The British Imperial Airship Scheme
Created | Updated Nov 8, 2013
After the Great War, the airship was a developing method of air transport. It continued where Count Zeppelin left off in 1914. Unlike aeroplanes, the airship could offer ocean-liner comfort without sea sickness and it could also arrive earlier. Over land, no train could compare to the luxury and stability of airship travel.
Aeroplanes did begin to develop at the same time, but they were small, smelly, uncomfortable, noisy and, in some cases, extremely draughty. In the 1920s, they were not a serious contender to carry passengers on medium- or long-distance flight. The airship had much to offer. The technology was developing, but it was already quite advanced in the years immediately after the 'War to End all Wars' (WWI). Indeed, the British airship seemed to go on where Zeppelin had left off. The origins of the airship race lay further back in time, when they were considered a weapon of war.
The Early Design Record
Short Brothers had an airship manufacturing establishment at Cardington, near Bedford. In 1919, they were given a contract to develop a British version of the Zeppelin 'Height-climber', a high-speed, high-altitude airship. The project was 'Nationalised' later the same year and Cardington became the Royal Airship Works. Work progressed slowly, but was hampered by changes in policy. The project was eventually sold to the USA.
At last, in June 1921, R38, the world's largest airship, took to the air to move to Howden, Yorkshire. There, she was to be flight-tested before hand-over to the USA and she was put through a series of flight trials. On 24 August, on a trial flight over the Humber, she was put into a tight turn. The ship crumpled in the middle, the front section broke away and ignited, killing all 44 crew in that section. The five crew members in the tail section escaped as it fell into the waters of the Humber.
The official investigation gave the cause as structural weakness, with no technical explanation. The manoeuvre was too much for the airframe and there is a suggestion that the design team did not attempt to calculate the effect of aerodynamic forces on the structure. Despite this, no one on the government design team was removed or disciplined.
Vickers were builders of British dirigibles or rigid airships, like the German Zeppelin. The construction of the R80 began in November 1917. The design was to follow that of the Zahn shape, similar to the Zeppelin, being a tube with streamlined ends. The designers, Barnes Wallis and HB Pratt, had a number of successes under their belts, but Barnes Wallis was not convinced that the design was all it could be. They had been forced to make this a smaller vehicle than they had wanted to, as there were no large sheds available. Wallis decided to reshape the envelope of the airship and came up with a constantly curving outline, a true streamlining of the airship. This gave it only 3% resistance, against some 40% for the Zeppelin, meaning that only 3% of the power for forward motion was taken up in getting it moving. It first flew in 1921, delayed by the lack of funding and momentum by the end of the war. It was redirected from military use to civil use, losing government funding in the process. It was recognised as a good design but was dismantled in 1925 after being used for destructive tests on components. There seemed to be no market for such aircraft. The R80 had a total weight of 38.3 tons (38.9 tonnes) yet a disposable lift1 of 14.9 tons (15.1 tonnes).
In 1924, as part of the Imperial Airship Scheme, it was decided to establish an air route to India. Usage of aeroplanes was not considered and the example of the German airship route to South America was followed. There would be two airships designed and built, one by private contractors, the R100, and one by the government's Royal Airship Works at Cardington, the R101. The Government team was the same one that had designed the R38 and had all the data the government agencies could provide. A subsidiary of Vickers, the Airship Guarantee Company, was awarded the private contract and the R100 was built at Howden in Yorkshire. Barnes Wallis led the design team.
For some reason, there was an element of competition here, with the government ship in the forefront. The Labour government may have been trying to prove the superiority of their philosophies over the established system - it certainly seemed that way. The project survived through two changes in government but there were, once again, changes in policy and priority. Although the R101 team knew all about the R100, the reverse was quite different. Vickers did their own wind tunnel and structure tests and sent the results to a central aerodynamics data office. They got most of their information about the R101 from the newspapers.
