Secret Weapons (4 page)

Meanwhile, the huge hangars in England where airships were constructed in the 1920s still stand near the university town of Milton Keynes in Buckinghamshire. Today they have a fresh coat of paint. Inside workers are currently busily constructing payload modules, engines and fuel tanks of a revolutionary new airship – the Lockheed Martin Hybrid Air Vehicle. It will be a huge airship over 300ft (91m) in length. Once the British-built hardware has been fitted to the American-made gas envelope, this giant craft will be flown to the East Coast of the United States. There it goes on trial as a surveillance aircraft for the US Military and is destined to cruise at high altitude – up to 20,000ft (6,000m) above areas where soldiers are engaged in warfare, like Afghanistan. There it can remain on station, untouched, unmanned if necessary and watching ceaselessly what goes on beneath. When the last airship left those historic hangars in 1931 nobody would then have guessed that the hangars would be in use 70 years later, this time for the construction of a futuristic generation of airships.

There is one further crucial legacy of airships: the geodesic principle. Conventional aircraft structures were built with straight girders supporting panels. In geodesic designs, the shape of the body is formed from a network of struts. In the post-war years buildings based on this design flourished around the world. The large dome for the Spaceship Earth pavilion at the Epcot Center in Florida is one example; the huge domes at the Eden Project in Cornwall, United Kingdom, are another. Although associated with the name of Buckminster Fuller, the idea was first perfected by the brilliant young British designer Barnes Wallis in the 1930s. After realizing that he could apply this revolutionary design principle to airships, Barnes Wallis turned his attention to the design of a lightweight frame for a World War II bomber. In April 1932 the British Air Ministry placed a contract with the Vickers aircraft company for a biplane with an intimidating list of roles: low-level and dive bombing, reconnaissance, casualty evacuation and torpedo bombing. The result was the Vickers Type 253. The frame of the fuselage was designed by Barnes Wallis, who had risen to become Vickers’s chief structural engineer, and he decided to make it from a geodesic lattice of light-alloy tubes. It was accepted with delight by the Air Ministry. The idea was so successful that Vickers decided privately to build a plane with similar specifications, but in the form of a monoplane. Wallis’s design offered improved performance and an increased payload. This was the Type 246 experimental aircraft and it was so successful in its trials that it became the top-secret Type 287 Wellesley bomber – and was immediately ordered by the Air Ministry under conditions of high security.

During the mid-1930s the Air Ministry in London sensed the approach of war, and realized that the Wellesley bomber would no longer be suitable as a warplane. They commissioned the development of a twin-engined long-range heavy bomber, the Vickers Wellington. It was designed at Brooklands, Surrey, by Vickers’s chief designer, R. K. Pierson, and the fuselage was entirely based on the geodesic design of Barnes Wallis. It was a revolution. Wallis’s design gave one of the lightest yet most robust airframes ever built, and the Wellington thus had a greatly extended range. It was also remarkably resilient. There were many examples of the bombers flying safely back to base, with huge areas of the surface shot or burned away by enemy fire. In one example, Sergeant James Allen Ward won the Victoria Cross for his actions when the wing of his Wellington bomber caught fire. He climbed out of the cockpit, kicking out sections of the fabric covering and using the gaps as footholds, to climb along the wing and manually extinguish the blaze before returning to his cockpit in the howling slipstream and flying safely back to base.

However, there was one problem with the geodesic construction. It required specialized tooling and could not easily be used alongside traditional methods of manufacture. During the war it did not find widespread applications, though it did give the Wellington bomber a unique life-span and a durability that was unparalleled. Was it the best bomber of all? During the entire war, the Mosquito dropped more explosives with fewer losses than any other bomber, and the Lancaster dropped a far greater tonnage. The Wellington’s strong point was its ability to return to base, even if half the fuselage was shot to ribbons. It was the geodesic construction that allowed them to survive. This idea was taken up and popularized by the American architect Richard Buckminster Fuller during the post-war years. Like Wallis, Fuller was not a university graduate; indeed, although he went to Harvard University twice, he was rusticated on both occasions. Nonetheless, his geodesic domes became world-famous and are often described as the world’s first.

Many World War II aircraft were at the opposite end of the spectrum to the airship. Rockets were widely seen as useful aids to the take-off of an aircraft, but what about a plane entirely propelled by rocket power? From the beginning of World War II, the Germans worked on the design of a rocket plane that could outstrip the opposition.

The Nazis conducted their work in such secrecy that the name of the prototype – the Me-163 – was the same as that given to an earlier aircraft, the two-seater Messerschmitt Bf-163 that had been designed in 1938. Every care was taken to ensure that no word of the new rocket-propelled project, code named the
Komet
(Comet), reached the outside world. The first trials were successful, and on 2 October 1941, the Me-163A V4 reached 624.2mph (1,004.5km/h) with Heini Dittmar at the controls. Another Komet pilot, Rudy Opitz, reportedly reached 702mph (1,130km/h) in July 1944, though his account has been doubted by many; in any event, nothing flew as fast again until after the war ended. The Me-163 was named the Komet by its highly innovative designer, Alexander Martin Lippisch. He had earlier envisaged a swept-winged low-powered prototype, the DFS-39, and the Komet further refined his idea. An early proposal was for the aircraft to be propeller-driven, but eventually rocket propulsion was agreed as the way ahead. It was felt that it would give the Luftwaffe a potentially crucial advantage over the Allies.

