1930's British Tank Transporters

Let us say that Britain releases itself from railway gauge restrictions on tank design by standardising on the Napier Culverin as both a tank engine and as the power unit for a proper road tank transporter.

How might this have impacted upon British tank design?
 
Well the main change is going to be that they're not going to be limited by the railway loading gauge so they can design their new prospective tanks to be wider if they want. That can translate to wider tank tracks so better performance on soft ground thanks to lower ground pressure, a wider turret ring that allows to mount a larger turret on it meaning it's easier to put a larger gun in it and make it a three man turret which is more effective than two men doing several jobs, wider body means more space for the engine which could give you more possible options to look at. The other thing is that if they massively move over to the idea of tank transporters in the 1930s they're going to have a lot more of them which will be very handy as it means less wear and tear, IIRC in the North Africa campaign a lot of the tanks had to be moved about under their own power which ate up maintenance time.
 

Sior

Banned
There would be far reaching impacts if the British Army decided on road transport for Tanks, not just in Tank design!
At the time because of the majority of goods were moved by railways or on costal/canal boats the road infrastructure was sub-standard compared with other industrialised countries. The only straight roads followed the old Roman routes; the remainder meandered over the country side following old cattle tracks. So I could see the Army pushing for upgrades to the roads between Army Camps and Training Areas, and Channel Ports, which would lead to more goods being carried by trucks!
More Trucks on the roads would lead to improvements in the Engines, ignition systems, fuel distribution systems and suspension systems.
This will mean more trained drivers and mechanics for the army to draft which will mean better maintained vehicles in time of war, the majority of mechanics in North Africa were only partly trained.
 
That's a point, IIRC due to prohibitive taxes on lorries over two and a half tons the British manufacturing industry of them wasn't really all that developed to the extent that they had to import critical parts from Germany. I'm also vaguely remembering that at one point after D-Day during the operations in northern France a large majority of British supply trucks had to be pulled from service since they all had the same faulty component, even the replacements and spares, that was traced back to manufacturing faults and bad quality control. Which considering how tight the supply situation was at times can't of been a good thing. Perhaps the railway industry is able to get the Common Carrier freight laws repealed much earlier, which in turn leads to the associated high taxes on heavy lorries being reduced as well?

In an ideal world if they put a lot of time and development effort into the Napier Culverin then it also leads to an earlier introduction of the Napier Deltic, although that might be pushing things a bit too far. :) Fairmile D motor torpedo boats, aka. the Dog Boats, powered by Deltics and the likely modifications they bring would be something to behold. Plus British Rail Class 55 Deltics after the war.
 

Hoist40

Banned
The problems caused for early British tanks by British railway loading gauge is somewhat a myth, it had some truth to it but other factors were much more important.

The early war British A-13 tank was approximately as wide as the American M4. The M4 was taller but this had to do with engine arrangement. Yet the A-13 only had a 2 pounder gun while the M4 had a 75mm and was later able to fit even larger guns using the same turret ring.
The reasons why the A13 was lighter, thinner armor and had a smaller gun had to do with

1. The Treasury not wanting to pay a lot for tanks and the low priority tanks were given prior to WW2 which limited them to around 16 tons

2. The Army with encouragement from the Treasury to settle on using the 2 pounder for both towed guns and tank guns so no work was done on trying to fit larger guns

As to tank transporters as pointed out above you would also have to do something about British roads which would have trouble with large tank transporters. A big problem was that Britain did not have local oil supplies so they taxed anything that used oil instead of coal. Up to the mid 1930’s their heavier trucks were steam powered since they did not need to use oil. So you need to change this policy, probably in the 1920’s so there is time to develop the roads so that tank transporters would be able to operate in the late 1930’s early 1940’s
 

Sior

Banned
Start the oil exploration/explotation start earlier and bigger!
http://en.wikipedia.org/wiki/East_Midlands_Oil_Province

The Isle of Purbeck's oil-shale field, or "Kimmeridge Coal" which has been won from the cliffs to the east of Kimmeridge since the early 17th century, is no longer used commercially.[2] Similar deposits were found at Wytch Farm in the 1890s,[2] but were commercially exploited until only circa 1900, and only at a low level.[2] The Kimmeridge Oil and Carbon Company reported that in 1890 it had dug 5,000 ft of underground tunnels at Kimmeridge on four levels into the local cliffs. There was a local jetty to export the oil shale, and smaller operations occurred at nearby Bencliff Grit east of Osmington Mills.[3]
Isle of Purbeck's oil industry began in 1936 with the first unsuccessful and then experimental wells drilled at Broad Bench near Kimmeridge by D'Arcy Exploration.[2] The area had long been mined for oil shale and tar, but was only prospected for crude oil in the 1950s.[4] It was not until 1959 that a borehole at Kimmeridge showed that oil was seeping out, and 1960 saw British Petroleum's Kimmeridge Oil Well.[2]
 
