said 'principal version'. The problem is that a large minority were not armed with cannon during the Battle of Britain, but were still equipped to the E-1 standard.
guns.

Steve - I read the "Moreover, the Bf 109E, the principal version employed in the Battle of France and the Battle of Britain,..." as 'out of all Bf 109 versions employed in the BoF and BoB, the 109E was the principal version'. FWIW
Also - the "two wing-mounted high velocity 20 mm cannon" excerpt from essay is as not correct, even the 700 m/s MV of the MG FFM does not classify it as 'high velocity' cannon; the MG FF used in during the BoF and BoB was with even lower MV.
 

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