Context

The detonation in 1945 of atomic bombs over the Japanese cities of Hiroshima and Nagasaki set in train a rapid arms race. Within a decade of those first strikes, thermonuclear devices, with faster and longer-range delivery systems, were capable of yields more than 1,000 times more powerful than those used over Japan.

Over that decade, the British state had conducted studies into the effect of nuclear explosions. Detonation would trigger an intense burst of light and heat, followed by a powerful shockwave, which would devastate and irradiate a localised area and destroy electrical services through an electromagnetic pulse. That first shock would be followed by airborne radioactive dust, able to travel on prevailing winds to endanger areas many hundreds of miles from ground zero.

The York Headquarters

20 Group Control was constructed on government ground on the western side of York, accessible to the urban centres of both York and Leeds. Tucked away behind a Victorian villa, its existence was an open secret throughout its operational life. The semi-sunken, mass concrete structure was not designed to withstand a direct hit. Instead the UKWMO system relied on a concept of redundancy – that roles, equipment and data were replicated across many sites and could be picked up if another site went down.

Each post and control had the same basic equipment for observing a bomb’s orientation, power and subsequent radiation levels. At the heart of the control, an operations room – its design taken from ops rooms of the previous war – recorded data across a series of charts, maps and forms, then transmitted this information by teleprinter to clients.

Maintaining communications was crucial to the system working, and while much of UKWMO equipment changed little over 30 years, the communication technology developed over time. By time of stand down, the ROC were using Victorian pinhole camera technology to spot bombs, and a Message Switch Exchange (which can be understood as a precursor to the internet) to inform the world.

The ROC

The ROC was a diverse organisation for its time. With a roughly equal gender spread, its role in urban and rural locations, and across differing socio-economic areas, saw it recruit from a wide social pool. The corps retained a close affiliation with the RAF, despite having moved into the Home Office, reflected in its uniform, insignia and hierarchy of roles.

Membership demanded the commitment of time, adherence to discipline and, ultimately, a willingness to sacrifice your personal affairs to the national cause. It also brought a fraternal bond formed through a strong sense of identity and affiliation. Despite, or perhaps because of, the gravity of its purpose, the ROC was also an intensely social organisation. Lifetime friendships and relationships were born from the corps – and a pride and sense of association are still keenly felt and fostered by its veterans.