British army create a universal tank class
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marathag
Banned
The multibank was a sop to Chrysler, since Ford and GM had contracts for the other engine types.
Funny thing was, it actually was more reliable than the Radial.
Radials aren't a bad choice, aircooled and light weight for their Horsepower
Sad thing was, the UK had almost the perfect engine in the form of the Napier W12 Lion.
One of my go too darlings for a Brit wank in the 30s is for HMG to give British shipbuilding a major boost
Basically between the wars there was a large number of 'modern' tramp steamers kicking about that were relatively young and therefore very little incentive for their owners to replace them with a larger faster more modern design
The other problem was that the existing dockyards were constrained by the length of slipway between the water and infrastructure (factory buildings, Railway and local housing) which also constrained the modernisation of said buildings
Thirdly due to the age of these 'older ships' many had they been replaced would very likely still be used possibly by another operator and the danger was that the shipping lines would be flooded with older ships making the shipping business less lucrative
So some chap on another website some years back (he and said site are forgotten ???) shared an idea that in the late 20s, early 30s HMG promotes several schemes
Firstly a 'buy back' scheme whereby any shipping company that purchases a new modern freighter or tanker from a British ship yard can sell their old vessel to HMG plus get certain tax break incentives etc for doing so
Secondly the ship building firms are given incentives to modernise their shipyards by 'angling' the slip ways and modernising the buildings as well as only making more modern larger faster freighters and tankers and taking on modern methods such as welding with HMG again subsidising this scheme as well as leveraging superior machinary etc.
Thirdly HMG would only keep those older vessels 'in ordinary' for 10 years after which they would be sold for scrapping - this allowing for an emergency merchant fleet to be retained in case of another world war like the Great war. (obviously once war starts looming these ships are suddenly not being scrapped)
So this has several effects
Britain's Merchant fleet gets incrementally modernised far more than OTL with a number of the legacy Shipyards being modernised and increasingly able to create more modern faster and larger ships - with a far more effective a modern workforce and as other shipping companies and ship yards see the success of this scheme more of them get involved and so on
What does all this have to do with Wielding I hear you say?
Well by the late 30s there is going to be a far larger number of welders in the UK than would otherwise have been the case and while the ship building industries would probably take up the majority of trained welders there would be a larger 'tribal' knowledge and support of it which could be leveraged by the emerging and growing AFV industries in the UK allowing for a superior increase in AFV production using Welding over OTL.
UK produced a good number of 12 cylinder engines - Liberty, Meteor, Bedford twin six for Churchill, plus mated 2x6 cyl for Matilda. Starting early with an unified 12 cylinder engine can yield benefits with regard to economies of scale. US industry was making tanks for the whole free or 'free' world, not a task for the UK & Commonwealth industry.
Nobody used rotary engines on tanks, although it might be an interesting idea for a british-designed tank to have a radial engine.
On a similar theme and going a bit OT but does anyone know if the WW1 Standard N class freighters were riveted or welded?
Fighting the Great War at Sea: Strategy, Tactics and Technology – Norman Friedman
N class standard freighters were made by fabricating parts at inland bridge and engine builders and assembling them at a specially laid out yard. All frames were made straight and the ships sides vertical (bilges were cut off at a 45 degree angle). The hull had a hard chine and the stern was cut off flat. There was no shear between the masts. Turbine (rather than the usual reciprocating) power was planned, with watertube boilers, for easy transportation from distant plants. These ships were called N (National) ships. Eleven ships of N1 design and sixty-six of N design were ordered, most from conventional builders. The only special yard was an eight-berth plant at Haverton Hill (which built the N1 design) approved late in 1917.
Robins, Nick. Wartime Standard Ships (Kindle Locations 784-789). Pen and Sword. Kindle Edition.
The situation had become so bad that in the summer of 1916 the shipowners took it upon themselves to develop the capacity to build their own ships. Lord Inchcape, in charge of P&O and British India, Sir James Caird of the Scottish Shire Line, and others invested £600,000 in a site at Chepstow on the River Wye at which they proposed to build their own ships. A further £300,000 of shares quickly sold to the shipowning community, including Federal and Furness. The site was adjacent to Edward Finch & Company’s shipyard and this was incorporated into what became the Standard Shipbuilding & Engineering Company. Here it was planned to lay out eight large slipways; Lord Inchcape predicted that by autumn 1917 several 10,000dwt ships of standard design would be in frame. It was an attractive location, being close to the Welsh coal fields and the steel works in South Wales, and it was also out of range of attack by Zeppelin.
