Author Topic: SLS Lander?  (Read 21762 times)

Offline Caleb Cattuzzo

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SLS Lander?
« on: 02/16/2018 05:46 pm »
I was wondering if NASA has said anything about a lunar lander for any EM missions?I know the SLS can carry cargo and the orion for the DSG station but i was wondering if they were going to put a lander in the SLS for a mission or missions?Plus after the presidents recent speech wanting america to return to the moon will NASA start one if they haven't yet?
« Last Edit: 02/16/2018 05:48 pm by Caleb Cattuzzo »
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Offline whitelancer64

Re: SLS Lander?
« Reply #1 on: 02/16/2018 05:59 pm »
A lunar lander is not in any NASA plans or proposals, nor is there any budget for one.
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Offline Caleb Cattuzzo

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Re: SLS Lander?
« Reply #2 on: 02/16/2018 06:09 pm »
A lunar lander is not in any NASA plans or proposals, nor is there any budget for one.

Is it possible with SLS though?
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Offline whitelancer64

Re: SLS Lander?
« Reply #3 on: 02/16/2018 06:55 pm »
A lunar lander is not in any NASA plans or proposals, nor is there any budget for one.

Is it possible with SLS though?

Not without funding.
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Offline RonM

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Re: SLS Lander?
« Reply #4 on: 02/16/2018 07:16 pm »
Of course it's possible, just like the Altair concept for Ares V, but there are no plans and no funding for a lunar lander.

https://en.wikipedia.org/wiki/Altair_(spacecraft)

Offline Rocket Science

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Re: SLS Lander?
« Reply #5 on: 02/16/2018 07:24 pm »
No, it's still a rocket to nowhere...
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Offline Hog

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Re: SLS Lander?
« Reply #6 on: 02/16/2018 08:43 pm »
"Build it, they will come."

I wish the focus wasn't being directed back to Luna, but if we're to plant flags and footprints on the Moon again, so be it.

Orion with some landing legs and an OMS engine should work.

NASA just released an RFI for a Shuttle'like OMS engine
Article by Chris Gebhardt
https://www.nasaspaceflight.com/2018/02/nasa-releases-rfi-new-orion-service-module-engine/


Here's Endeavours edit:LEFT side OMS pod.  .
« Last Edit: 02/16/2018 08:46 pm by Hog »
Paul

Offline Toast

Re: SLS Lander?
« Reply #7 on: 02/16/2018 09:24 pm »
Blue Origin (among others) has a proposal for a lander capable of flying on SLS, but it wouldn't carry crew. But like everybody else has been saying, it won't happen without funding. And Congress likes to talk about going back to the moon (and about going to Mars) but doesn't like ponying up the money to actually do so.

Offline whitelancer64

Re: SLS Lander?
« Reply #8 on: 02/16/2018 09:32 pm »
"Build it, they will come."

I wish the focus wasn't being directed back to Luna, but if we're to plant flags and footprints on the Moon again, so be it.

Orion with some landing legs and an OMS engine should work.

NASA just released an RFI for a Shuttle'like OMS engine
Article by Chris Gebhardt
https://www.nasaspaceflight.com/2018/02/nasa-releases-rfi-new-orion-service-module-engine/


Here's Endeavours edit:LEFT side OMS pod.  .

Orion's already using an OMS for its service module. It would need about 20X more fuel to land on the Moon, though, and more to lift off again and break lunar orbit.

A dedicated lander is a much more efficient option.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
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Offline ncb1397

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Re: SLS Lander?
« Reply #9 on: 02/16/2018 11:55 pm »
"Build it, they will come."

I wish the focus wasn't being directed back to Luna, but if we're to plant flags and footprints on the Moon again, so be it.

Orion with some landing legs and an OMS engine should work.

NASA just released an RFI for a Shuttle'like OMS engine
Article by Chris Gebhardt
https://www.nasaspaceflight.com/2018/02/nasa-releases-rfi-new-orion-service-module-engine/


Here's Endeavours edit:LEFT side OMS pod.  .

Orion's already using an OMS for its service module. It would need about 20X more fuel to land on the Moon, though, and more to lift off again and break lunar orbit.

Actually, if you take the 4700 kg LEM ascent module and plop it on the ESM, it would have ~1800 m/s. Pretty much exactly what you would need to land on the moon with no margin from LLO. Main problem is main propulsion thrust. ESM has about 30 kN, while LEM had ~50% more than that I believe while the whole stack would be heavier because of the heavier ESM. IMO the Orion program just needs to build an american propulsion/power service module that just happens to do double duty as a descent module.

A lunar lander is not in any NASA plans or proposals, nor is there any budget for one.

Well, the new budget request has $100 million+ for lunar landing tech(starting with <200 kg landers, expanding to 5000-6000 kg eventually) and $200 million+ for lunar surface missions under the science division.
« Last Edit: 02/17/2018 12:09 am by ncb1397 »

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #10 on: 02/17/2018 03:16 am »
{snip}
A lunar lander is not in any NASA plans or proposals, nor is there any budget for one.

Well, the new budget request has $100 million+ for lunar landing tech(starting with <200 kg landers, expanding to 5000-6000 kg eventually) and $200 million+ for lunar surface missions under the science division.

