Portable Airship Hangar (Formerly Buildings R51 And Q65)

Portable Airship Hangar

This portable airship shed was built in 1912 at Farnborough, designed and constructed to test a mobile base concept for military airships. The frame was reassembled at its current location on Pinehurst Road in 2004.

Materials and Construction

The shed is constructed of a lattice steel frame with members riveted together with steel pins and stabilised with steel wire ropes. The structure is aligned east-west and comprises fourteen trusses, each made up of eight frame members bolted together. Each frame member consists of a box section formed from riveted angles and flats, bolted to create a curved or approximate catenary arch rising from the ground. Of the original 112 lattice steel frame members, 108 have been reused; four replacement members are present on the two eastern end trusses. Steel purlins join the adjacent trusses along the arch pinnacle and at three points down each truss side. A network of steel wire ropes attached to the ground provides stability, with attachments at each point where the purlins meet the frame members. Only two trusses were replaced; the remainder are original, though some rivets have been renewed. The structure has been hot zinc sprayed for protection and given a five-stage paint process. The top has been treated against damp pooling and spiked to prevent birds from alighting, with a mesh anti-climbing screen planned. Lightening conductor straps are attached to the frame.

Subsidiary Features

Each truss sits on a reinforced concrete plinth with cement and pebble dash cladding, raised 0.55 metres above the floor on piles.

Historical Development

Balloons were used as observation platforms during the Napoleonic Wars and American Civil War. In 1879 the Royal Engineers formed a Balloon Equipment Store at Woolwich Arsenal, moving it to the School of Military Engineering at Chatham in 1882. The Balloon School transferred to Linsing near Chatham in 1886, relocated to South Farnborough in 1890, and moved to its final site at South Farnborough in 1905 when the Balloon Factory merged operational and training units. Several permanent dirigible sheds were subsequently constructed at Farnborough: shed 'B' in 1906 (demolished 1965), shed 'A' completed in June 1910, and shed 'C', for which £28,000 was allocated in October 1910 and which was erected from 1912 onwards. Both sheds 'A' and 'C' were later moved to Kingsnorth and demolished around 1930.

In early 1912, the army began testing portable sheds to allow airships with their supplementary equipment to be deployed operationally as required. This portable shed was constructed at Farnborough in March 1912 at a cost of £850, designed to accommodate a similar range of airships to sheds 'A', 'B', and 'C' (namely Gamma, Eta, Beta, and possibly Delta). Aldershot Chief Engineer G. Scott-Moncrieff suggested the shed be moved to the Central Flying School at Upavon for testing, as space at Farnborough was limited due to concurrent RAF and RFC shed construction. The canvas underwent repair until June 1912. A potential test site was identified at Tidworth Pennings, Wiltshire in October 1913, but all action regarding accommodation for the airship squadron ceased at the end of October and the project is believed to have been abandoned. The portable shed was dismantled and stored after October 1913.

Rather than being re-erected in Wiltshire or at the RAF Farnborough site, the shed was divided into two parts and incorporated into separate factory buildings at Farnborough. The lower part of the frame became building Q65 (the fabric workshop), erected in 1916–17, and the upper part became building R51 (the forge and foundry), erected in 1914.

At the outbreak of the First World War, Britain possessed very few rigid airships (those with a hull framework) and non-rigid airships, and only six airship sheds. The threat posed by German submarines prompted the Government to address this deficiency. By the war's end, 61 airship sheds had been constructed. Only three others, apart from this portable shed at Farnborough, have been identified and designated: the roof of a former airship shed relocated to Moat Farm, St Mary Hoo, Kent (Grade II), and sheds No.1 and No.2 at Cardington, built in 1916–17 and 1928 respectively (both Grade II*). The Cardington sheds are the only in situ examples, ranking globally alongside Ecausseville (1918) in France and inter-war examples in the United States. The 'Y' hangar at Chalais Meudon, north of Paris, erected in 1879 from a shed built the previous year for the Paris Exhibition, is the earliest surviving airship hangar in the world.

Farnborough is one of the world's key sites for aviation development, demonstrating the close involvement of state governments in supporting aviation technology and its military application. Its closest comparable site in a European context is Chalais Meudon in France, where various buildings including the 1879 airship hangar and wind tunnels survive, and the Adlershof research and development centre at Johannisthal, east of Berlin. The survival of airship sheds at Farnborough and Cardington is particularly significant and rare in a European context, notably given the absence of surviving examples in Germany, which led in this technology.