9) The Stratosphere Chamber

          THE STRATOSPHERE CHAMBER

 From a page in the booklet "Test or be damned". 

 Published by Vickers-Armstrongs (Aircraft) Ltd. C 1962

The high-altitude test chamber was designed by our Aeronautical  Research and Development Department to enable tests to be carried out

under conditions of extreme cold and altitude. The required temperature, humidity  and pressure can be maintained almost indefinitely and varied at    will  to produce snow storms, icing and other meteorological phenomena likely to be encountered.

All this can be superimposed on the actual pressure differentials  which the fuselage of the aircraft will undergo on a typical commercial flight. Thus a very close approximation to the severest flight conditions can be repeatedly imposed on the aeroplane under the  eyes of our test engineers. Similar tests can be carried out on  components and equipment.

The chamber consists of an insulated welded steel cylinder 50 feet  long and 25 feet in diameter. The chamber is “fed” by vacuum pumps,  and has refrigeration and humidity control equipment. The pressure  range is from sea level to 80,000 feet and temperature range from -65°C. to at least + 55°C. Initial rates of Climb vary from 1,500 feet  per minute with the chamber air at + 55°C. to 1,000 feet per minute at  60°C.

This unique facility, the largest of its kind in the world, has been used in several fields besides aviation. On January 25th, 1955, two  trawlers, the Lorella of 558 tons and Roderigo of 810 tons, were lost with all hands, north of Iceland. Tests carried out on a l/12th scale  l7ft. long model, of the trawler Kingston Garnet, showed that under  Arctic conditions ice formed on the rigging to such an extent that the weight caused the trawler to capsize.