NASA Human Landing System

[tater]

16 minutes ago, cubinator said:

That's because they are using batteries that are not optimized for the job on B4. Those avionics will get a lot lighter.

LSS battery requirements would be a function of stay duration, and insolation at the polar landing site. It has the advantage of being tall. The question becomes how many days would they get little/no solar power generation, then comparing that to power use during lunar night. For a lander required to operate for 2 weeks in pitch black, it might require a lot of battery. if it only has to deal with a few days of true night, the requirement could be considerably lower.

[JoeSchmuckatelli]

Plutonium thermoelectric if you are going to be in shadow that long. 

The ship would have to blow up for it to be at all dangerous (well, any more dangerous than just being in space) 

[tater]

5 minutes ago, JoeSchmuckatelli said:

Plutonium thermoelectric if you are going to be in shadow that long. 

The ship would have to blow up for it to be at all dangerous (well, any more dangerous than just being in space) 

RTGs are fine, or part of the payload can be a Kilopower reactor, deploy it nearby, run a cable to LSS for the mission duration, then move the cable away from the launch site before leaving for the next crew to use it (maybe it powers an ISRU experiment when crew is not there).

What is stunning about the few tanker requirements is that LSS could totally happen with minimal refilling ops—to the point that tankers could be used at a time when they have not even sorted out reuse. If a 100t SS can get to LEO with 150t cargo, then a 60t LSS can get to LEO with 190t of residual props. Means that refilling takes only 3 tankers, and it gets filled to 640t props. That gives the 60t LSS (plus an additional 20t cargo) 8196 m/s dv.

 

 

 

[JoeSchmuckatelli]

All this just reminds me how freaking difficult it is to do this stuff.  Then compare the tonnage to Apollo? 

[StrandedonEarth]

 

[RCgothic]

That's what I was worried about. Now up to 9 months delay on a 4 year program because BO is a poor loser.

[mikegarrison]

42 minutes ago, RCgothic said:

That's what I was worried about. Now up to 9 months delay on a 4 year program because BO is a poor loser.

In my experience, when people fight award contract decisions this hard, it often means they genuinely think they were wronged.

That doesn't necessarily mean they actually were wronged, but if they think they were, don't they have the right to argue it? Mostly teams go into these things thinking they genuinely have the best solution, and often they are shocked when they don't win. That's my experience.

Edited August 19, 2021 by mikegarrison

[mikegarrison]

Let me give a concrete example: the USAF tanker replacement saga.

So, context -- the US has a fleet of KC-135 (based on 707) and KC-10 (based on DC-10) tankers. The KC-135s were getting very old and the USAF wanted to replace them. They worked a deal with Boeing to replace them with 767-based tankers on a lease-back basis that was alleged to be a huge giveaway to Boeing. It turned out that the USAF officer who negotiated the deal basically got kickbacks from Boeing, and people went to prison. Bad conduct by Boeing and the USAF.

So that deal crumbled, and they ended up with a competition. Airbus submitted the A330 and Boeing submitted the 767. Now the A330 is a bigger and more expensive airplane than the 767. The USAF chose the A330, and Boeing filed a protest. The basis of the protest was pretty much that the contract team awarded the A330 a lot of bonus points for being bigger and having more capability, but ignored that the 767 met the actual mission requirements and also ignored some problems caused by the A330 being bigger. The GAO ruled that yes, the contract award had been flawed. Boeing also argued that if they knew the USAF was going to reward people for submitting airplanes that were bigger than they had asked for, they would have submitted the 777.

So a new contract was offered, this time with a more detailed way of assessing the value of exceeding the minimum sizing requirements. IIRC, Boeing submitted both the 767 and the 777. Airbus submitted the A330 again. This time the 767 won. Airbus filed a protest. This time the protest failed.

Now the 767 tanker program has had a lot of teething issues and is behind schedule by quite a bit, but who knows if the same thing would have happened for the A330 or not?

Anyway, as far as I can tell everybody involved thought they were the people in the right.

Edited August 20, 2021 by mikegarrison

[tater]

Blue Origin didn't even submit the actual lander for the whole program, just the minimum lander for Artemis I in 2024 (which is not happening, anyway).

The actual lander was supposed to be "sustainable" and have a crew of 4. Literally nothing about the lander they submitted would be the same for a lander with 2X the crew except maybe components like engines, RCS, etc.

New Ascent Stage for 4, so a substantial mass bump. Also needs to be reusable/refillable (and they'd still be chucking the descent stage every flight).

New Descent Stage. Needs to be able to land the more massive AS, so much larger.

New Tug, since the above stack needs pushing from Gateway. Maybe that can also get refilling.

So way more expensive for 2 crew, and then presumably way, way more expensive for 4. Also, how do they get a larger on to cislunar? The 3 parts can barely go on existing commercial vehicles. Anything larger? Not even NG can do it. Starship as the launch vehicle? SLS? I'd say FH, but fairing diameter might be a problem.

