Above: The "Disappearing Small Arms Turret"
As a much cheaper and easier to construct alternative, the “Champagne” style dug-out was suggested. This was basically a slit trench dug-out with a ramp or other device allowing a Vickers machine gun to be run up above ground. It could easily be fitted with a roof or flap to allow an aircraft to run over it. It was not thought that this would fore fill the same role as the “Disappearing Small Arms Turret” as it provided little cover for the Vickers gun crew once the gun had been run up above ground.
Eastern Command considered that such a disappearing pillbox could be of use if the ground was dead flat but would be useless on aerodromes with ridges. South Eastern Command considered they were tactically unsound as the isolating of two men was in direct contrast to the accepted principal of defended localities. Southern Command considered they would be useless either on airfields which would have to be used by our own aircraft up to the last minute or in the event of a surprise attack as it was unlikely the crew could get to the pillbox in time in both cases. London District considered them of value against dive bombers. In general the London District was in favour of them on their aerodromes but Eastern, South Eastern, Southern and Northern Commands were not in favour of them.
Despite these reservations, the pillbox was sited on over 50 aerodromes throughout the country, including Ipswich, Martlesham Heath and Wattisham in Suffolk.
By June 1941, it was considered that defences on aerodromes should consist primarily of field works. However it was thought that in certain situations pillboxes would be desirable. G.H.Q issued two standardised pillboxes for airfield defence (a rectangular type and a pentagonal type). The walls of both types were to be 3’6” thick to withstand bursts from an 8cm anti-tank gun, the roof 1’6” thick to be proof against 20mm armour-piercing rounds. Loopholes fitted with Turnbull mounts were to be limited to two and living accommodation was to be provided for two men with fitted bunks.
Right - the pentagonal type of pillbox, based on
an existing design but with thicker walls and roof.
The Commands were instructed to indicate if there was sufficient call for either design on their airfields. Eastern Command replied that it was not in favour of constructing more pillboxes on airfields and had already ordered a halt to the construction of any new pillboxes.
By the spring of 1942, just as with beach defence, pillboxes were no longer considered suitable for aerodrome defence. Following the experience in Crete, it was felt that the pillboxes and breastworks constructed as a result of the Taylor Report were large and conspicuous and extremely vulnerable to aerial attack. Small and inconspicuous defences were now required. In Eastern Command, the defences of RAF Hethel Station were organised by constructing small two man weapon-pits and small machine gun pits in accordance with “ Infantry Training 1937” – Supplement No 3 “The Design and Layout of Field Defences” and at least two aerodromes, West Raynham and Great Massingham, defences were reorganised in line with the change in policy.