Sunday, June 9, 2019

A Technological Appendix to Postblogging, March 1949: HMS Queen Elizabeth II

In this sixty-eighth year of the reign of our sovereign majesty,Queen Elizabeth II, she has been honoured by a warship carrying her name. 



Also, your humble correspondent has agreed to work a fifth day this week to address my employer's ongoing, critical labour shortage, prior to working another three straight next week so that I can have my days off together. Under the agreement imposed by the Special Officer last December, I am working 9 1/2-hour, four day weeks as some measure of compensation for the theft of my paid accumulated time off benefit under said award, thus the additional overtime commitment, and a physically gruelling, if otherwise none-too stressful work week which has left me unable to complete a postblogging installment. And also entirely unable to understand how the management of a professionally run, national corporation thinks it appropriate to alienate its labour force in a chronic, endemic labour shortage. The best excuses I can come up with involve some kind of combination of fiscal exigencies and institutional blind spots. 

And, thus, now, super-carriers.

Because I have messed up my schedule for the benefit of ten hours of overtime, this post comes prematurely.  USS United States, the first super-carrier, won't be cancelled until next month's postblogging,  on 23 April 1949. All we have this month are advanced intimations: Lord Trenchard blithering about aircraft carriers in the Lords, someone agreeing with him in the pages of Flight, and an early appearance by Christopher Mayhew, the future Labour Undersecretary of State for Defence who would resign in protest of the cancellation of Britain's CVA-01, the first (or second, depending on how seriously you take mid-Fifties schemes) attempt to honour Her Majesty by attaching her name to an aircraft carrier even more magnificent than the battleships that had carried the names of her forebears, with the exception of her father, upon whose objections King George VI became another King George V.
Very pretty, very Buck Rogers. 
You can take these rumblings in the British press as some kind of preliminary to the cancellation. There's something wrong in the world of carrier aviation, and it is not just hindsight that sees it. The bizarre Navy press release cited by Flight, reminding us that one Lockheed PV-2 had flown off a carrier deck, and that another had set a world distance record (before being repeatedly upstaged by B-29s) is more than just an example of the technical press's annoying habit of repeating the same news story over and over again. The Navy wants it out there, and it is no coincidence that it comes shortly after James Forrestal's 31 March 1949 resignation as Secretary of Defence. As appalling and inexplicable as I find contemporary official Washington's inability to intervene in Forrestal's ongoing sufferings from bipolar disorder, there is no question that the Navy preferred to read the resignation as evidence that the Administration had turned against it. The new Secretary, Louis Johnson, was by that reading Truman's hitman, sent to euthanise the supercarrier, among other things.


Per Wiki, the Navy continued to press for a near-future nuclear role, which would entail Neptunes carrying versions of the narrow-diameter "Little Boy" enriched uranium bomb, taking off from existing aircraft carriers with the help of a lot of JATO power, and ditching at sea on returning from their strike. Since Neptunes were far too heavy and had far too great a landing or takeoff speed to use either catapult launch or arrestor stops, this was the only way to put a nuclear bomb in the air from a carrier, and you do not have to be a callow former senator from Missouri to see a service in search of a role.

That is, if the Air Force can do it better, and as we've seen from the extended contract for B-36s, now to be equipped for mid-air refuelling in the same way as the B-29s which have just flown around the world, that argument has been accepted. It's not that the B-36 programme isn't itself horrifyingly fudged. Only a lunatic would accept the hanging four jet engines off the already-fully engineered wing already loaded with troubled R-4360 engines,* was anything more than a desperate expedient pending the development of something --anything-- that could deliver an atomic payload of 10,000lbs to strategic targets in the depth of Mother Russia.  And hopefully said  lunatic would be detained for some good old fashioned shock therapy if the argument continued after the Valentine's Day disaster of 1950, in which a B-36 was forced to eject a Mark 4 nuclear bomb before crashing into Mount Kologet, which for some reason has an entry on Deutches Wikipedia.**

We're admittedly still months away from the first peacetime loss of a "nuclear device" in an attempted self-bombing of the Christian West, but the loss of one of the B-29 tankers on the round-the-world flight is perhaps a fair advanced warning of the exciting times ahead for USAF B-36 crews. Although the military type's loss rate doesn't rise to the inglorious heights scaled by the similarly-engined Stratocruiser, with thirteen hull losses out of 56 completed. I also can't help noting one state-owned socialistic hull loss to seven for flag-of-free-enterprise-bearing Pan Am. I guess I'm just objectively pro-Communist.