The landers are being developed under Lunar CATALYST, they will need payloads. Habitats are being ground prototyped under NextSTEP.

The 5000-6000 kg lander is probably the XEUS from ULA and Masten Space Systems. They are milestoned to release information within the next couple of months. It will need a cabin. I predict that people will dismount from that Centaur.

Offline Joseph Peterson

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Re: SLS Lander?
« Reply #11 on: 02/18/2018 12:05 am »
I'm having trouble visualizing a Lunar lander lander that works in conjunction with SLS/Orion/DSG.  From the Lunar orbits and their potential uses topic[1] it appears we need roughly 700 m/s to go from a Lunar/L2 orbit Orion can reach to LLO.  LLO to the surface adds another ~1800 m/s.

Is it better to build a ~5 km/s reusable lander that can go directly to the surface or break the trip into stages?

If staging makes sense does it make more sense to build a DST that can reach all potential LLO staging orbits, an ACES-esque tug, a SEP tug, disposable options, or something I haven't considered?

Is a ~3.6 km/s fully reusable lander preferable to disposable or partially disposable options?

Obviously there needs to be funding to pay for whatever option is chosen.  I'm more interested in the possible hows for now.  As far as I can tell, we just don't know enough about where or how often we might want to land to actually start designs, but doesn't mean we can't speculate, right?

[1] https://forum.nasaspaceflight.com/index.php?topic=41784.0

Offline Steven Pietrobon

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Re: SLS Lander?
« Reply #12 on: 02/18/2018 03:52 am »
Is it better to build a ~5 km/s reusable lander that can go directly to the surface or break the trip into stages?

An expendable system gets you to the Moon faster and with less hardware, since you don't need to build a gateway and the lander can be smaller, since it only needs to do 4 km/s from LLO instead of 5 km/s from NRO. You also don't need to worry about maintaining the lander and transferring propellants and cargo to the lander. The disadvantage is that you  need a new lander for every mission, but if you are only going every six months or so, that might not be so bad.
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Offline Joseph Peterson

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Re: SLS Lander?
« Reply #13 on: 02/18/2018 05:01 am »
Is it better to build a ~5 km/s reusable lander that can go directly to the surface or break the trip into stages?

An expendable system gets you to the Moon faster and with less hardware, since you don't need to build a gateway and the lander can be smaller, since it only needs to do 4 km/s from LLO instead of 5 km/s from NRO. You also don't need to worry about maintaining the lander and transferring propellants and cargo to the lander. The disadvantage is that you  need a new lander for every mission, but if you are only going every six months or so, that might not be so bad.

I am trying to figure out how a Lunar surface exploration program could work with SLS/Orion/DSG.  Obviously not having to design build permanent infrastructure should speed up the process.  That is not the path we are currently on.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #14 on: 02/18/2018 10:21 am »

I am trying to figure out how a Lunar surface exploration program could work with SLS/Orion/DSG.  Obviously not having to design build permanent infrastructure should speed up the process.  That is not the path we are currently on.

The DSG's Power and Propulsion Element (PPE) is a solar powered space tug. A second one can be used to push consumables like food, water and power from LEO to a spacestation orbiting the Moon. Heavy items like habitat building and lunar rovers can also be transferred.

Since payload, propellent and lander can arrive separately heavier items can be landed on the Moon from a spacestation than in a single launch.

The ideal orbit for the DSG during construction of a Moon Base is probably very different from the orbit of the ship yard for the Mars Transfer Vehicle. Fortunately the DSG's orbit can be changed or a second one built.

People could go on direct SLS/Orion flights to the DSG. Most cargo could be launched to LEO on commercial launch vehicles.

Offline Lar

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Re: SLS Lander?
« Reply #15 on: 02/18/2018 12:42 pm »
Good analysis. For extra credit, cost the same set of operations using FH launches and Dragon spacecraft instead. Don't worry, Congress won't, so SLS/Orion is safe, but it's an interesting exercise.
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Offline Joseph Peterson

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Re: SLS Lander?
« Reply #16 on: 02/18/2018 07:17 pm »

The DSG's Power and Propulsion Element (PPE) is a solar powered space tug. A second one can be used to push consumables like food, water and power from LEO to a spacestation orbiting the Moon. Heavy items like habitat building and lunar rovers can also be transferred.

Since payload, propellent and lander can arrive separately heavier items can be landed on the Moon from a spacestation than in a single launch.

The ideal orbit for the DSG during construction of a Moon Base is probably very different from the orbit of the ship yard for the Mars Transfer Vehicle. Fortunately the DSG's orbit can be changed or a second one built.

People could go on direct SLS/Orion flights to the DSG. Most cargo could be launched to LEO on commercial launch vehicles.

So your saying we should operate two stations then?

Here is what I am envisioning for crewed missions with two stations.

- SLS launches Orion to DSG located at a halo orbit around EML1/2.
- Orion arrives at DSG 5(EML1)-8(EML2) days later.  Crew transfers to DSG.
- Crew departs DSG on (DST???) for LLO station 0-7 days later depending on station orbital positions.
- Crew arrives at LLO station 59+ hours later using 680 m/s+ using chemical propulsion.  The + depends on which LLO orbit is used.  Current SEP will increase travel time by an amount I haven't yet learned to calculate.
- Crew departs LLO station for Lunar surface.
- Lunar surface operations are conducted.
- Crew returns using above steps in reverse.