The first to fly was the R101 in October 1929. It was streamlined using the principles of the R80 and there was no limit to the expense on development and experimentation. There was, perhaps, too much innovation as development costs rose due to underdeveloped technology. Every item was designed and redesigned for the project rather than being bought from existing sources. Petrol engines were then thought to be unsuitable for use in the Tropics so R101 was powered by diesel engines, which proved troublesome. On completion, the ship was the largest manmade object ever to fly. Despite all this innovation, it was found that the disposable lift was not as great as had been envisaged, being only 35 tons (36 tonnes). To rectify this, it was cut in two and lengthened to provide more gas cells and, hence, more lift. On its next flight, a rip developed in the envelope and the resulting control difficulties nearly ended in disaster.
Much was left untested or overlooked. There was no 'second look' by an independent design team to identify potential problems. This was usually performed as it was recognised that designers are often less likely to note faults in their 'baby'. One example of this was the use of a rubberised compound and dope2. The combination corroded the fabric envelope on the airframe. This fact could have been provided by the manufacturers of either product, but it was not noted or asked for. After the troubles with the original design, time was of the essence and a great effort was made to make an early maiden flight. Many detail changes were left undone.
The Vickers team had to work to a strict budget and innovation in construction was limited. The R100's first flight was in December 1929. It was the first use of Barnes Wallis' geodetic framework, which was light and strong. It proved itself able of 81 miles per hour (130 kilometres per hour), and produced a lift of 57 tons (58 tonnes). Unlike the R101, it was given a 'second look' without major rework. To cut costs, it used petrol engines, which were reliable. After trial flights, it was to take the less important maiden voyage to Canada.
R100 left Cardington on 29 July, 1930. The ship flew over the Atlantic and headed down the Newfoundland coast to Montreal. It arrived on 1 August, after a voyage of some 78 hours 49 minutes, and 3364 miles (5410 kilometres). Some damage was sustained by the envelope during the last part of the crossing, but it arrived safely and the damage was repaired without difficulty. After some local tours in Canada, R100 started for home on 13 August, 1930 arriving on 16 August, 1930, after 2995 miles (3690 kilometres) and 57 hours 56 minutes. 21 hours were gained using the wind system that follows the Gulf Stream.
The End of Airship Usage
After this success, the R101 needed another flight to prove it the better airship. It was to fly to India, leaving England for Karachi on 4 October, 1930, and returning by 18 October, 1930. Lord Thomson, the then Secretary of State for Air, would be one of the passengers. On the evening of 4 October, 1930, the R101 lifted off in bad weather, which soon became worse. Battling against a headwind, she wallowed for seven-and-a-half hours and flew only 220 miles (350 kilometres). Passing over the French coast, her height was estimated at just 300 feet (90 metres). The reason why this happened is unclear, but the pressure of the headwind may have affected the R101's altimeter, giving a false reading.
She was over Beauvais, when she started a steep dive, pulled up, dived again and hit the ground. She bounced, but then fell a second time, breaking at the point where the lengthening had been added. Sparks from a severed electrical cable were thought to have ignited the hydrogen, which destroyed her completely. All the passengers who were in their cabins were killed; only six crew members survived out of the 54 carried. The official report blamed the collapse of the forward gasbag, which was caused by a failure in the fabric covering of the envelope nose. Could this have been one of the areas treated with rubberised compound? It has never been confirmed. This may have been because most of the design team were on the R101 as passengers and died with her.
Whatever the reason, the disaster effectively ended Britain's airship development. The passengers on the R101 were the champions of the Imperial Airship Scheme and it died with them. The R100, the success story of the venture, was overshadowed by the R101 disaster. She was returned to the shed, deflated and stored. When the scheme collapsed, there was no use for the R100 and she was sold for scrap, bringing just £450. Dismantling began in November 1931 and was completed in February 1932.
Barnes Wallis developed his geodetic design into aeroplane structures and went on the design the Wellington Bomber. Later, during the Second World War, he designed the famous 'bouncing bomb', used by the 'Dambusters' (617 Sqadron RAF), and the 12,000lb (5400 kg) 'Tallboy' bomb. After the war, he developed the first practical swing-wing designs.
Slide Rule by Nevil Shute. Nevil Shute Norway was the Chief Calculator on the R100 design team. The 'Calculators' did the job now performed by computers, checking on component dimensions and materials for the designers. Slide Rule is his autobiography.
- Pathe film footage showing R100 landing in Canada in 1930
- R101 Disaster