We have long been familiar with reports of German underground airplane factories where the Nazis sought not merely concealment but safety from bombing raids, and where an uninterrupted flow of production might be maintained.
Word has now reached us concerning similar British factories which have been located in chalk mines and quarries. Full Ministry cooperation is said to have been given to converting disused underground works into factories for aircraft production. As in our "blackout" buildings air conditioning plants are installed and fluorescent lighting used. A control room in which is kept an up-to-the-minute picture of the many thousands of parts which are being produced daily is shown in the accompanying pictures.
Work on the first site began, it is reported, nearly 2,000 years ago, when, from Roman times to the present, generations of quarry workers hewed out the avenues and streets now paved with cement.
Every inch of the quarry roof was tested for strength, and, where fissures indicated weaknesses, columns of brickwork were run up from floor to ceiling. But for the most part, the massive irregular buttresses left by each generation of quarrymen made such precautions unnecessary.
To meet the demands for still greater space, however, another million cubic yards were excavated. Three wide shafts were sunk, down which air is forced by fans. Four others take away the air no longer fit to breathe. To safeguard against bombing, one intake shaft penetrates into the mine in a sweeping curve; the others are vertical, but capped with concrete slabs several feet thick. Walls and roofs were given a coat of yellow paint to prevent fine dust from falling upon and damaging high-precision machinery.
The workers, men and women, enter and leave by means of four elevators and two escalators. A shaft of exceptional size, topped by a powerful hoist, provides a means of lowering the larger machines into the underground factory and of raising out the heavier and bulkier items produced.
Although we in America have not yet had occasion to go underground in building our war industries, nor anticipate in the near future the necessity of planning to do so, it is interesting to see how the British are adapting themselves to subterranean manufacturing conditions. And while here in the United States we do not have chalk mines, we do have some rather extensive caverns, such as the ·Mammoth Cave in Kentucky and the Carlsbad Caverns in New Mexico, which run in some cases for more than a hundred miles deep underground.
This article was originally published in the May, 1942, issue of Aviation magazine, vol 41, no 5, pp 76, 247.
The original article includes 4 photos.
Photos credited to British Combine.