 

Edited August 20, 2021 by tater

[cubinator]

3 hours ago, RCgothic said:

That's what I was worried about. Now up to 9 months delay on a 4 year program because BO is a poor loser.

Luckily the SpaceX program seems to be able to progress on its own. 

[Terwin]

10 minutes ago, cubinator said:

Luckily the SpaceX program seems to be able to progress on its own. 

This may even be a boon for SpaceX, as now the dead-lines are pushed-back by 9 months, giving them more lee-way for unexpected delays.  As payments are based on performance, and not schedules,  only payments for mile-posts passed during the actual review would be delayed.

So, as long as SpaceX still has the contract in the end, they may well end up better off than if there was no challenge. 

[tater]

Starship continues, and the long-pole aspects are not Lunar Starship, but just maing SS work in the first place.

[JoeSchmuckatelli]

11 hours ago, tater said:

Starship continues, and the long-pole aspects are not Lunar Starship, but just maing SS work in the first place.

That's kind of the key, here, isn't it. 

SX showcased an independent effort to develop their own ship - and looks to be moving forward in a way that demonstrates likely success.  If they're able to make SS/SH work to do their own (SX) thing... repurposing a single SS (or specifically building a SS to meet contractual requirements) is easy (relatively).  Like saying 'a station wagon is great - but I want easier access to the cargo area' and you end up with...

The El Camino

 

Edited August 20, 2021 by JoeSchmuckatelli

[tater]

 

Sad, since XEUS is actually pretty awesome.

[SpaceFace545]

On 8/20/2021 at 12:13 AM, tater said:

Starship continues, and the long-pole aspects are not Lunar Starship, but just maing SS work in the first place.

I think that's a good thing, I'm no fan of starship but it's gonna let them focus on their main goals and aspirations instead of focusing on an okay lander

[tater]

ULA is Boeing and LockMart as we all know.

ULA could have submitted designs they have literally in their back pocket—the whole XEUS concept started maybe before 2014? ULA went from the original Centaur based concept with Masten doing the landing engines to one based on ACES.

XEUS is everything Dynetics entry sort of looked like, except ULA and Masten can do math, and they already know it closes.

[derega16]

1 hour ago, tater said:

ULA is Boeing and LockMart as we all know.

ULA could have submitted designs they have literally in their back pocket—the whole XEUS concept started maybe before 2014? ULA went from the original Centaur based concept with Masten doing the landing engines to one based on ACES.

XEUS is everything Dynetics entry sort of looked like, except ULA and Masten can do math, and they already know it closes.

Maybe because XEUS required the D word to work?

[mikegarrison]

[magnemoe]

23 minutes ago, mikegarrison said:

Now the idea of switching from main engines to landing engines is a lot like moonship plan and landing sideways make cargo unloading easy. 
An popular KSP idea I realized. 
However the frame is looks very heavy even if its carbon fiber and an lack of fuel tanks. 

[tater]

 

[kerbiloid]

3 hours ago, magnemoe said:

However the frame is looks very heavy even if its carbon fiber and an lack of fuel tanks. 

It's hollow inside as any bar in aviation. Pipes, not logs.

[magnemoe]

7 hours ago, kerbiloid said:

It's hollow inside as any bar in aviation. Pipes, not logs.

That is given, however then using pipes as structure you don't want the pipes to have to large diameter it make them heavier or to thin walled. 
Diameter depend on material, diameter is much larger for carbon fiber than steel. This is very visible on bicycle frames who is an excellent example as both materials are common.

Yes, I know this is an model who has to work with the model constrains  

Edited August 22, 2021 by magnemoe

[Beccab]

14 hours ago, tater said:

XEUS is everything Dynetics entry sort of looked like, except ULA and Masten can do math, and they already know it closes.

But it would be a lunar lander that is actually a modified upper stage, can you imagine the absurdity of such a thing? I already hear the screams

[kerbiloid]

1 hour ago, magnemoe said:

Yes, I know this is an model who has to work with the model constrains

I guess they just had taken a crane jib and attached a lizard-like ogive cabin, lizaed-like legs, and lizard-like nozzles.

***

The Wise Ancients knew how to can into Moon base.
http://www.astronautix.com/l/lunarbases.html

[magnemoe]

37 minutes ago, Beccab said:

But it would be a lunar lander that is actually a modified upper stage, can you imagine the absurdity of such a thing? I already hear the screams

LOL, yes but design looks good.

http://www.developspace.info/plan/images/xeus.jpg

http://www.developspace.info/plan/xeus.html

An realistic version of the above belly lander. It should be pretty capable of moon SSTO missions even if most has an detachable return module, yes this require refueling in moon orbit. 
Munlander kind of brute forcing it. Yes it would be very nice for building bases on the moon but a bit oversize for small science missions.