the A-13 only had a 2 pounder gun while the M4 had a 75mm
To be fair to the A13 the equivalent US tank of the same time had a 37mm gun that was marginally worse than the 2 pounder. By the time the Sherman arrived British tanks were getting the 6 pounder which was noticeably better at penetrating armour than the US 75mm. However, what the army wanted was good HE performance and that is calibre dependent.

Irrelevant information but the poor armour piercing performance of US 75mm warheads were noted as early as the arrival of the M3 Grant into Egypt and the 8th Army began to load them with mixed rounds with captured German warheads fixed into captured French 75mm cases.

Good tank transporters would vastly reduce the wear experienced by OTL British tanks and expand their tactical and strategic mobility as well as post battle recovery all of which are potent force multipliers.
 
Start the oil exploration/explotation start earlier and bigger!
http://en.wikipedia.org/wiki/East_Midlands_Oil_Province

The Isle of Purbeck's oil-shale field, or "Kimmeridge Coal" which has been won from the cliffs to the east of Kimmeridge since the early 17th century, is no longer used commercially.[2] Similar deposits were found at Wytch Farm in the 1890s,[2] but were commercially exploited until only circa 1900, and only at a low level.[2] The Kimmeridge Oil and Carbon Company reported that in 1890 it had dug 5,000 ft of underground tunnels at Kimmeridge on four levels into the local cliffs. There was a local jetty to export the oil shale, and smaller operations occurred at nearby Bencliff Grit east of Osmington Mills.[3]
Isle of Purbeck's oil industry began in 1936 with the first unsuccessful and then experimental wells drilled at Broad Bench near Kimmeridge by D'Arcy Exploration.[2] The area had long been mined for oil shale and tar, but was only prospected for crude oil in the 1950s.[4] It was not until 1959 that a borehole at Kimmeridge showed that oil was seeping out, and 1960 saw British Petroleum's Kimmeridge Oil Well.[2]

Trouble is any move towards oil is going to meet resistance from the coal industry and its friends

If you google 'The British Marine Industry and the Diesel Engine' by Dennis Griffiths, there is quite a good article on how coal intrests influenced what happened in the marine engines industry and I don't see it changing much for land engines.



Internal combustion engines were of interest to the Admiralty for use in submarines and a number of designs were investigated. In March 1917 a two-cylinder experimental Fullagar oil engine failed to impress the Admiralty, but their Lordships indicated a willingness to order at least two of the 1270-kW version upon satisfactory testing. This was built by Laird and successfully tested, but when the war ended the Admiralty decided not to pursue the idea. A considerable amount of investigative work was undertaken into internal combustion engines by the Admiralty Engineering Laboratory and a number of different engines were tried, including a single-cylinder Doxford opposed-piston engine procured shortly before the end of the war. The idea of an opposed-piston submarine engine was abandoned in favour of a more conventional single-piston four-stroke design.

During World War I the needs of the nation were paramount and development on large British diesel engines had a low priority. But no such restrictions applied to major overseas competitors such as Sulzer, B& W or Werkspoor, all of which were able to improve their designs. With the coming of peace, there was an apparent need for merchant shipping that could not be met fully by tonnage released from wartime duties. British yards, in general, met the demand by building traditional ships with steam- reciprocating machinery and coal-fired boilers. By the early 1920s, however, the boom had ended and the demand for tonnage plummeted. In the new climate ship-owners wanted efficiency and low operating costs, which the large crosshead diesel engine could by then offer. Most British yards lagged behind their overseas competitors and there was antipathy towards the internal combustion engine despite its obvious advantages.

Arguments against diesels emanated mainly from Britain and were particularly vociferous from coal interests. From the early 1920s, adoption of diesel propulsion was almost exclusively at the expense of the coal-fired steamer.

Diesel engines did make sense economically as far as many ship-owners were concerned. In 1925 Furness Withy, a major British ship-owner that favoured motorships, ordered five from Deutche Werft on the grounds of cost alone: the price of £150,000 per ship was £60,000 to £100,000 per vessel less than British tenders. Its Chairman, Sir Frederick Lewis, was willing to give the order to any British yard able to quote a price even £10,000 per ship more than the Germans, but there were no offers. The ships thus had German rather than British diesel engines.

