With the Taylor report being regarded as the standing instruction for airfield defence in 1940, the Air Ministry issued some basic principles for pillbox construction and siting:
Pillboxes should only be large enough for the garrison to man their weapons. Sleeping accommodation should be separately provided.
They should have the minimum projection above ground level necessary for an adequate field of fire.
Wherever possible, natural concealment should be aimed at. It may sometimes be necessary to use two pillboxes instead of one but this was justified by the reduced vulnerability to air attack to both pillboxes.
Pillboxes covering the perimeter should be sited to fire along the wire on both sides of them.
Pillboxes sited to cover the landing ground should be mutually supporting.
A variety of designs of pillboxes were used in airfield defence but Types 22 and 23 were the most common.
The defence of an airfield was to be controlled from a post situated to provide a good view over the aerodrome and its surroundings. At first this was usually in buildings such as the Watch Tower but by 1941 a purpose Battle HQ design was issued by the Air Ministry which had an underground chamber and a cupola with an all round narrow observation slit.
The Taylor report specified the operational need for a miniature fort that could be sited on the landing ground on an aerodrome without interfering with its use- the “Disappearing Small Arms Turret”. The rationale behind this was that aerodromes provided a wide field of fire and that a fort situated in its centre may hold up the capture of the aerodrome for a long period.
The fort would have to meet the following specifications:
It must be able to hold out against airborne troops and weapons for a long period. Hence it would have to be proof against 20mm Armour-piercing SAA rounds and have overhead protection from hand grenades and against SAA from the air.
It should be capable of housing a minimum of two light machine guns as it would have to be able to defend against simultaneous attacks from the front and rear.
It should be able to hold out for a minimum of 48 hours so sufficient storage space would be required for food, water, ammunition etc.
When raised, the turret should have all round observation and when closed observation should be possible through a periscope.
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.