Multi-role capsules: fulfilling their potential

No national space programme has undertaken either the acquisition or operation of more than one crew transportation system at one time, therefore such a development should maximise the mission roles it can undertake. It is shown only capsules can fulfil all the roles required for complete and sustained in-orbit operations. However safety considerations show that when combined with an expendable launch system safety concerns limit the extent that a capsule can be used to deliver crews to orbit. It follows that a capsule should be designed to maximise its multi-role capability with an emphasis on roles other than crew delivery, which should be later undertaken by reusable systems. It is shown that with technology advances since the 1960s, capsules can be made with considerably greater potential as multi-role systems. This is illustrated with a feasibility design of a capsule of around 10 tonne fuelled weight and capable of carrying four people on a very wide range of missions. The conclusion reached is that a multi-purpose capsule can be a very high value investment, providing an effective way of doing many missions in both expendable and reusable launch system environments. However to get this potential the capsule has to be carefully specified, and employ the best of systems thinking in its implementation.