Scaling down spaceship for early launches | Spacecraft Engineering Workgroup | Forum

I have been thinking more about the order in which the various aspects of the CLLARE project will progress.

Obviously the very first thing we will need to get working is the Selene 1 rocket.

Once this works it seems sensible to begin work on the space capsule since we could then do manned suborbital flights (unmanned test flights with dummy capsules first, of course).

It occurred to me that the capsule for these flights could be significantly scaled down from the "real deal".  Obviously it should be structurally identical, since we will want to make sure we have our designs right in that respect.  But many subsystems could be safely scaled down or even eliminated.

For instance, the early Mercury flights were often well under half an hour in duration.  I suspect that on that timescale, there is simply no need for CO2 scrubbing or humidity control, whereas those will be vital on the actual mission.  We will need communication gear on these early flights but it will not need to be powerful enough to work over lunar distances.  We will need navigation solutions, but accuracy will not be paramount and GPS will work for a considerable portion of the trip.

In other words, aside from the structure of the capsule itself, just about everything else could function in a reduced capacity.  This would make those early flights cheaper and easier (since it would keep down capsule mass).

However, we will need to consciously prepare for making this approach possible.  The decisions about whereabouts various systems are placed in the capsule (inside or outside of the internal pressure vessel, if we do go with that approach) and how they are connected together will have to be made such that we can effectively "chop and change" items about with as few consequences as possible.  I don't know to what extent this approach will be possible, but we should probably strive for it wherever we can.