Group of three Fighter Dispersal Pens at Biggin Hill Airport

Three fighter dispersal pens were built around 1939 as early type E structures at Biggin Hill Airport. Two of the pens have been altered after the Second World War. The structures are built of brick and concrete, largely covered with earth banks. The air raid shelters are constructed of pre-cast concrete. The pens are situated on the south-eastern edge of the airport, arranged in a row running north-south and opening westward onto the perimeter track. Each pen originally had an E-plan layout, divided into two 15-metre wide bays separated by a central traverse, with concrete hard standings. An air raid shelter for the ground crew is located at the rear of each pen, accessible from both bays and the rear of the pen itself.

The southern pen is the most complete, retaining the earth-covered central traverse, which features a concrete spine wall. The earth-covered outer traverses have brick spine walls with concrete dwarf retaining walls. The ends of the outer traverses have truncated, triangular-shaped brick retaining walls. The air raid shelter has mass concrete entrances and passages, reinforced concrete roofs, and corrugated metal lining inside, with the original inner steel blast doors remaining (although the outer doors have been lost). Fixing rings for securing aircraft remain on the concrete hard standings within the bays.

The central pen has lost the projecting traverses, except for a section of concrete dwarf retaining wall on the inner edge of the northern traverse. Part of the rear earth banking has also been lost. The air raid shelter survives and is generally similar to the southern pen, with inner blast doors (one marked “PETROLEUM/SPIRIT/NO SMOKING”, indicative of later storage use) and exposed concrete walling in the northern entrance passage. Some fixing rings remain on the surviving southern section of the hard standing.

The northern pen has lost its central traverse, and the earth-covered northern traverse is partly denuded. The air raid shelter retains its inner blast doors and corrugated lining. Fixing rings are also visible on the hard standing.