Aerojet Rocketdyne Mars mission architecture

[RealKerbal3x]

So, looks like Aerojet Rocketdyne has put together a proposed Mars crew mission architecture. Not sure if this is an internal leak, but it's an interesting read nonetheless.

The link doesn't work unless you open it in a new tab, and then copy and paste the link again (for some reason). TL;DR in case you can't access it:

• There are two proposals for this architecture, one using nuclear thermal propulsion and the other nuclear electric propulsion. They both involve constructing a transfer vehicle in Earth orbit, though they differ in the number of launches.
• The launch vehicles used are SLS Block II (for crew and high-value cargo, eg NTR engines), New Glenn (for transfer vehicle truss segments) and Starship (for refuelling).
• Initial missions are short-stay (30 days on the surface), eventually evolving to long-stay missions (450 days)
• The overall mission goal is "the eventual human settlement of Mars", with each surface mission contributing to the construction of an outpost.
• The PDF states reusability as an important element of the architecture, though the crew and cargo surface landers are still single-use.
• The first human steps on Mars would take place in 2037 under this plan.

Overall this architecture seems a little short-sighted to me. Starship is used heavily, but only for orbital refuelling - Mars descent and ascent still rely on small expendable vehicles, limiting surface elements like habitats or rovers to 20t. Starship is designed to land 100+t payloads on Mars, and this system assumes that it works as intended, so why not use it for that?

It also assumes that SLS Block II becomes a thing, continues to operate into at least the late 2040s, and is capable of multiple launches per year. I'd bet on a commercial vehicle being available by then. 

Thoughts?

[Beccab]

58 minutes ago, RealKerbal3x said:

Starship is designed to land 100+t payloads on Mars, and this system assumes that it works as intended, so why not use it for that?

Because then you don't need Aerojet Rockedyne

[kerbiloid]

13 hours ago, RealKerbal3x said:

The launch vehicles used are SLS Block II (for crew and high-value cargo, eg NTR engines), New Glenn (for transfer vehicle truss segments) and Starship (for refuelling).

1. They forgot to involve Heavy Angara and Heavy Longmarch.

2. As SLS, SS, and NG are kinds of antimatter for each other, they should annihilate on contact.

3. No problem with NTR as anyway none of the three LV is already flying.

13 hours ago, RealKerbal3x said:

Initial missions are short-stay (30 days on the surface), eventually evolving to long-stay missions (450 days)

The Martian launch window opens once per two years, and the overall flight takes three.

What are they going to achieve in a month what a robot can't, and how many decades are they going to be hanging in orbit for a month-long stone gathering every three years?

Humans are needed only for mining and building. No mining - why need people?

Surface = gravity and rad protection.

13 hours ago, RealKerbal3x said:

The overall mission goal is "the eventual human settlement of Mars", with each surface mission contributing to the construction of an outpost.

Do they already have the best place for a permanent settlement taking several decades for building (if fly once per two years)?

13 hours ago, RealKerbal3x said:

Overall this architecture seems a little short-sighted to me. Starship is used heavily, but only for orbital refuelling - Mars descent and ascent still rely on small expendable vehicles, limiting surface elements like habitats or rovers to 20t. Starship is designed to land 100+t payloads on Mars, and this system assumes that it works as intended, so why not use it for that?

The Starship is a teaspoon where buckets are needed.