As it was, government intervention was to upset the plans. Norman Friedman, in his book Fighting the Great War at sea: strategy, tactic and technology, described how government addressed some of the developing issues:
By December 1916 the British recognised that the shipping situation was becoming grim, so they appointed a Shipping Controller with wide powers. He began an emergency shipbuilding programme. The situation was exacerbated by the drastic decline in British merchant shipbuilding during the war, as the Admiralty took over most British shipbuilding capacity. That applied not only to new construction but also to repairs of existing ships. For example, it designed important combatants such as sloops to merchant standards specifically to make use of the large pre-war merchant shipbuilding base. In April 1916 the Board of Trade, which was responsible for shipping, stated that naval orders had effectively crowded out merchant ship construction …
The new merchant shipbuilding programme emphasised foreign orders because they did not compete with the Admiralty for British shipbuilding capacity. After several false starts, the solution adopted in May 1917 was to make the Admiralty responsible for both naval and merchant shipbuilding, so that a single agency could decide how to balance the two. Trade-offs were not obvious, for example, was it better to build destroyers or other craft intended to neutralise the U-boats, or to build more merchant ships to replace those the U-boats sank? Some decisions had already been made. In March 1917 three of the four new Hood class battle-cruisers were suspended specifically to free capacity for merchant shipbuilding. In May Prime Minister Lloyd George took the unprecedented step of making a civilian, Sir Eric Geddes, Controller (in effect Third Sea Lord), with the new responsibility.
On 31 January 1917 Kaiser Wilhelm announced the reintroduction of unrestricted submarine warfare. All ships, British or neutral, became targets when entering the so called ‘danger zone’. It was a calculated threat, made with the knowledge that it might intimidate America to join forces against Germany. The campaign was initially successful, so that between April and June one in four merchant ships leaving Britain never came home. Bernard Leek wrote in Sea Breezes, July 1988:
The bitter experience of the Kaiser’s action finally prompted a positive and effective series of responses. Prime Minister Lloyd George persuaded the Sea Lords to adopt the convoy system as a matter of policy; the decision was taken to arm vessels throughout the merchant fleet; and merchant shipbuilding was belatedly placed upon a war footing. Skilled men were recalled from the colours and formed into Shipyard Brigades and a series of Standard Merchant Ship designs were adopted for construction by both traditional builders and upon purpose built slips in newly created yards in the Bristol Channel.
The latter included the newly laid-out yard at Chepstow, which was taken under the Defence of the Realm Act, without compensation for its owners until after the war had ended. Two other yards were to be laid out, one at Beachley and the other at Portbury. These were the so-called National Shipyards, which had a planned function to build, among others, the innovative ‘fabricated ship’. Government and military bureaucracy then took over and not one ship was completed before the end of the war.
Ultimately, six N-type (N for National) fabricated ships were completed, the first in April 1920, as well as three H-type ships: a poor record for £6.4 million of government investment. The existing shipyards fared much better than the new yards at Chepstow and on the Bristol Channel, largely because of their pool of skilled labour and existing slipways and facilities. These yards were easily able to turn to conventional ship construction to standard designs, as well as production of the N-type fabricated ship.
In July 1917 Geddes announced an ambitious shipbuilding programme of 3.1 million tons, some six times that achieved in 1916. At the same time, attention was turned to standard type ships, but the type and even size of ships was argued between Geddes and the Admiralty. The Admiralty wanted small 2,000-ton ships which would be small targets for submarines to attack and losses would occur only in small units. This argument was, of course, flawed, as it overlooked that the total cost of building five 2,000-ton ships would greatly exceed that of building one 10,000-ton vessel; the same argument also applied to manning the vessels. Friedman again:
The first standardised ships were ordered some time early in 1917 … British policy was … to accept a trial or design speed of 11.5 knots (sea speed of about 10 knots) for most ships but to seek a sea speed of about 13.5 knots if ships of 450 feet length could be quickly and economically built …
Impressive ships though the G class were, the most innovative class was the fabricated, or N-type, ships. The first N type, War Climax, was launched into the Tyne from Swan Hunter & Wigham Richardson’s yard on 8 August 1918; her keel had been laid on 25 February. On completion, she sailed on 7 October from Newcastle to take up duty for the Government Shipping Controller. The class was distinctive and easy to recognise as the ships had a shapeless hull and a triangular transom, both features designed for ease of construction. The last of the fabricated ships was laid down at Caird & Company’s shipyard at Greenock in 1920, but work was later suspended on the incomplete hull. The ship was eventually completed as Grantley Hall for the West Hartlepool Steam Navigation Company and commissioned only in August 1927. She was sold after just four years of service to Russia and given the name Angarstroi. The National Shipyards, however, were singularly unproductive, delivering only six N-type ships between April 1920 and August 1921, long after the war was over.