Good analysis. For extra credit, cost the same set of operations using FH launches and Dragon spacecraft instead. Don't worry, Congress won't, so SLS/Orion is safe, but it's an interesting exercise.

Assuming a few minor modifications, a man-rated FH with a disposable center core at $95M launching Dragon II is capable transporting a crew of two to NRHO with Dv to spare.  I would expect a single crew transfer mission would cost on the order of $200M.  To equal SLS/Orion's crew of four we'd be looking at ~$400M.  Replacing SLS/Orion single piece cargo capability would require a another FH launch, meaning FH/Dragon should more than completely replace SLS/Orion's capability for somewhere near $500M.  Since the rest of the architecture is fuzzy I'll stop the comparison with the $1.5-2.5B estimate to launch SLS/Orion.

I don't understand why we would bother with the same set of operations using FH/Dragon.  Instead, I'd replace Dragon's trunk with enough Dv for LLO insertion and the TEI burn.  This allows surface exploration to commence with only one station, no interstation transport required, while allowing for a sub 4 km/s lander.  Then again, my assumption is early Lunar exploration will focus on the poles, tourists will accept 48-72 hour trips to Apollo 11 Lunar park, and other locations are explored using robots with sample returns run through the LLO station.  86° covers all of these options sooner.  Transfer times are 3-5 days to LLO versus the 8-20 via L1/2 halos.

While this is an interesting thought exercise, I don't see how it gets us closer to the specifications a Lunar lander designed to work with SLS/Orion requires.

Offline ncb1397

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Re: SLS Lander?
« Reply #17 on: 02/18/2018 08:01 pm »

While this is an interesting thought exercise, I don't see how it gets us closer to the specifications a Lunar lander designed to work with SLS/Orion requires.

The solution is an upgraded Orion service module made in the United States. Bump the solar power capability to 20 kw from 11 kw to match NeMO, add Next-C or AEPS engines. Acting as a lunar lander, It could self ferry itself ahead of crew to whatever orbit Orion can reach(might even be considered LLO) with the upgraded service module utilizing the extra lift capability of the Block 1B. The descent modules get re-used on the surface for power, consumable storage, fuel storage. Once you get some sort of fuel production going on the surface, you could look at fueling them and sending them back up to orbit. Orion would just use ESMs until this is available, freeing up Europe to focus on other stuff (like a European lunar hab equivalent to their contribution to ISS).

Either that or base the lander at DSG like what seems to be the plan. The difference between 4.5 km/s and 5.5 km/s for a lander isn't exactly a deal breaker.
« Last Edit: 02/18/2018 08:09 pm by ncb1397 »

Offline Joseph Peterson

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Re: SLS Lander?
« Reply #18 on: 02/18/2018 09:14 pm »

While this is an interesting thought exercise, I don't see how it gets us closer to the specifications a Lunar lander designed to work with SLS/Orion requires.

The solution is an upgraded Orion service module made in the United States. Bump the solar power capability to 20 kw from 11 kw to match NeMO, add Next-C or AEPS engines. Acting as a lunar lander, It could self ferry itself ahead of crew to whatever orbit Orion can reach(might even be considered LLO) with the upgraded service module utilizing the extra lift capability of the Block 1B. The descent modules get re-used on the surface for power, consumable storage, fuel storage. Once you get some sort of fuel production going on the surface, you could look at fueling them and sending them back up to orbit. Orion would just use ESMs until this is available, freeing up Europe to focus on other stuff (like a European lunar hab equivalent to their contribution to ISS).

Either that or base the lander at DSG like what seems to be the plan. The difference between 4.5 km/s and 5.5 km/s for a lander isn't exactly a deal breaker.

That isn't the current plan though.  NASA's RFI requested drop-in replacements for Shuttle OMS engines.  I guess the SM tanks could be stretched but that will cut into payload capacity.  How long would it take and how much would it cost before an upgraded Orion would be available?  How many more SLS launches are needed to send cargo?

https://www.nasaspaceflight.com/2018/02/nasa-releases-rfi-new-orion-service-module-engine/

Why are you adding a ~20% margin for LLO to surface and back compared to a minimum margin of ~9% for L2 halo orbits?

LLO to Lunar surface with no plane changes is ~1.87 km/s.  L2 to Lunar surface with no plane changes is ~2.52 km/s.  The NRHO version with the same margins as a 4.5 km/s LLO lander needs ~6 km/s.  Plane changes would be required for robotic sample return or <72 hour crewed access to the entire surface from halo orbits so we only have a partial equivalency.

I should probably make it clear that I am not arguing against the use of L1/2 stations in the future.  Once Lunar sourced propellant is available in sufficient quantity, they make perfect sense.  I'm not trying to plan an inner solar system transportation network using existing Lunar propellant production capacity though.  What I am trying to understand is how DSG actually helps locating, then building, Lunar production capacity.  It would seem to me that it is hard to compete with LLO when SEP can replace ~25% of cargo lander chemical Dv using LLO.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #19 on: 02/18/2018 10:55 pm »

The DSG's Power and Propulsion Element (PPE) is a solar powered space tug. A second one can be used to push consumables like food, water and power from LEO to a spacestation orbiting the Moon. Heavy items like habitat building and lunar rovers can also be transferred.