Overseas yards quickly adopted the diesel and were in a position to offer it to any owner who expressed an interest. Tonnage built in British yards tended to be steam- powered while the rest of the world increasingly favoured diesel. The complacency of shipbuilders on the northeast coast of England with respect to the diesel engine was attacked in a 1920 editorial in The Motor Ship, which opined that "they do not want the motor ship to progress because it would mean that they would be driven out of their complacency and [they would be] forced to deal with something new."

Although some shipbuilders argued that they held no brief for any particular engine, the magazine's editor, A.P. Chalkley, found himself barred from several shipyards and contractors were warned not to advertise in The Motor Ship unless they wished to risk future orders. As late as 1924, Readhead and Sons, the Tyneside shipbuilders, claimed that the reason they did not offer diesels was that owners were not interested. The fact is that Readhead's engine shops were only capable of building steam and the firm never took a licence to build diesels.

The Influence of Coal

Many arguments were put forward in favour of the steam engine, but the champions of steam were really battling for the British coal industry, which had suffered in the postwar period. Markets for coal had been lost as competition from other suppliers increased.

In 1928 Sir William Noble, chairman of the Cairn Line, which owned nine steamers and no motorships, indicated his lack of understanding about engineering when he commented that the diesel was only a fashion, which he expected "to give another turn of the wheel and a normal increase in world consumption of bunker coal to be resumed." As well as being a prominent ship-owner, Noble was also a director of the Blackwell Colliery, but his role as President of the UK Chamber of Shipping placed him in a very influential position. C.W. Cairns, also of Cairn line, likewise joined the battle between coal and oil. "There are other ways in which coal can help in its fight against oil," he wrote, "such as the adoption of geared turbine outfits...[T]he diesel engine has got very vocal support whilst those who ought to uphold coal say little."

Arguments against the diesel and in favour of coal were even made in Parliament. Sir Robert Thomas came out firmly on the side of coal, although his remarks betrayed a lack of understanding of marine engineering and shipping. "The internal combustion engine has had its day," he argued, adding that "he was sorry that so much British capital was sunk in it." Moreover, "he believed that the future of propelling power for ships would rest with pulverised coal. That would mean not only an enormous saving in the running of ships but also be of great help to our coal trade." Another champion of steam, and hence coal, was the eminent naval architect Sir John Biles. In a 1925 paper to the Institute of Naval Architects (INA), Biles advocated steam for practically every type and size of ship; to advance his cause he used estimated costings for steam plants, which were then still at the development stage, and compared them with operational data from early diesels. Throughout May, a rather heated debate was carried on over the diesel in The Times among Lord Bearsted, chairman of Shell Transport and Trading; Lord Invernairn, founder of the shipbuilders Beardmore; and Sir Fortescue Flannery, a respected naval architect. A year later Biles presented a second paper to the same learned society in which he made some extravagant claims for steam at the expense of diesel. A third paper followed in 1928, this time addressing the question of fuel. Again absurd claims were made, and during discussion of the paper a number of people questioned the validity of the data. One individual commented that Biles' "diesel figures appear lacking in foundation." Sir John admitted his real motives when he told an opponent that he might "monopolise all the prophesying he likes so long as he helps to increase the use of British coal in place of foreign oil."

The general argument against marine diesels was that they burned imported oil rather than British coal. British shipbuilders were encouraged to stay with steam instead of diesel and they did so (figure 13). Despite being the world's major shipbuilding and shipowning nation, in the interwar era Britain's share of the world motorship fleet barely changed.

Economic Advantages of the Diesel Engine

There was no doubt that, except for express passenger liners, diesels offered greater fuel and space economy. Indeed, in 1924 no less a personage than the Chief Superintendent Engineer of Blue Funnel admitted that "oil for marine purposes has come to stay."

Although diesel engines weighed more than steam-reciprocating engines or turbines when the weight of the boilers was taken into account, actual operating weights for similar steam and diesel plants were much the same (see appendix table 9). The space occupied by bunkers in a diesel-engined ship was much less than for a steamer of similar operating range, while the length of the engine room in the former was shorter per unit of power than in the latter. Diesels also required fewer engine room hands, although capital costs were higher, and these had to be recovered during the working life of the ship through higher charges.

