The greatly increased performance of both civil and military aircraft since the Second World War has raised problems undreamt of at an earlier period and, from the simple measures originally introduced to improve pilot’s well-being, have sprung the complex installations which are now essential for human survival and comfort and to ensure the proper functioning of vital equipment carried in present day machines.

The term “Environmental Control System” is used for convenience to cover collectively the various cabin and equipment bay, pressure, temperature and humidity control systems that are fitted.