Since payload, propellent and lander can arrive separately heavier items can be landed on the Moon from a spacestation than in a single launch.

The ideal orbit for the DSG during construction of a Moon Base is probably very different from the orbit of the ship yard for the Mars Transfer Vehicle. Fortunately the DSG's orbit can be changed or a second one built.

People could go on direct SLS/Orion flights to the DSG. Most cargo could be launched to LEO on commercial launch vehicles.

So your saying we should operate two stations then?

{snip}

More like 3 spacestations.
LEO gateway spacestation to load SEP and chemical tugs.
LLO spacestation to garage lunar lander.
EML-1/2 spacestation for loading and repair of Mars transfer vehicles.

I think the manned Mars trip is 20-30 years away.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #20 on: 02/18/2018 11:28 pm »
{snip}
I should probably make it clear that I am not arguing against the use of L1/2 stations in the future.  Once Lunar sourced propellant is available in sufficient quantity, they make perfect sense.  I'm not trying to plan an inner solar system transportation network using existing Lunar propellant production capacity though.  What I am trying to understand is how DSG actually helps locating, then building, Lunar production capacity.  It would seem to me that it is hard to compete with LLO when SEP can replace ~25% of cargo lander chemical Dv using LLO.

I suspect that the DSG, or replacement e.g. Bigelow/ULA depot, will end up in LLO.

For the Moon base a Bigelow B330-MDS module would mass 20-30 tonnes. That is payload to the transportation system since the mass of the lander and propellant are additional to that.
https://en.wikipedia.org/wiki/B330

Offline Joseph Peterson

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Re: SLS Lander?
« Reply #21 on: 02/19/2018 12:30 am »

The DSG's Power and Propulsion Element (PPE) is a solar powered space tug. A second one can be used to push consumables like food, water and power from LEO to a spacestation orbiting the Moon. Heavy items like habitat building and lunar rovers can also be transferred.

Since payload, propellent and lander can arrive separately heavier items can be landed on the Moon from a spacestation than in a single launch.

The ideal orbit for the DSG during construction of a Moon Base is probably very different from the orbit of the ship yard for the Mars Transfer Vehicle. Fortunately the DSG's orbit can be changed or a second one built.

People could go on direct SLS/Orion flights to the DSG. Most cargo could be launched to LEO on commercial launch vehicles.

So your saying we should operate two stations then?

{snip}

More like 3 spacestations.
LEO gateway spacestation to load SEP and chemical tugs.
LLO spacestation to garage lunar lander.
EML-1/2 spacestation for loading and repair of Mars transfer vehicles.

I think the manned Mars trip is 20-30 years away.

I hadn't considered EO stations.  I prefer NASA not own ISS-2.  My opinion on EO stations is the best way to get commercial stations is to design NASA missions that sign long-term leases for research projects based on the stations.  This doesn't really work in conjunction with plans to transfer ISS funding to SLS/Orion/DSG.

In order to avoid failing into a deep depression, I try to avoid thinking about Mars missions that involve SLS.  The last timeline I stumbled across has Martian orbital missions beginning in the early 2040's.  If Congress actually cared about humans on Mars, they'd shovel a couple billion per year in SpaceX's direction and get out of the way.  Even without government funding, I expect SpaceX can still get to Mars far sooner than 2040.  As such, I think it is best to limit landers used in conjunction with SLS to plausible targets like NEOs or, pending what I learn in this conversation, the Lunar surface.

I suspect that the DSG, or replacement e.g. Bigelow/ULA depot, will end up in LLO.

For the Moon base a Bigelow B330-MDS module would mass 20-30 tonnes. That is payload to the transportation system since the mass of the lander and propellant are additional to that.
https://en.wikipedia.org/wiki/B330

If it were up to me I'd spend the $2.3B on the Bigelow/ULA offer, and build the SEP PPE module.  The PPE would be launched with a small multi-port module as close to LLO as a FH can get and let the PPE take care of the rest.  B330-ACES docks with the PPE and we have most of a station core, plus an ACES that can be reused.  Orion still won't be able to return without an upgrade or refueling, but at least we have useful hardware out there.

Offline ncb1397

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Re: SLS Lander?
« Reply #22 on: 02/24/2018 02:45 pm »

While this is an interesting thought exercise, I don't see how it gets us closer to the specifications a Lunar lander designed to work with SLS/Orion requires.

The solution is an upgraded Orion service module made in the United States. Bump the solar power capability to 20 kw from 11 kw to match NeMO, add Next-C or AEPS engines. Acting as a lunar lander, It could self ferry itself ahead of crew to whatever orbit Orion can reach(might even be considered LLO) with the upgraded service module utilizing the extra lift capability of the Block 1B. The descent modules get re-used on the surface for power, consumable storage, fuel storage. Once you get some sort of fuel production going on the surface, you could look at fueling them and sending them back up to orbit. Orion would just use ESMs until this is available, freeing up Europe to focus on other stuff (like a European lunar hab equivalent to their contribution to ISS).