1934 John Valentine Carden of Vickers is tasked with designing a new Medium tank to complement the new light MKIV........by 1936 the first Medium MKIV prototype is completed and sent for trials.
HMT reluctantly agrees to fund a limited number in early 37 and the 300 ordered tanks are delivered pre war in 38-39. (v OTL 60 Inf MKI + 125 Cru MKI + 175 Cru MkII)
To save money John had used surplus RR Kestrals de-rated to 300hp, after that engine had been abandoned by RAF to concentrate on large engines like the Merlin. John used an enlarged version of the Horstmann suspension as on the light tank to ease training and testing.
Armament had also been got on the cheap in the form of (at first surplus for first 50) Ordnance QF 3-pounder Vickers (47 mm / L50) firing at 2,575 ft/s (785 m/s) and one co axial .303 in Vickers machine gun and a (often missing) Bren on the roof for AA defence.
With protection of 20mm-60mm its was to prove relatively safe for the crew of four, commander, gunner, loader and driver in the opening stages of the war.
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According to Prime Minister Lloyd George
Everyone else who was there remembers it differently
I don't think Welded ships became a thing until the 30s so I doubt that the Standards were welded????
marathag
Banned
Here is my standard post for better UK Tank
Sir John Carden doesn't die in that 1935 crash, but lives
In the test to determine a good engine for the cruiser program, the Napier Lion W-12 was tested, but not accepted, as it could not run on the low Pool Petrol of 63 octane reliably as the older the Liberty V-12
Sir John was not impressed with the new A.12 Infantry Tank specification that the Royal Arsenal was working on in 1936, and knew he could do a tank with nearly the same armor, but better designed and more mobile, based on his A.10
So Vickers has a tank in 1938 as a private Venture, and updated to be a combined Cruiser and Infantry tank, all in one chassis, a 'Heavy' Cruiser 70mm armor basis on the front, 60mm sides and 25mph speed, back to what the A.9 had.
uses the Lion, detuned to run on 70 Octane, as the US Army decided on in 1939 for all vehicles. It gets 400HP, and that engine is still in production for Marine uses, so has availability, and far more power than the AEC Comet 6 cylinder, even though the rear deck had to be slightly raised and angled differently to house it and the relocated fuel tanks
A Three man turret was adapted from the A.10, so the Commander could do his job unimpeded, while the gunner and loader could deal with their job of fighting the 2 pdr or 3" howitzer, while having much thicker armor. It used an electric motor for traverse, mount balanced for the gunner to quickly adjust elevation.
The completed tank is 21 tons. It is 1938, and in trials against the A.12 built by Vulcan is found to be nearly as good protection wise, but twice the speed, but 4 tons lighter. Best of all, Vickers could build cheaper than Vulcan, and in larger quantities, if needed. It was easier to build, with few complex castings.
Some downsides were that the tracks were unreliable, with a number of pins sheared in operation, and the drivers preferred the Wilson gearbox on the A.12. It was decided by Sir John to switch from the 5 speed Meadows to the preselector 6 speed Wilson, and improving the tracks
When War breaks out, Vickers has completed 110 Valentine tanks, while Vulcan has completed less than a dozen A.12 Matilda II
OTL it was worse than that only 2 Matilda II had been completed on the outbreak of war! Only 23 were ready in time for service with the BEF in time for the Battle of France
According to Prime Minister Lloyd George
Everyone else who was there remembers it differently
Indeed....
, I i did read his own biographer thought some of his 'achievements' were suspect......Glyndwr01
Banned
https://en.wikipedia.org/wiki/Wright_R-975_Whirlwind
The Wright R-975 Whirlwind was a series of nine-cylinder air-cooled radial aircraft engines built by the Wright Aeronautical division of Curtiss-Wright. These engines had a displacement of about 975 in3 (16.0 L) and power ratings of 300-450 hp (225-335 kW). They were the largest members of the Wright Whirlwind engine family to be produced commercially, and they were also the most numerous.