Leaving the vagaries of giant-aluminum-overcasts to return to the even more exciting world of taking off from aircraft carriers by throwing bombs behind planes that weigh more than three times the maximum allowed for by the designing naval architects, we come to the planned replacement for the Neptune, the North American AJ Savage, admirably truculent in visual design and powered by a more reliable plant. Although the fact that "two of the three prototypes crashed during testing" doesn't exactly fill me with confidence in the design. Taking off at 51,000lbs, it would have been another JATO baby. As already noticed in the technical press, it had nothing like the range or speed to penetrate serious air defences. On the other hand, it could carry the then-standard Mark 4, a composite enriched-uranium plutonium implosion ("fat") bomb with a levitated pit and a capability of 31 kt compared with 21kt for the original Fat Man.

The Wiki, if you follow the link, notes that the Savage wasn't a particularly popular aircraft on shipboard. I'm sure I'm grossly exaggerating the fire risks involved with JATO launches, but the fact remains that they took up a lot of space on the Franklin Roosevelt-class and modified-Essex class carriers that carried the 140 examples in their short service careers. United States was supposed to alleviate those issues.

The problem is that it didn't. In spite of displacing 83,000t full load, being fully a thousand feet long,  carrying a complement of 5500, and costing an estimated $189 million, United States was designed to carry only "12 to 18" heavy bombers. And although there would be room for 54 jet fighters for fleet defence, the bombers dominated the design. The design shows a series of exigent compromises in pursuit of bomber capability. It would have been a flush deck, and the problem of puncturing the deck with an elevator large and powerful enough to take the Savage, never mind its gargantuan planned A3D successor, was solved by using a deck park and omitting the hangar volume required to take the bomber squadron at all. Even once these compromises were accepted, more had to follow. United States would have very limited weapons storage, on the assumption that there would not be an extended maritime campaign after an all-out nuclear exchange, this being before the invention of "broken back war" to cover the felt need for a large conventional armed forces in the age of the atom. been a cramped and limited ship. The one thing that flummoxes me here is that United States would have been able to launch aircraft from catapults and receive them on arrestors, implying a new generation of both with the capacity to take the Savage and Skywarrior. This is an enormous ramping up of the power of existing hydraulic aircraft catapults, which were already struggling to put heavily-laden late war aircraft into the air with the kind of gentle smoothness that might reasonably be asked for in the handling of atomic bombers.

I went over Flight's visit to the still working-up HMAS Sydney rather lightly last month, but here's a link to the online article, which describes the contraptions that the Australians were dealing with 1949.  A ram pump compresses a glycol-water mixture at 2400lb/sq inch, some of which squirts into an accumulator to provide power to restore the catapult to launch position, while the rest puts a torque on a "complicated arrangement of ropes and sheaves" that assures the comparatively gentle buildup to a alacritous launch. In the 1947 RAeS discussion in which W. S. Farren proposed some kind of catapult powered by the ship's own machinery, Commander Torrens-Spens noted that a catapult could achieve a 30 second launch, but that was with aircraft limited to an all up weight of 1700lbs. Commenting, the then-Director of Naval Construction, Sir Charles Lilliecrap, noted the additional requirement of a terminal speed much greater than the current 66 knots, while Admiral Slattery complained about excessive restrictions on naval aircraft design due to the limits of catapults and arrestor gears, as well as the better known constraints imposed by hangar heights and elevator widths and weights.  There is nothing in discussions of United States to suggest that the USN had really grappled with these issues. I've just soldiered through an entire retrospective analysis that dwells on everything from personality to strategic doctrine without even the least attention to these technical issues. Although I do not get a favourable impression that the US Navy's postwar leadership.

As an issue of naval architecture, this is perhaps not as surprising as I make it out to be. At the outbreak of the war in the Pacific, the Royal Navy had less than a year's experience of its preferred fleet aircraft carrier, the Illustrious-Implacable classes, while the USN was still waiting on its first Essex. Illustrious would become notorious for its cramped and inadequate aircraft accommodation even before the first intimations of the Essex-class' grotesque vulnerability were absorbed.