Either that or base the lander at DSG like what seems to be the plan. The difference between 4.5 km/s and 5.5 km/s for a lander isn't exactly a deal breaker.

That isn't the current plan though.  NASA's RFI requested drop-in replacements for Shuttle OMS engines.  I guess the SM tanks could be stretched but that will cut into payload capacity.  How long would it take and how much would it cost before an upgraded Orion would be available?  How many more SLS launches are needed to send cargo?

https://www.nasaspaceflight.com/2018/02/nasa-releases-rfi-new-orion-service-module-engine/

Why are you adding a ~20% margin for LLO to surface and back compared to a minimum margin of ~9% for L2 halo orbits?


Why would a better service module cut into payload capacity? You would likely get more capability from the service module to maneuver co-manifested payloads than you would lose from the EUS. The numbers I give for landers are from the following white paper on page 4(Figure 3):

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150019648.pdf

Their emails are on the paper if you would like to ask them directly.

Offline Jim

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Re: SLS Lander?
« Reply #23 on: 02/26/2018 12:24 pm »
  If Congress actually cared about humans on Mars, they'd shovel a couple billion per year in SpaceX's direction and get out of the way.

That is not how it works.  the congress never directly funds a company.

Offline Welsh Dragon

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Re: SLS Lander?
« Reply #24 on: 02/26/2018 02:05 pm »
  If Congress actually cared about humans on Mars, they'd shovel a couple billion per year in SpaceX's direction and get out of the way.

That is not how it works.  the congress never directly funds a company.
Except of course that it (bizarrely to a European) mandates specific rockets for specific missions, thereby ensuring the manufacturers of those rockets get funded.

Offline IRobot

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Re: SLS Lander?
« Reply #25 on: 02/26/2018 02:26 pm »
More like 3 spacestations.
LEO gateway spacestation to load SEP and chemical tugs.
LLO spacestation to garage lunar lander.
EML-1/2 spacestation for loading and repair of Mars transfer vehicles.

I think the manned Mars trip is 20-30 years away.
LLO does not seem necessary nor offer any significant advantage.

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Re: SLS Lander?
« Reply #26 on: 02/26/2018 05:26 pm »
LLO does not seem necessary nor offer any significant advantage.

It can, if you use it to avoid having to take your TEI fuel (and possibly rocket engine) down to the moon and back.

Offline Lar

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Re: SLS Lander?
« Reply #27 on: 02/26/2018 05:39 pm »
  If Congress actually cared about humans on Mars, they'd shovel a couple billion per year in SpaceX's direction and get out of the way.

That is not how it works.  the congress never directly funds a company.
Except of course that it (bizarrely to a European) mandates specific rockets for specific missions, thereby ensuring the manufacturers of those rockets get funded.
I think they mandate things that only a particular rocket (or company) has. This is pretty common in government generally here these days.
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Offline spacenut

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Re: SLS Lander?
« Reply #28 on: 02/26/2018 06:09 pm »
Wouldn't ELM-1 or 2 be a better location for a station and design a lander to be refueled there?  Most companies and countries can reach these locations with existing rockets.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #29 on: 02/26/2018 07:46 pm »
LLO does not seem necessary nor offer any significant advantage.

It can, if you use it to avoid having to take your TEI fuel (and possibly rocket engine) down to the moon and back.

Space activities will always be mass limited. Colonisation will also be very money limited. Astrobotic Technology are currently charging $1,200,000 per kilogram to land a payload on the Moon. Even if larger landers get the price down to $100,000/kg transporting ten tonnes of fuel would cost

10,000 * $100,000 = $1,000,000,000

Bigelow claims it will sell you a spacestation for that billion dollars (placement extra).

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #30 on: 02/26/2018 08:16 pm »
Wouldn't ELM-1 or 2 be a better location for a station and design a lander to be refueled there?  Most companies and countries can reach these locations with existing rockets.

Spacestation at EML-2 Vs. LLO Vs. both is definitely a trade off.

Lunar surface to Low Lunar Orbit (LLO) and back has a delta-v of 2 * 1.87 = 3.74 km/s
Lunar surface to Lagrangian point 2 (EML-2) and back has a delta-v of 2 * 2.52 = 5.04 km/s

A larger delta-v means the landers need much larger fuel tanks and possibly more engines for the same payload.

Various launch vehicles have different prices and deliver significantly different amounts of payload to LLO and EML-2.

Money, mass of payload to lunar surface and location of spacestation can be traded. Unlike Apollo this is a continuing operation so the trade can be over say 10 landings using the same spacestation.

Offline Coastal Ron

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Re: SLS Lander?
« Reply #31 on: 02/26/2018 08:35 pm »
  If Congress actually cared about humans on Mars, they'd shovel a couple billion per year in SpaceX's direction and get out of the way.

That is not how it works.  the congress never directly funds a company.

With earmarks they did (and those might be coming back), and the NASA Authorization Act of 2010 was specific enough in it's requirements that both Boeing and Lockheed Martin did not have to bid to "win" the new work - NASA used novation to swap out the Constellation contracts for the SLS and Orion MPCV contracts.