During World War II, Continental Motors built the R-975 under license as a powerplant for Allied tanks and other armored vehicles. Tens of thousands of engines were built for this purpose, dwarfing the R-975's usage in aircraft. After the war, Continental continued to produce its own versions of the R-975 into the 1950s; some of these produced as much as 550 hp (410 kW).
The R-975 is most famous for being used as the power plant for the M18 Hellcat tank destroyer, the fastest and most efficient American tank killer of World War II.
R-975 was not a rotary engine, but a radial engine, as it can be read there.
There is an assumption that the Infantry and Cruiser Tank split was a tactically driven choice. What seems to have actually occurred was that the tank industry was tiny. Industrially really tiny. It had to buy it's engines off the shelf and Britain made no really large lorry engines. This left tank designers with two choices from available engine power in the early 1930's. 'Spend' your moveable weight on armour or on speed. You do either but not both. Hence the thick armour slow Infantry tanks and the thinly armoured Cruiser tanks.
It is popular to look to surplus aero engines as higher power choices that would allow a universal tank. If one examines them more closely there were flaws at the time. They were far more costly than road engines and tank money was scarce. They were supercharged so would need redesigning to use low octane petrol without a supercharger so would lose some of that power. The Meteor lost about half its power when converted from the contemporary Merlin. They were dry sumped which is complex and expensive versus a simple wet sump system. Yes one can point to surplus obsolete aero engines such as the Lion but you need to have a supply of parts to keep them going and the surplus engines are out of production. Also their size demands a larger vehicle which puts up weight and cost. The Nufflield Liberty actually makes this point. It was brought into production as part of a huge (by pre war standards) wartime order and the Liberty was reworked and put into new production by Nuffields for that wartime order. There was no way such a thing could have happened pre war. Mention is made of things like surplus RR Kestrels but there were no surplus ones. They were still being used in trainers until into 1944 soaking up the no longer in front line surplus but with no spares back up for major parts.
When rearmament became a real need and money was being made available (with the army the last in the queue) you make more of what you have. sed engines now can enter the scene as they will be affordable (due to need not cheapness) and industry will convert them to suit a tank environment and maintain a supply of spares and replacements. This now frees the designers to exploit the new power in a universal tank but in the 1940s not the 1930s.
The answer to getting a British Universal Tank in the 1930s lies in changing the legislation and practices of the British road transport industry to have them have uses for larger more powerful lorry engines. This would then feed into the OTL situation and the Infantry/Cruiser choices would be unnecessary and they would have gone for a single Universal Tank type whose extra performance would allow a wider choice of armament whilst keeping good armour and speed.
It is popular to look to surplus aero engines as higher power choices that would allow a universal tank. If one examines them more closely there were flaws at the time. They were far more costly than road engines and tank money was scarce. They were supercharged so would need redesigning to use low octane petrol without a supercharger so would lose some of that power. The Meteor lost about half its power when converted from the contemporary Merlin. They were dry sumped which is complex and expensive versus a simple wet sump system. Yes one can point to surplus obsolete aero engines such as the Lion but you need to have a supply of parts to keep them going and the surplus engines are out of production. Also their size demands a larger vehicle which puts up weight and cost. The Nufflield Liberty actually makes this point. It was brought into production as part of a huge (by pre war standards) wartime order and the Liberty was reworked and put into new production by Nuffields for that wartime order. There was no way such a thing could have happened pre war. Mention is made of things like surplus RR Kestrels but there were no surplus ones. They were still being used in trainers until into 1944 soaking up the no longer in front line surplus but with no spares back up for major parts.
When rearmament became a real need and money was being made available (with the army the last in the queue) you make more of what you have. sed engines now can enter the scene as they will be affordable (due to need not cheapness) and industry will convert them to suit a tank environment and maintain a supply of spares and replacements. This now frees the designers to exploit the new power in a universal tank but in the 1940s not the 1930s.
The answer to getting a British Universal Tank in the 1930s lies in changing the legislation and practices of the British road transport industry to have them have uses for larger more powerful lorry engines. This would then feed into the OTL situation and the Infantry/Cruiser choices would be unnecessary and they would have gone for a single Universal Tank type whose extra performance would allow a wider choice of armament whilst keeping good armour and speed.
marathag
Banned
But there was the Napier Lion
Type: 12-cylinder water-cooled W-block (3 banks of 4 cylinders) aircraft piston engine
Bore: 5.5 in
Stroke: 5.125 in
Displacement: 1,461.6 cu.in
Length: 57.5 in
Width: 42.0 in
Height: 43.5 in
Dry weight: 960 lb
Valvetrain: Two intake and two exhaust valves per cylinder actuated via double overhead camshafts per cylinder block.