I have a nice splatbook of British carrier designs at hand that tells me that, by the outbreak of war, the 1941 "repeat Implacable" had evolved into the largest aircraft carrier design in hand in the world. It's hard to speak of a final design for the ship that eventually became HMS Ark Royal (R09), since the ship was in the process of becoming for virtually its entire career,  but by the time the keel was laid on 3 May 1953, it was a 36,800t standard displacement ship with a length of 804ft and a large enough air complement to justify the maniac ambitions of the Fleet Air Arm, which by that time had ordered the Barracuda Spearfish, Sturgeon, Firebrand, Firefly, Wyvern and Sea Fury on schedules that were likely to  overlap and required the navy's air force to operate in excess of five types simultaneously in sufficient numbers to justify production economies of scale.


Well, that and the 6 other fleet and 24 light carriers the Admiralty had ordered by that time. It probably says enough of this that the final class of 8 Hermes-class light carriers (as big as Illustrious notwithstanding the "light" in the title) was supposed to complete in 1946 and presumably be available for the 1947 VJ Day victory celebrations. Amongst this gargantuan crop of too-late ships were an interesting convergence of American and British dissatisfaction with their respective standard carrier: Ships big enough to carry planes Essex-style and deck armour, Illustrious-style. In the event, the Royal Navy was never to receive its mighty Maltas, but  three Midway-class carriers of the same vintage, laid down in 1943, were completed between 1945 and 1947. The Admiralty was jealous, but, given the lack of steel and labour in 1943--44 due to the distraction of D-Day, the Maltas never advanced to the point of being laid down, a status that did not save Ark Royal's third sister ship, broken up on the slips in spite of being 28% complete. In light of my ongoing campaign of revisionism against the idea that postwar cuts in defence procurement were due to Britain being "broke," it is worth noting that even my source, naval architectural historian David Hobbs, admits that the reason was the shortage of steel and dockyard labour.

Meanwhile, whatever you can say about the Midways being wet and cramped ships, their 45,000t displacement and 968ft overall length provided them with the space to operate Neptunes and Savages. Just as importantly, the armoured deck provided the foundations for sufficient reinforcing to allow the decks to support their weight. The general objections to flying off 60,000lb aircraft already noted, it was something that the Midways could do, which at least made the case for the United States that much weaker.

The launch of Ark Royal, upcoming in March, 1949, came in 1950, but by this time it was seen as only a trial launching. Wartime experience had left the Fleet Air Arm enamoured of the sidelifts that allowed the Essex-class to raise and lower aircraft without opening a giant hole in the middle of the flight deck. A significant redesign was needed to add a sidelift to Ark Royal, so back to the shop went she.
By Photo: Royal Navy/MOD, OGL v1.0, https://commons.wikimedia.org/w/index.php?curid=28824042
By this time the ship had acquired the angled flight deck that is such a distinctive feature of the modern aircraft carrier, which more-or-less rendered the sidelift irrelevant. Together with the mirrored landing aid, which is something of a misnomer for an elaborate optical computing device the size of a large traffic light, and the steam catapult, the angled deck transformed the possibilities of the aircraft carrier and . . .

The red-headed stepchild of the Fleet
Ahem. Steam catapult. I know, I know, it sounds . . . boring. Naval architects fseem to ind it especially boring. The best that Mr. Hobbs can do is tell me that work on the steam catapult began "after 1946," that a trial installation on HMS Perseus did 1500 test launches "in 1950," that HMS Hermes was slated to receive the first operational steam catapult in 1951, and that Perseus went on tour to the United States in 1952. There, the Navy's newer and less radical supercarrier, the Forrestal, allowed under the new and more generous regime of a post-Korea Defence Department, had been ordered on 12 July 1951 and laid down on 14 July 1952. Forrestal was modified during construction to take a steam catapult and angled deck, and entered service in 1955, a year after the refitted Essex-class Hancock, as near as I can tell the first of that class to be fitted with a steam catapult, although it's as Byzantine as heck. Hermes, launched in 1953, was finally commissioned in 1959, being overtaken as the first British steam catapult carrier by Victorious,  a refitted Ilustrious-Implacable fleet carrier with a career that I can best compare with HMS Vindictive, the British carrier no-one ever talks about.

