Fritz Lang, the director of ‘Frau im Mond’ and also of the futuristic ‘Metropolis’, was invited by Dr Goebbels, the national socialist propaganda chief, to co-operate in the presentation of national socialism to the nation and to the world. Lang, an honourably wounded ex-soldier in the Austrian army, fled to America the next day. He was half Jewish.
Research continued apace under the army’s auspices. But the problems of liquid fuel rocketry were great. Liquid oxygen itself boils at – 183 degrees centigrade, and therefore problems occur with freezing pipes and valves. It explodes on contact with organic chemicals, including grease. But when in combustion, it melts metal. A liquid fuel rocket cannot be rotated for accuracy like a shell, because of the centrifugal forces on the fuel tanks and pipes.13 These problems were gradually solved; ‘regenerative cooling’ exchanged the heat of combustion with the cold of the liquid fuel; the temperature of combustion was controlled by the use of alcohol (with which water can be mixed) as the oxidiser and a film of alcohol fuel on the walls of the combustion chamber and nozzle14; fuel feed problems were solved by the use of an immensely powerful turbopump powered by steam generated by hydrogen peroxide and a catalyst, calcium permanganate.
In December 1934 the first two A2 rockets, with 300Kg thrust engines, were successfully launched. A political alliance with the powerful new national socialist Luftwaffe, headed by Reichsfuhrer Hermann Goering, was instituted in 1935. The Luftwaffe were interested mainly in rocket assisted take off for conventional aircraft, a pulse jet ‘cruise missile’ and a rocket aeroplane at the time. Resulting from the pulse jet cruise missile experiments was the FZG 76 (V1) flyingbomb, and from the rocket plane idea the Messerschmitt ME163B ‘Komet’, powered by a mixture of hydrogen peroxide with hydrazine-hydrate in methanol. These different weapons and fuels were later to complicate the intelligence picture in Britain.
Walter Dornberger and the rocket team felt that a new experimental site was needed; ‘we wanted to build, and to build on a grand scale’, he wrote.l5 In order to extract extra funds from his superiors, he invited them to a demonstration of his wares. In a world used to biplanes and steam engines, the vast power, the noise, the spectacular flaming rocket motors would subvert the hardest and most practical of men.
In March 1936 General Baron Wernher Von Fritsch (1880-1939), the Commander in Chief of the German Army, was persuaded to visit Kummersdorf. There he was subjected to a treatment to which many high ranking Germans would succumb. He was introduced to rocketry by lectures illustrated with coloured drawings and diagrams, and then exposed, successively, to test bed demonstrations of 650lbs, 2200lbs and 3500lbs thrust engines. To the 56 year old ex-staff officer, whose early years had not seen powered flight, it was an experience of impressive and seductive grandeur. ‘Hardly had the echo of the motors died away in the pine woods, than the General assured us of his full support’, wrote Dornberger.16 But there was a proviso – the rocket had to become a specific, defined weapon. Fritsch asked them how much they wanted. They asked for, and obtained, a complete armament programme and, in conjunction with the Luftwaffe, a dedicated site.
They found this at Peenemunde, on the Baltic coast. The site was immediately purchased for 750,000 marks. Dornberger met with Riedel and Von Braun to discuss the weapon that they needed in order to justify this princely sum. Becker had already felt, during the war, that rockets – even the crude devices available at the time – would be a better means of delivering poison gas than the projectors then in use. But they should now use long-range, precision rockets, designed in the first place for gas bombardment, and to provide a long-range alternative to bombing with high explosive.17
Both Von Braun and Riedel considered that a really big rocket was required. Dornberger agreed, with a proviso concerning ease of transportation. It was therefore decided that the rocket should be capable of being carried on existing roads and railways, and launched using simple and mobile equipment. Within these limits, a range of 160 miles (twice that of the Paris Gun) and an explosive (or chemical) warhead weight of one ton (100 times greater than the gun) seemed attainable. The thrust required for this would be 25 tons.
The accuracy of the new weapon was to be from 2 to 3 mils, that is, for every 1000 metres travelled it would be only 2 or 3 metres off target, both in range and line. At the extreme range of 160 miles it would fall in a circle of around 650 metres radius.
By first World War standards, therefore, the proposed weapon was formidable indeed – but it was also hugely expensive. In the Great War it would have enabled Germany to reach out to hit enemy Headquarters, ammunition dumps, supply depots, railway yards and junctions with sudden, unstoppable and devastating effect. The firing crews would be too far behind the lines to be hit by counter battery fire, but it could not be used as prodigally as artillery shells; in the last two weeks of August 1918, the much smaller British army expended some 6 million shells. It had rarely used less than a million shells a week since 1917.18
Heavy artillery, however, was always closely connected with air power. The gunners could not see their target – did not even know if a target was there. Aerial photography and spotting were essentials of the ‘deep battle’,19 and the rocket without air power would be useful only to attack immovably fixed targets, i.e. cities, if it were to be used against an enemy who possessed command of the air.
Perhaps another limitation of the artillery rocket was that, if you devastated a rear area in the course and for the purpose of an offensive, you had to reach it fairly quickly during your advance in order to take full advantage of the damage, disorganisation and effect on enemy morale. But rapid advances of 50 to 150 miles were not usual on the western front in the first World War. This meant that its effect would, in those circumstances, be more attritional or strategic than tactical; and although it was always gratifying to kick your enemy without his being able to reply, it would have been an expensive method of achieving it, akin to the ‘breaking windows with guineas’ by which British operations in the early part of the Napoleonic war were characterised.
How many such rockets would be necessary to achieve general ‘devastation’, or to be certain of hitting a target? Bombardment to destroy a whole area is expensive in shells, due to the phenomenon of ‘overhitting’, i.e. from the first shell onwards, you become more and more likely to hit an area already hit; by the time, for example, 50% of the area is damaged, half of all your shells will be ‘wasted’ in this way. In 1944 scientists calculated that to achieve a 50% devastation of an area of one square mile, with a 600 yard aiming error, 250 tons of bombs would be required. But to achieve an increase of 30% to an 80% devastation, would require 600 tons, nearly two and a half times as much.20 It so happens that the planned accuracy of the rocket at 160 miles, and the 1 ton warhead, means that ‘tons’ may be read as rockets. This was thus an expensive way to devastate a target. If the aiming error were to increase to 2000 yards, then to 50% devastate the area would require 1250 rockets, and to 80% devastate, 2900.
A War Office investigation was carried out in order to ascertain how many shells would be needed to be almost certain to destroy a particular target, and a paper21 on the mathematics of bombardment was published some time later. In the paper, six terrorists are presumed to be in a forest of an area of 4 square miles, the question being, how many shells are required to place one shell within 10 yards of one terrorist? The paper concluded that a 1 in 20 chance requires 340 shells, a one in 10 chance needs 690, an even chance requires 5560 and a 95% chance 74,000 shells. Artillery bombardment is an expensive business, and it may be thought that, even with the accuracy specified, a 46 foot, 13 ton rocket, needing 9 tons of fuel to blast
