Sample - WW1 Buildings: Medium Span Aeroplane Sheds 43-44/17 & 164-165/17

Below is a sample of part of one of our 'Historic Records' that are accessible within the ARG Members Area. These small reports are intended to cover the majority of airfield buildings, divided into First World War, Interwar, Second World War and Cold War categories. This is the result of many years of research by ARG members and are illustrated with contemporary and recent photographs as well as maps and drawings based on preserved material within the archive.

First World War Buildings: Medium Span Aeroplane Sheds 43-44/17 & 164-165/17

The earliest designs of Belfast trusses of Mc Tear & Co Ltd. (from 1866) differed from those used on aeroplane sheds in that the lattice bracing between the bowed upper chord member and the lower tie-beam was arranged as two interlocking fans. The angle of the lattice bars represented setting-out lines (in degrees) worked out from a point where both wall post (at either end of the truss) met the floor to a point on the curved bow.

The Anderson Belfast Lattice Girder

The D Anderson & Son Ltd Rok Roofing Belfast lattice girders were advertised in 1915 in the aviation journal ‘Flight’ as being cheap, light, and strong, minimises fire risk, gives an equable temperature, is absolutely weather proof and can be built in 100ft spans.

The Anderson truss consisted of a curved laminated upper chord and laminated tie-beam with close mesh lattice bars in a parallel criss-cross pattern between the two members. The curved bow was made up of four individual sections of two, 3in square rib sections sandwiched either side of the lattice bars. The ends of the bow are anchored to the tie-beam by knee braces and gusset boards which secures the truss to laminated timber wall posts and angled bracing struts (of the earlier sheds), or brick buttresses of the later sheds. The trusses are externally clad with tongued-and-grooved boarding fixed diagonally and covered with bitumen felt .

This form of roof construction was adopted for large-span buildings such as, aeroplane sheds, large stores, salvage sheds and running sheds.

RFC General Service Aeroplane Sheds

As early as 1914, the firm of D Anderson & Son Ltd. had been supplying their Rok Roofing with Belfast lattice girders for the construction of aeroplane sheds at Calshot (Listed Grade 2*) and Hamble Point. In October - November 1916, single-span timber-framed RFC general service (GS) sheds with this form of roof construction were being erected at Harlaxton and South Calton, Lincs.

Although a coupled shed with Belfast lattice girders had been built at Hamble Point as early as 1914, it was not until after 1917 with the construction of the sheds at Hendon, that coupled GS sheds became the universal practice for shed roofs on RFC aerodromes. The layout of the new RFC Training Depot Stations under construction towards the end of 1917 changed from the previous practice of having six single span sheds (as at Harlaxton) to having three pairs of coupled sheds and one single span shed for aeroplane repair (as at Hendon).

In order to erect the coupled sheds (after Hendon) a change in design took place whereby timber-framed walls gave way to brick construction. The number of bays was reduced from 17 to 16 but to keep the overall length to similar dimensions as before, the roof girders were arranged at 10ft 6in centres. Brick buttresses supported the roof girders with temporary brick wall infilling. Similar steel-framed window frames were used but were horizontal frames instead of vertical types. Brick was also used instead of timber for the door gantries which now took the form of six brick piers supporting two, 20ft high large-radius arches either side of the door runners. The doors remained timber-framed but were now clad with flat asbestos sheeting. Coupled and triple-span sheds had brick arches in-lieu of walls running longitudinally and these supported the ends of the roof girders of either sides forming the multi-span shed. At Hendon the central columns are timber and this arrangement pre-dates all brick versions.

RFC Training Depot single-span ARS sheds had two, 32ft wide side annexes built against a side-wall. These were plane stores for the storage of aeroplane wings and fuselages. Each one had its own pitched roof incorporating composite timber trusses. The workshop annexe on the opposite side-wall (facing the aerodrome) contained a boiler room, instrument and camera workshop, inspector and NCO’s room, Commanding Officer’s office and general office .

Summary

Doors: timber-framed and clad doors in six leaves, open out into timber-framed door gantries supported by timber trestles, while the later buildings had brick-built gantries.
Walls: timber framed with corrugated iron sheeting. Later buildings were temporary brick with external buttresses.Annexe: one annexe was provided along a side wall containing a heating chamber, stores and dressing room.
Glazing: two metal casement type windows in each bay except the end bays. Coupled sheds had ridge-mouten lantern lights.
Roof: ROK roofing with tongue and grooved boarding covered in felt.
Dimensions: clear span 80ft by 170ft 9in and clear height 20ft.


An early shed under construction at South Carlton


Flight shed at Lympne


ARS shed at Harling Road


Coupled shed at Henlow



For the complete version please see the ARGL Historic Lists in the members area