Someone in comments mentioned an interesting idea for the 2-man architecture I’ve been discussing, and I wanted to see if I could solicit some further commentary.
Basically, the current iteration of the 2-man architecture I’ve been looking into has an up to 8400lb manned capsule, a 1600lb “light lander cabin”, a 2400lb drymass lander, and somewhere between 8000 and 9000lb of lander propellants (I don’t have my own spreadsheet up at the second). Someone suggested using a Soyuz capsule with the thicker reentry shield tested out during the Zond program for lunar returns. Apparently the reentry capsule part of the Soyuz is somewhere in the ~6500lb range fully loaded. But ~2000lb of that is supposedly listed as cargo (if Mark Wade has his numbers right), and about 560lb of that is astronauts, which probably shouldn’t be double counted.
Unfortunately, the Soyuz spacecraft is actually a three-piece design. There’s a propulsion/power module on the back, the capsule in the middle, and an “orbital module” on the front. The fully loaded Soyuz with all the goodies is about 15klb, which is too much. If you could drop the propulsion/power module, and not bring a bunch of cargo, you’d could probably fit the orbital module and the reentry capsule with a heavier Zond-style shield into the mass budget for the mission. And it’s a 3 person design instead of two-person one.
You might be able to get away without the propulsion module on the back. When the Soyuz is launched into orbit, it’ll be on top of the lander, which can provide RCS functionality and probably will have some onboard solar panels. When left in orbit, it’ll be attached to the Centaur with a lunar mission kit, which will also have solar power, and be able to provide some RCS functions. Maybe. Would something like this work? I’m not sure if you could add enough solar power capacity to the Centaur within the mass budget of the “lunar mission kit” to provide all the power the centaur needs. It might work, but I don’t know enough about the Soyuz personally.
If this does work, there are a couple of benefits:
- If you can use a stock Soyuz orbital module and reentry capsule (with a Zond shield), you could potentially eliminate one of the most expensive pieces of hardware in the project.
- The architecture becomes a 3-man architecture, since the Soyuz is designed for 14 days of occupation.
- It might just be possible to size things such that the lander itself could take all three down to the surface, which would make it more capable than Apollo, but far more affordable.
There are also some drawbacks:
- NASA would never do a return to the moon using Russian hardware for such a visible part of the architecture. And if you’re doing it commercially, there are probably better ways (which I’ll go into in another post) of doing things.
- A stock Soyuz vehicle even if the power and RCS issues could be taken care of is going to be very cramped for that long of a trip.
But once again, as I said, I’m kind of out of my league on Soyuz design stuff. Does anyone here have better information on whether this is feasible or not? If it is, it makes some things with this architecture a lot easier. Paging David Anderman?
Latest posts by Jonathan Goff (see all)
- Unorthodox Reusable Lunar Landers Concepts - June 12, 2021
- Goff Family 2021 Summer Sabbatical Part 1: Utah Trip - June 1, 2021
- Transitions and Summer Sabbatical - May 31, 2021