But to your point, when things are done correctly, Congress is not involved in the contract awards process.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline mike robel

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Re: SLS Lander?
« Reply #32 on: 02/26/2018 09:02 pm »
Even so, earmarks had to flow through a contract; I don't believe they ever when directly form Congress to a vendor...unless of course, they did.

Offline speedevil

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Re: SLS Lander?
« Reply #33 on: 02/26/2018 10:21 pm »
Space activities will always be mass limited. Colonisation will also be very money limited. Astrobotic Technology are currently charging $1,200,000 per kilogram to land a payload on the Moon. Even if larger landers get the price down to $100,000/kg transporting ten tonnes of fuel would cost

10,000 * $100,000 = $1,000,000,000

Bigelow claims it will sell you a spacestation for that billion dollars (placement extra).

Err...
If we're dragging other providers claims into it, SpaceX claims to be able to do it (eventually) for around $50/kg, not $100000/kg.
https://forum.nasaspaceflight.com/index.php?topic=41682.msg1731818#msg1731818
(Assuming numbers applicable to making passenger transport plausible, and detanking and retanking in LEO and LLO with another vehicle. )

Even more near-term launchers (including SLS) can probably comfortably beat $100000/kg.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #34 on: 02/26/2018 11:05 pm »

Err...
If we're dragging other providers claims into it, SpaceX claims to be able to do it (eventually) for around $50/kg, not $100000/kg.
https://forum.nasaspaceflight.com/index.php?topic=41682.msg1731818#msg1731818
(Assuming numbers applicable to making passenger transport plausible, and detanking and retanking in LEO and LLO with another vehicle. )

Even more near-term launchers (including SLS) can probably comfortably beat $100000/kg.

These figures are to the Moon's surface not to LEO.

" around $50/kg"
Which decade?

Offline speedevil

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Re: SLS Lander?
« Reply #35 on: 02/26/2018 11:19 pm »

Err...
If we're dragging other providers claims into it, SpaceX claims to be able to do it (eventually) for around $50/kg, not $100000/kg.
https://forum.nasaspaceflight.com/index.php?topic=41682.msg1731818#msg1731818
(Assuming numbers applicable to making passenger transport plausible, and detanking and retanking in LEO and LLO with another vehicle. )

Even more near-term launchers (including SLS) can probably comfortably beat $100000/kg.

These figures are to the Moon's surface not to LEO.

" around $50/kg"
Which decade?

Whenever you believe P2P level service is plausible.
Note that the BFS, refuelled in LEO can do 20 tons to the lunar surface and back, every three weeks, if it can do Mars at all.

SLS - well - something would need to be rescheduled to get something on the lunar surface before 2030.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #36 on: 02/27/2018 10:09 am »
Currently Falcon Heavy is $90M for 63,800 kg to LEO. That is $1,420/kg
Block 1B SLS is ~$1B for 105,000 kg to LEO. That is $9,524/kg

The LEO to lunar surface round trip is 2 * 5.93 = 11.86 km/s

According to its Wikipedia article the BFR propellant mass is 240,000 kg (530,000 lb) CH4 and 860,000 kg (1,900,000 lb) LOX.

So the fuel for the round trip using Falcons and upper stage BFR refuelled in space would cost at least
(240,000kg + 860,000kg) * $1420/kg = $1,562,000,000

For a 20 tonne payload that is $1,562,000,000 / 20,000kg = $78,100/kg

Offline speedevil

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Re: SLS Lander?
« Reply #37 on: 02/27/2018 11:42 am »
For a 20 tonne payload that is $1,562,000,000 / 20,000kg = $78,100/kg
No, it is not.
See this thread.
In short, 100% reusability slashes costs a lot. If it works, which is a more appropriate topic in other threads.

Re: SLS Lander?
« Reply #38 on: 02/27/2018 11:52 am »
For a 20 tonne payload that is $1,562,000,000 / 20,000kg = $78,100/kg
No, it is not.
See this thread.
In short, 100% reusability slashes costs a lot. If it works, which is a more appropriate topic in other threads.
Assuming it 100% doesn't work is factually wrong, as demonstrated by F9's refurbishment costs of less than half a new core since the 1st ever refurbishment. And that's discounting even a slow, pessimistic improvement in ref. costs overtime.

I understand that A_M_Swallow' post implies using FH to refuel the BFS (with a wrong price/kg quoted).
SpaceX plans to use the BFR for distributed lift, to leverage the economy afforded by fully reusable vehicles.

For his math to make sense, a single (fully reusable) launch of BFS tanker + BFR booster should cost 213 million $ for 150 tons of propellant to LEO. That's probably close to the fully expendable price (consider that SX currently charges 150M$ for a fully expendable FH, with 28 engines and 3 cores)
« Last Edit: 02/27/2018 11:56 am by AbuSimbel »
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Offline A_M_Swallow

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Re: SLS Lander?
« Reply #39 on: 02/27/2018 01:27 pm »
For a 20 tonne payload that is $1,562,000,000 / 20,000kg = $78,100/kg
No, it is not.
See this thread.
In short, 100% reusability slashes costs a lot. If it works, which is a more appropriate topic in other threads.

