R101 - Background

Background

R101 was the result of a British government initiative to develop airships to provide passenger and mail transport from Britain to the most distant parts of the British Empire, including India, Australia and Canada. These distances were too great for heavier-than-air aircraft of the period. The Burney Scheme of 1922 had proposed a civil airship development programme to be carried out by a specially established subsidiary of Vickers with the support of the British government, but when the General Election of 1923 brought Ramsay MacDonald’s Labour administration to power the new Air Minister, Lord Thomson, formulated the Imperial Airship Scheme in its place. This called for the building of two experimental airships: one, R101, to be designed and constructed under direction of the Air Ministry, and the other, R100, to be built by Vickers's Airship Guarantee Company under a fixed price contract. This led to the nicknames the "Socialist Airship" and the "Capitalist Airship".

In addition to the building of the two airships, the scheme involved the establishment of the necessary infrastructure for airship operations; for example, the mooring masts used at Cardington, Ismailia, Karachi and Montreal had to be designed and built and the meteorological forecasting network extended and improved.

Specifications for the airships were drawn up by an Air Ministry committee whose members included Squadron Leader Reginald Colmore and Lieutenant-Colonel Vincent Richmond, both of whom had extensive experience with airships, principally nonrigid ones. These called for airships of not less than five million cubic feet (140,000 m³) capacity and a fixed structural weight not to exceed 90 tons, giving a "disposable lift" of nearly 62 tons. With the necessary allowance of about 20 tons for the service load consisting of a crew of approximately 40, stores, and water ballast this meant a possible fuel and passenger load of 42 tons. Accommodation for 100 passengers and tankage for 57 hours' flight was to be provided and a sustainable cruise speed of 63 mph (101 km/h) and maximum speed of 70 mph (110 km/h) was called for. In wartime, the airships would be expected to carry 200 troops or possibly five parasite fighter aircraft.

Vickers's design team was led by Barnes Wallis, who had extensive experience of rigid airship design and later became famous for the bouncing bomb. His principal assistant (the "Chief Calculator"), Nevil Shute Norway, later well known as a novelist, gives his account of the design and construction of the two airships in his autobiography, Slide Rule: Autobiography of an Engineer, which was first published in 1954. Shute's book characterises R100 as a pragmatic and conservative design, and R101 as extravagant and over-ambitious, but one purpose of having two design teams was to test different approaches, with R101 deliberately intended to extend the limits of existing technology. Shute later admitted that many of his criticisms of the R101 team were unjustified.

An extremely optimistic timetable was drawn up, with construction of the government-built airship to be begun in July 1925 and complete by the following July, with a trial flight to India being planned for January 1927. In actuality, the extensive experimentation that was carried out delayed the actual start of production of R101 until early 1927. R100 was also delayed, and neither flew until late 1929.