Appendix table 12 illustrates estimated operating costs for low- and high-powered ships based upon 1920 figures, while appendix table 13 compares working costs and cargo earnings for typical ships in 1922 and 1926. Only Blue Funnel published actual costs for ships in its fleet, and this information confirmed the economic superiority of diesels. One area of shipping in which Britain was firmly established and in which the steam- reciprocating engine reigned supreme was the tramp sector. Information provided by a major Danish operator in 1921 showed that even here diesel-driven ships were the most economical. As one shipbuilder put it, "within twenty years all tramp ships will be equipped with Diesel machinery."
Fuel costs and cargo space were important to operating profits. Since diesel-driven ships could carry fuel in double-bottom tanks, and their engine rooms were shorter than in steamships, they generally had a greater carrying capacity. In general diesel ships could travel further without bunkering than steam because of lower fuel consumption. For global trade, fuel supplies were difficult to guarantee, but as the diesel could travel farther before bunkering, it was possible to take on fuel at the cheapest ports along the route.34 During the 1920s the number of ports at which diesel-grade bunker oil could be obtained gradually increased, thereby further reducing the advantage of coal on certain routes. Appendix table 15 illustrates the relative costs of coal and fuel oil at world ports in the 1920s.

Many countries, including Norway with its expanding fleet, had no indigenous fuel supplies to protect. For these nations, self-interest lay only in making a profit from shipping. As a result, almost all Scandinavian tonnage built after 1918 was powered by internal combustion engines. Germany lost many of its coal-producing regions and much of its merchant tonnage as a result of the war; it, too, quickly adopted diesel propulsion.

Some British owners also shifted to diesel, and the number of motorships in the British fleet increased. Yet it was not until close to the outbreak of World War II that British shipyards approached parity in terms of motor and steam construction (see figure 12). While the depression of the early 1930s restricted investment in new tonnage and induced owners to retain older and less efficient coal-fired steamers, by the time the economic downturn ended few British crosshead diesel engines were being produced.

Conclusions

During the 1920s a number of British crosshead diesel engine designs evolved but most failed to make an impact as many domestic owners were encouraged to stay with the coal- fired steamer. There were many reasons why these British engines failed to succeed, including technical faults and high initial cost, but the lack of orders limited the funds available for development. Not all British engines were technically inferior, either: the Swan Hunter Neptune and Scott diesels certainly had potential, although the shortage of development funds was a definite hindrance. Moreover, the relatively high initial cost of the diesel compared with steam must have deterred many British owners and discouraged some overseas owners from fitting British-designed engines which might be more expensive than continental designs due to limited production runs.

Continental designs such as B&W , MAN , Sulzer and Werkspoor received orders because their shipyards built more diesel than steamships and because some British engine builders licenced them rather than developing their own or taking licences for other British engines (see appendix table 16). Many British designs failed to attract licences because the owning concern did not actively seek out such opportunities; even Doxford, builders of the most successful British marine diesel, did not attempt to attract licensees, although it was willing to grant permits upon application.

Had there been more orders from British owners for motorships in the 1920s, it is highly likely that the British marine diesel engine industry would have prospered and the domestically-owned shipping industry would have been more profitable due to lower operating costs. The fact that Britain had such vast reserves of coal probably hindered its marine engineering and shipping during the interwar years, much as it had helped to induce technological change in the nineteenth century. The influence of the coal lobby certainly reduced the market for British diesels in the 1920s, as many ship-owners and even some shipbuilders were encouraged to stay with steam in the "national interest."

Poor management often resulted in money being wasted developing engines for which there was little or no market, while in other cases insufficient finance was made available to test worthwhile products. British diesels were essentially developed by shipbuilders who failed to realise that the engine was simply a device for propelling the ships they built and that their main function was shipbuilding. Diesel engines were much more specialised than steam and had to be designed and developed by specialists; this was the way that the successful continental firms, such as Sulzer and MAN , had done it. British shipbuilders wanted to design and build the entire product when they should have concentrated on shipbuilding and relied upon specialist designers for the propulsion. At a time when orders were limited by the postwar recession and the reluctance of many British ship-owners to switch to diesels, it was folly to invest in engine development without attempting to create a market through a system of licensees. Yet only Doxford adopted this policy, and then in a half-hearted manner compared with the Europeans. Still, it was the Doxford engine that carried the torch for British diesels into the post-1945 era.

The failure of the British shipping industry to embrace diesel propulsion put domestic engine builders and shipbuilders at a comparative disadvantage. Had the nettle been grasped early enough, these industries might well have been in a stronger position to survive the upheavals of the 1970s and 1980s. The same can also be said of the British shipping industry.
 
Well, perhaps the POD could be the Admiralty going ahead with the Laird design post-WW1. That article says that they were interested but decided not to pursue it after WW1. With the Admiralty pursuing the design, and use of oil-engines, that could then have knock-on effects with other areas, such as land engine designs.
 
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