There are no prices on that thread so it does not support your case.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #40 on: 02/27/2018 01:31 pm »
Currently Falcon Heavy is $90M for 63,800 kg to LEO. That is $1,420/kg
Block 1B SLS is ~$1B for 105,000 kg to LEO. That is $9,524/kg

The LEO to lunar surface round trip is 2 * 5.93 = 11.86 km/s

According to its Wikipedia article the BFR propellant mass is 240,000 kg (530,000 lb) CH4 and 860,000 kg (1,900,000 lb) LOX.

So the fuel for the round trip using Falcons and upper stage BFR refuelled in space would cost at least
(240,000kg + 860,000kg) * $1420/kg = $1,562,000,000

For a 20 tonne payload that is $1,562,000,000 / 20,000kg = $78,100/kg

I calculated the price per kg from the figures on SpaceX's webpage. See
http://www.spacex.com/about/capabilities

If you want to use any other figures you will have to provide believable sources. What a company hopes to happen in 50 years time is not a valid planning figure for the next 10 years.

Re: SLS Lander?
« Reply #41 on: 02/27/2018 01:41 pm »
Again, the price you quote is not right: 90M$ is for the reusable FH, the price for a fully expendable, 63 tons to LEO flight is 150M$.

For distributed lift, SpaceX will use BFR launches, not FH. 7 BFR launches should be enough to fully refuel a BFS in LEO.

If you really care to be objective, I don't think it's reasonable to expect a fully reusable BFR tanker launch in the 2020s to cost 220 million $, or 70 million $ more than a fully expendable FH launch today.
« Last Edit: 02/27/2018 01:46 pm by AbuSimbel »
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Offline Lar

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Re: SLS Lander?
« Reply #42 on: 02/27/2018 04:00 pm »
Agreed. A reusable launch that costs more than the end state construction costs of the vehicles even though you get them back? Very dubious.
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Offline A_M_Swallow

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Re: SLS Lander?
« Reply #43 on: 02/27/2018 04:39 pm »
I did not give a price for the BFR. Just propellant on the Falcon Heavy.

Offline Patchouli

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Re: SLS Lander?
« Reply #44 on: 02/27/2018 07:34 pm »
Related to another SLS Orion thread this could be a good argument for bring into production a regen variant of the LMDE.
That way a common engine can be used on both the Orion SM and a lander.
Hypergolic is the easiest fuel for a lander but it is bad for ISRU so I would consider it not a long term solution.
Plus a Centaur or DCSS derived lander would have a better mass fraction.

Offline brainbit

Re: SLS Lander?
« Reply #45 on: 02/28/2018 10:27 am »
I believe that the DSG is the right project for SLS as it can do this as designed. I also believe the SLS could launch a moon lander to the DSG and this lander could be a mostly USA commercial project, or some other national space agency like ESA's project. I do not think NASA needs to develop a moon lander or moon village. It should be concentrating on what it can do with its budget and political constraints. I do believe commercial flights to the DSG will carry the fuel necessary for the moon lander. It is unfortunate that the politics of the SLS appears to inhibit the development of USA commercial human space flight. It is also unfortunate that these politics will play towards the time line of SLS and that the projected time line of SLS is flawed. It is flawed because of bad decisions made at the start of the SLS. One obvious one is the leaning ML(Mobile Launcher) which they only want to use once. It should not be used at all, and I am glad for our astronauts the leaning ML wont be used for human flight. A question I have is how many other bad design choices have been made and are being hidden with fingers crossed, or until they must be fixed for safety? Unfortunately it is human nature in these over politicized projects for some in authority to hid there mistakes for fear of losing there jobs. Another question I have is why we cannot do science without politics? I will keep my fingers crossed for now.     

Offline yg1968

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Re: SLS Lander?
« Reply #46 on: 03/14/2018 10:29 pm »
This chart shows a lander:

Quote from: Marcia Smith
If you haven't seen it, this is the chart NASA now is using to describe the new exploration plan. #Goddard18

https://twitter.com/SpcPlcyOnline/status/973933081819217920

« Last Edit: 03/14/2018 10:33 pm by yg1968 »

Offline yg1968

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Re: SLS Lander?
« Reply #47 on: 03/14/2018 10:49 pm »
It originally comes from the FY2019 budget slides (slide 11):
https://www.nasa.gov/sites/default/files/atoms/files/nasa_fy_2019_budget_overview.pdf
« Last Edit: 03/14/2018 10:51 pm by yg1968 »


Offline yg1968

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Re: SLS Lander?
« Reply #49 on: 03/14/2018 11:12 pm »
Quote from: Marcia Smith
Gerst - Zurbuchen will partner with companies for small lunar landers.  NASA will do human lunar  landers, but if it turns out industry is more mature and can move faster than us, will reconsider. #Goddard18

https://twitter.com/SpcPlcyOnline/status/973939979272548352
« Last Edit: 03/14/2018 11:12 pm by yg1968 »

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #50 on: 03/15/2018 01:34 am »
This chart shows a lander:

Quote from: Marcia Smith
If you haven't seen it, this is the chart NASA now is using to describe the new exploration plan. #Goddard18

https://twitter.com/SpcPlcyOnline/status/973933081819217920



The chart shows small, medium and large landers. The small landers are Lunar CATALYST so Astrobotic Technology and Moon Express. The Masten Space lander will come along later.

