WAR SUPPLIES

Wairarapa Times-Age, 14 March 1940, Page 4

WAR SUPPLIES

MANUFACTURE OF TANKS MIRACLES IN A ROBOT WORLD. BRITAIN’S SUPREME EFFORT. The mechanisation of a suddenly expanded army has thrown on British industry a strain as great as that involved in the expansion of the R.A.F.. micl.it was to observe progress on this •■front" of what has been called the ■‘War of Industries” that 1 visited some of the factories and discussed their problems with military and industrial experts, writes the London correspondent of the "Sydney Morning Herald.” Tanks, machine-gun carriers, infantry trucks, and artillery tractors are among the equipment which now has to be turned out on a mass scale. Industry has responded so rapidly that one factory alone is turning out as many army lorries in a day as the whole Army had in 1914.

In another factory, which had been suddenly switched over from the manufacture of commercial vehicles, I saw three assembly lines on which 18 different types of military vehicles were taking shape as they journeyed through the works on chain tracks moving at two feet a minute. There was also a sprinking of commercial lorries for export, and altogether one vehicle was leaving the factory every 10 minutes.

Outside a completely new factory, specimens of its latest products were performing circus tricks in an arena of mud. Cruiser tanks and Bren carriers reared up and slithered down again over a 10ft pile of slag. They undulated without bumps or pauses across a row of logs spaced out at about half the length of a lank. They negotiated pits, raced through water, and turned in their own length at top speed. Inside the factory, line upon line of powerful engines and armourplated bodies in various stages of assembly were moving in a steady stream through 17 acres of clattering machinery. To understand in greater detail the manufacture of tanks and military vehicles, one must look at it in perspective against the general background of the mechanisation problem. VARIETY OF TYPES. The Ministry of Supply is responsible for supplying to the Army all the various types of mechanically propelled vehicles it requires, and to this end has enlisted the co-operation of industrial firms, including some motor car manufacturers whose peace-time products are well known in New Zealand. The wheeled vehicles —as distinct from tracked vehicles like tanks —which they have to supply include motor cycles, light cars, heavy cars, infantry trucks, machinery lorries, searchlight lorries, mobile offices and sterilising plants, mobile laundries and laboratories, four-wheeled field artillery tractors, anti-tank gun carriers, ambulances, mobile workshops, wireless trucks, water tanks, six-wheeled load carriers, workshop stores, winch lorries, and anti-aircraft tractors.

For these, about fifty different types of bodies have had to be specially designed. Design begins with the re.quirements of the General Staff, and those requirements begin with tactical considerations. These considerations make it necessary for designers to keep constantly in mind the possible need for rapid adaptation of production. For example, changes in the nature or locality of warfare may require changes in transport. Again, the production by the enemy of a more powerful anti-tank weapon would necessitate readjustments in the design of tanks. Tactical considerations determine such vital matters as the type of weapon that has to be carried on the tank and the size of the, enemy weapon that has to be kept out. These requirements of armament and armour have to be balanced against tactical requirements of performance, such as cross-country speed, circuit of action, trench-crossing capacity, and vertical climb. Again, the tactical consideration of space required for ammunition stowage must be balanced with space required for a given number iff crew. CONFLICTING CLAIMS. These seemingly incompatible requirements are not beyond the ingenuity of British designers, but the result is a very complicated job that has necessitated the training of engineers and skilled workers. Up to 1936 largescale production of tanks had not even been planned, and in normal times firms cannot afford to give undivided attention to work of this nature. Yet the problem has been solved. The trickle of production that began two years ago has swelled into a steady flow for all the units of the "land navy”; scout cars and armoured cars, which correspond to torpedo-boats and light destroyers; tight tanks, the destroyers; cruiser tanks, the cruisers; infantry tanks, the battleships. The tank factory which I first visited is entirely new, and was built and equipped specifically for the production of tanks and machine-gun carriers. Building operations began in June, 1937, and the first delivery of machine-gun carriers was made at the end of the following May. Since then deliveries have gone on without interruption and at a progressively increasing rate.

At the time of my visit the main energies of the works were being directed towards the production of “cruiser” tanks in increasing numbers. The engineering company which is in charge of the production has specialised in the development of jigs and tools for this type of tank, in conjunction with the Mechanisation Department of the Ministry of Supply. This type of tank is also being manufactured by other tank constructors, for whom the company is producing the engine, gearbox, and other transmission parts.

The problem of organising this factory for smooth production on a large scale may be gauged from the fact that the tank has 6,200 detail parts requiring 50,000 different machining and assembling operations, yet throughout the 17 acres of machinery it seemed that not ode piece of metal could be out of place and there was never a sign of even a temporary hitch. INSPECTION AND ASSEMBLY. The work of the inspection department gives some idea of the delicacy of mechanism in these apparently clumsy monsters. Even heavy rods must be accurate within a quarter of an ounce. There are special machines on which all clutches, flywheels, and engine fans are balanced to eliminate vibration when rotating at high speed. About half-way through the engine assembly section one sees rows of en-

glues beginning to take shape—crankshafts and connecting-rods being fitted into crankcases, cylinders, timinggears, and other units added in an orderly fashion until the complete engine with fly-wheel and clutch leaves the section for the engine test. The main assembly shop has been built with a very high roof to give room for whole tanks to be lifted over rows of others by means of a twentyton travelling crane. Here the “cruisers” are laid down in parallel rows. The first operation is the assembling of the two sides of the hull. This consists of steel plates to which various fittings have already been riveted. The floor of the tank, a complete unit, then moves forward and the two sides are placed in position. .Axle arms, which carry the bogie wheels with the necessary springs and other components ,are then fitted into place before the outer skin of armour plate is bolted into position. The fitting of these plates calls for a high degree of skill, as the gap between plates must not exceed two thousandths of an inch. This is necessary for the maximum protection of the crew. Each plate before being fitted has been fired at with a two-pounder gun at a distance of thirty yards—a test which leaves only the faintest mark. Gearboxes, engines, tanks, and gun turrets are fitted in quickly succeeding operations, and the tank then passes to the testing ground for a run of six miles, after which it is made ready for a final and much more severe test by inspectors of the Ministry of Supply. LIKE A FANTASY. In the same industrial area as the tank factory I visited is a factory turning cut eighteen different types of army vehicles. This factory has been entirely adapted from the manufacture of commercial vehicles. A small proportion of commercial vehicles is still being produced for export, and at infrequent intervals along the assembly lines I saw civilian trucks among artillery tractors, ambulances and antiaircraft carriers. This is one of the largest factories of its kind in Europe. Its 2,000 mastop day or night. Nine overhead chain conveyors, more than two miles chines and its snail-paced chain-tracks that carry the assembly lines never in length, run through the various workshops and assembly departments. When the conveyors are full they hold 4,000 parts and they can carry a total weight of more than 1,000 tons. To one layman, at least, this network of flying belts, overhead conveyors and tortoise tracks that throw off here a gun tractor and there an ambulance complete with its painted red cross, seemed the nearest thing in real life to a film fantasy of a world gone robot. But the result is real enough —every ten minutes one highly efficient recruit glides out to join Britain’s new mechanised Army.