. . . And that's where I am. The information on steam catapults in published sources is so scant that I was wondering if some draconian 75 year classification had been imposed on them for reasons perhaps having to do with things silenced and atomic, but there it is at Kew, a massive fonds on the development of the steam catapult in an open holding.  To be fair to the naval architects, it might still have been classified when Henry Chapman published "The Development of the Aircraft Carrier" in Trans. Roy. Nav. Arch. 102, 4 (October 1960): 495--533. Chapman and the discussants are fairly forward about arresting gears, including a failed Japanese electrical arresting gear, but trail off into mumbles when the steam catapult comes up.  So, if classification s the explanation, tand the naval architects have been copying each other ever since --Wait, that's not fair at all.

So here's what Chapman does say:

Pushing 30,000lbs of aircraft along at more than 4gs is pretty clearly a concern for the naval architects tasked with building a structure that can withstand this stress (and the even more spectacular transient stress of the catapult resetting), but the details are left obscure by both Chapman and numerous discussants. The (weak) Wikipedia page  comes very close to attributing the invention of the steam catapult to Colin Mitchell, a well-connected MacTaggart Scott executive who was seconded to the Admiralty in WWII, according to an embarrassing biographical page. While the involvement of MacTaggart Scott is pretty much to be expected, and the extant biographical material (here's a link to the more serious Proc. Inst. Mech. Eng. obituary via Grace's Guide) brings out the influence of the Germans' V-1 catapult launch system, which might have been expected, the rest is left completely obscure.

On the other hand, my fonds search turned up a number of studies on the catapult's steam accumulator. I even get a strange error message that might (tinfoil hat time) indicate that they are still classified. While there's nothing particularly new about using steam from the boilers to run marine auxiliaries, that many free-standing papers, might suggest that there is something to pursue.
CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=532511
The modern steam accumulator is associated with steam districts and is more on an architectural than a naval architectural scale, but they were key to the fireless locomotive that navigated tunnels, mines and factories before electrics, and which might have a second life in modern times. Again, I'm not getting why they would have been problematic on shipboard, but it seems that they might have been fire hazards due to slipping mechanisms. Perhaps the installations  used large amounts of asbestos? Shh!

So that's where this investigation stands for now, and a good thing, too, as I have to start getting ready for work. At least the possibility that the Engineer-in-Chief was the unsung white knight who saved the aircraft carrier at some point during 1950, no Korean War required. We shall see as developments proceed.
_____
*Presumably everything is so vague because everyone is hoping that the VDT Wasp Major will work out. Unfortunately, the VDT is something of a sandbox innovation, in that the industry dropped it in the sand, pawed a good covering of dirt on it, and walked away, never to comment again. The turbo-compound engine has been proposed and redeveloped many times without making much of a production splash. Although the Russians put them in over 400 missile boats?

**"Three years later, an RCAF flight searching for the missing de Havilland Dove aircraft of Texas millionaire oilman Ellis Hall spotted the B-36's wreckage.[6] It was found on the side of Mount Kologet, about 50 miles (80 km) east of the Alaskan border, roughly due east of the towns of Stewart, British Columbia and Hyder, Alaska, on the east side of the isolated Nass Basin northwest of Hazelton, British Columbia.[2]

3 comments:

  1. Friedman discusses steam catapult development in typically mind-numbing Friedmanesque detail in *Fighters Over The Fleet*

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  2. I'd like to say, "And so he does," at this point, but it looks like "at this point" is going to be in a week or three, because this latest Friedman opus is available to me as an iPhone Kindle edition, than which there is nothing less browsier. Only $18 Canadian, though, so I shouldn't complain.

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  3. It's a worthwhile read in many ways.

    His explanation of going from 1000 hp piston engines to 2000 hp piston engines was an eye opener for me for example. "Only" gains you 100 mph or so of speed because of propeller physics, but enables you to carry a lot more fuel/weapons/armour. Thus making it harder to get you on & off a ship. Etc.

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