Cooling system: Water-cooled
Power output: 480 hp at 2,200 rpm at 5,000 ft
Specific power: 0.32 hp/cu.in
Compression ratio: 5.5:1 to to 10:1 on racing engines
Power-to-weight ratio: 0.5 hp/lb
From a 1932 piece on the 'Sea Lion', the Marine version
It is expected to accomplish 300 hr. without overhaul, and the alterations have resulted in an engine of much
smaller dimensions than any known marine type which approaches the " Lion's " horse-power. A long series of experiments
have preceded this achievement, which gives promise of the development of high-speed motor-boats for sporting purposes,
and of boats for commercial work with moderate speed and high power. The size of the " Sea Lion " will also enable it to
be installed in very small boats for racing,for its greatest length is 6 ft. 3 in., overall width 3 ft. 6 in., and height 2 ft. 10 in.
As preparations have been made to convert a large number of " Lion " engines,it should be possible to market them at a
price much lower than that of a new" Lion " aero engine, while the marine version will also be rather more economical
than the aero type. During bench tests,when developing 518 h.p., its petrol consumption was 35 gallons per hr.
The power-weight ratio is approximately 2.6 lb. per h.p. developed, and at 2,300 r.p.m.
the engine yields 500 h.p. Arrangements have been decided upon for the production of the " Sea Lion " at three different ratings,
the lower two being 400 and 425 h.p. respectively. There will thus be a change in compression ratios, with longer life.
A great advantage over engines primarily designed for marine work is gained by the Sea Lion " in its low power-weight ratio, while the
design of its cylinder banks in the form of a broad arrow produces a very compact engine
So that was around, and the aero version since 1922.High Speed Launches were built for the RAFuntil 1939 using the Sea Lion
OTL the Army passed passed on the Lion, since it couldn't run on 63 Octane as well as the Liberty, but in practice, the UKs Pool Petrol was mostly supplied by the USA after 1940, and that was 70 octane that the Lion could run on.
Oh, and they passed on a number of running engines that would have almost been given way.
Brits needed to nut up before the war, and accept that 70 octane would be the new normal for tanks, like every other country that didn't run diesels did
Then they would have had an almost perfect engine for Tanks
Napiers had given up on Lion production in the 1930's except to use up stocks in hand. That was why the army was offered lots of scrap price Lions. Also a new Lion, modified to low octane petrol (which is what it actually began with) was much, much more expensive than two bus engines. The 1930s budget was about either/or. Buy Lions and you have to do without somewhere else so you get fewer tanks.
marathag
Banned
The exact same happened with the Liberty in the end, mostly redesigned by Lord Nuffield, and still not a good engine, as displayed by the Centaur.
Of the around 1000 made, less than 200 saw combat in Europe, as part of Hobart's Funnies, or as AAA platforms. They couldn't be relied on to be mobile for long distances, so were mostly used for training.
UK built a lot of combat near worthless tanks, got for training crews how to deal with breakdowns.
That's false economy at work.
Buy engines that can move a tank around, without breakdowns.
Lion did not have a supercharger, and there was a number of non-supercharged Kestrels making 400-500 HP. Size of both Kestrel and Lion was modest. Nobody said that there was a surplus of Kestrels, they just make a lot more sense than Liberties because of en-bloc cylinders made them stronger. Engine technology moved on from 1918, Kestrel was making better RPM than Liberty. Add together, a much better choice than Liberty, those also needing a steady flow of spare parts that someone must produce.
Nobody said that tank engines can't have superchargers, either.
Answer might also lie in coupling the AEC engine used on Valentine, thus 300 HP vs. ~190 on Matilda.
I would say that the minute numbers of British tanks in the 1930s could not support a special tank engine nor justify the cost of a converted aero engine. I also would say that a Universal Tank needed at least the @300bhp of the Pz IV which was found too little by the end of the war. So it would need to be at least 300bhp and preferably 450bhp. This was not going to happen in the 1930s. There was not the money to build such an industrial investment. 1930 tanks had to have 1930s off the shelf engines. Perhaps something from the marine world could work? The TOG 1 and 2 used the 600bhp Paxman 12TP diesel also used for tank landing craft. Was there anything in the UK in marine engine production in 1935 that could have been the Universal Tank engine?
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