Air loops play a key role in the Environmental Control and Life Support Subsystems (ECLSS) of manned spacecraft.
They constitute the essential interface between the crew and those ECLSS assemblies which are responsible for crew safety, comfort and health.
Further, air is required to cool avionics and other equipment of the vehicle during the relevant operational phases. Thereby, air loops establish the essential interface between the ECLSS and the Thermal Control Subsystem (TCS).
The paper gives a classification of air loops features of laboratory modules and discusses the design implementation aspects of the various conceptual approaches. Features addressed are centralised - decentralised ECLSS, separated - combined air loops, subfloor architecture, cabin loop ventilation and rack cooling.
Particular emphasis is laid on the presently envisaged design solutions of the COLUMBUS programme elements.