To conserve weight in flight, the Komet was designed to be launched from a trolley that was jettisoned at take-off. This immediately caused problems, as the wheels often rebounded high into the air and struck the plane itself. The rocket design was modified during tests and was eventually designed to run on hydrazine hydrate and methanol, referred to as C-Stoff, burning in oxygen provided from hydrogen peroxide, T-Stoff (see table below). Hydrazine was in short supply in Germany during the later years of the war and the choice of the same fuel for the V-1 flying bomb led to a conflict of choice. Hydrazine is a dangerous liquid and explosions of the rocket planes while still on the ground were not uncommon. Eventually, protective clothing was supplied to the pilots to resist splashes of the corrosive fuel. The below table lists the liquids used by German rocket and plane designers, some of which were first used in World War I. They were designated as ‘Stoffe’ with code-letters to maintain secrecy and the exact nature of some of the fuels is still disputed.

For the pilot, the launch must have been an interesting experience. Films of a take-off show the aircraft racing along the runway at an alarming rate, oscillating and bumping along the grass, until it climbs from the ground and sheds its wheels, leaving them bumping erratically high into the air. The plane then turns towards the skies and – as if the mechanism has developed a fault – roars upwards at a seemingly impossible speed, climbing at more than 10,000ft (3,000m) per minute. The aircraft itself is not pleasing to the eye, being short and stubby, with projecting rivets and exposed screws. Indeed, the first time I saw one I wondered how it could fly at all; the wing area seemed surprisingly small.

But fly it did. Once aloft, the Me-163B Komet had excellent flying qualities. Lippsich designed the delta wings with leading edge slots which gave it great stability: it was resistant to stalling or spinning. The glider design did pose problems, however, since slight winds could cause the plane to lift into the air unexpectedly when landing and it could fly along in ‘ground effect’ with the pilot finding it difficult to set the plane down where he wished. That apart, the delta design was supremely successful.

At launch, the plane would take off at 200mph (320km/h) and climb gently to an operating speed of 420mph (670km/h) at which point it could climb at some 70 degrees to an altitude of 39,000ft (12,000m) in just 3 minutes. The Komet could then accelerate to a final operating velocity of 596mph (959km/h) or even faster, so that it was higher, faster and more manoeuvrable than any conventional aircraft. Nothing could touch it.

In practice, the speed and agility made the Komet into a difficult machine of war. Its velocity and rate of climb meant that it reached – and passed – its would-be target in a matter of seconds. The rapid flight of the Komet meant that the pilot could hardly ever hit a slow-moving bomber. One highly ingenious answer to this was developed, the Sondergerät 500 Jägerfaust. This secret weapon was a group of five upward-pointing guns firing 2in (50mm) ammunition that was installed in each wing. They were triggered automatically – the firing mechanism was in fact actuated by a photo-electric cell. All the pilot had to do was fly beneath the intended target, and the shadow cast by the plane on the Komet would cause the guns to fire automatically, with guns pointing upwards into the belly of the target plane. It was an ingenious idea. Even so, only one aircraft was shot down by this system. But most standard Me- 163s were instead fitted with two 30mm (1.18in) MARK-108 cannon, a design which was subsequently manufactured widely in Germany and beyond.

The greatest problem with the Komet was the short flight time. The maximum burn of the rocket motor was only 7½ minutes which meant that the plane might seem to be a highly intimidating interceptor fighter – but could, in reality, do little damage to the enemy. Modifications were made to the engines, to give the pilot two separate rocket motors – a high-powered rocket to blast him up to operating altitude, and a smaller, less powerful rocket motor to maintain his cruising speed. These later models were to have a pressurized cockpit to protect the pilot and the maximum altitude was to be increased to 52,000ft (15,800m) which would give a powered flight time of up to 12 minutes. However, these improved models remained untested by the end of the war.

The Komet did not enter active service until 1944, and its psychological impact on the Allies was considerable. Its effect in terms of attack success was much more limited. The usual attack pattern was for the pilot to fly through the Allied bombers at high speed, reach an altitude of 35,000–39,000ft (10,000–12,000m) and then dive down to the bomber formation once more. The Komet pilot thus had just two brief opportunities to shoot at the enemy. Since he was usually in an unpressurized cockpit the pilot was fitted with a restrictive oxygen mask and, with the protective clothing, was unable to respond rapidly. In spite of all the development and the meticulous design, this aircraft was a tactical failure and many of the Komets were grounded owing to a shortage of fuel. There were 16 confirmed examples of bombers shot down by a Komet. The most successful pilot, Feldwebel Siegfried Schubert, had just three successes to his credit.

Nonetheless, the Komet rocket plane was a truly innovative design and it pointed to what lay ahead. The production version was 18ft 8in (5.7m) long, had a wingspan of 30ft 7in (9.33m) and was 9ft (2.75m) tall. Its weight was 4,200lb (1,905kg) when empty and 8,710lb (3,950kg) when fully loaded, and it had an operating range of about 25 miles (40km). Even now, designs derived from these tiny aircraft still operate. Planes like the Skybaby are popular with hobbyists – it is 5ft (1.52m) tall with a wingspan of just 7ft 2in (2.18m) and a top speed of 185mph (298km/h). The Bumble Bee II designed by Robert Starr is 8ft 10in (2.7m) long, has a wingspan of 5ft 6in (1.67m), weighs 396lb (180kg) and has a top speed of 190mph (306km/h). It seems that the little plane projects of World War II have inspired many imitators since.