Tipping Point appears to be several projects which are nearly completed.
http://www.spaceref.com/news/viewpr.html?pid=47373

Development of a medium sized lander (500kg-1000kg payload) is due to start later this year.

Development of the Human Lander (5000-6000kg) is show as starting in 2024.

Offline yg1968

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Re: SLS Lander?
« Reply #51 on: 03/15/2018 03:15 am »
The recently released 2018 Global Exploration Roadmap also discusses landers on slide 17:
https://www.globalspaceexploration.org/wordpress/wp-content/isecg/GER_2018_small_mobile.pdf

See this thread for more on this topic:
https://forum.nasaspaceflight.com/index.php?topic=45229.0
« Last Edit: 03/15/2018 03:16 am by yg1968 »

Offline sevenperforce

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Re: SLS Lander?
« Reply #52 on: 03/15/2018 05:55 pm »
I presume that graphic is talking about Blue Moon and similar initiatives, not a man-rated lander.

Offline speedevil

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Re: SLS Lander?
« Reply #53 on: 03/15/2018 06:05 pm »
I presume that graphic is talking about Blue Moon and similar initiatives, not a man-rated lander.
Nope.



Someone dusted off the LM truck plans.

Offline Caleb Cattuzzo

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Re: SLS Lander?
« Reply #54 on: 03/15/2018 07:55 pm »
I presume that graphic is talking about Blue Moon and similar initiatives, not a man-rated lander.
Nope.



Someone dusted off the LM truck plans.

Why build and transport a pressurized rover?I know it extends the eva range extremely but I feel like unless you have a lunar base or your going to reuse it on a different mission then it feels like a waste of payload compared to a light unpressurized rover.This is my opinion though   
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Offline Caleb Cattuzzo

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Re: SLS Lander?
« Reply #55 on: 03/15/2018 07:59 pm »
This chart shows a lander:

Quote from: Marcia Smith
If you haven't seen it, this is the chart NASA now is using to describe the new exploration plan. #Goddard18

https://twitter.com/SpcPlcyOnline/status/973933081819217920

That manned lunar landing date is a little optimistic don't you think?I mean NASA and Roscosmos will have there hands full with DSG and ISS at that time otherwise most of it seems pretty possible to me.
There is no strife,no prejudice,no national conflict in space as yet.Its hazards are hostile to us all.

Offline TrevorMonty

Re: SLS Lander?
« Reply #56 on: 03/15/2018 11:41 pm »
I presume that graphic is talking about Blue Moon and similar initiatives, not a man-rated lander.
Nope.



Someone dusted off the LM truck plans.

Why build and transport a pressurized rover?I know it extends the eva range extremely but I feel like unless you have a lunar base or your going to reuse it on a different mission then it feels like a waste of payload compared to a light unpressurized rover.This is my opinion though   
ESA had FISO presentation few months back where plan was to have two RTG+Solar powered 2man rovers. These could support crew for up to 6 weeks, lander was only for transport to and from DSG. The 6 weeks is hopefully enough time to see how body reacts to 1/6g.

With this concept we are free to explore all moon, rovers have life of years and can travel to new locations 100kms if not 1000s apart between missions. This without all the overheads of developing and supporting lunar base.

NB lander and rovers still need to be developed even if planning lunar base. Non RTG rovers while cheaper would limit range to 1 weeks radius from base.



Offline sevenperforce

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Re: SLS Lander?
« Reply #57 on: 03/16/2018 04:09 pm »
I presume that graphic is talking about Blue Moon and similar initiatives, not a man-rated lander.
Nope.



Someone dusted off the LM truck plans.
What good is a reusable lander unless it can accept propellant transfer or replacement tanks?

ESA had FISO presentation few months back where plan was to have two RTG+Solar powered 2man rovers. These could support crew for up to 6 weeks, lander was only for transport to and from DSG. The 6 weeks is hopefully enough time to see how body reacts to 1/6g.

With this concept we are free to explore all moon, rovers have life of years and can travel to new locations 100kms if not 1000s apart between missions. This without all the overheads of developing and supporting lunar base.

NB lander and rovers still need to be developed even if planning lunar base. Non RTG rovers while cheaper would limit range to 1 weeks radius from base.
Whatever solution is reached, the rover needs to be able to autonomously drive to and dock with the lander, so that your EVA solution doesn't have to be carried up and down by the ascent vehicle.

If I was designing a reusable moon ferry, I'd do a single-stage drop tank design with four engines (to allow engine-out survival) with high clearance legs and a docking adapter placed underneath or off to one side. New tanks would be dropped in with each new mission.

Offline TrevorMonty

Re: SLS Lander?
« Reply #58 on: 03/16/2018 04:24 pm »
Not sure how crew get from lander to rover. Docking is ideal, but landers height may not allow this. Crew could step onto roof of rover and enter from top, avoids dust from ground. Would avoid need for heavy bulky EVA suits. NB Pod access EVAs would already be on rovers.


Offline sevenperforce

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Re: SLS Lander?
« Reply #59 on: 03/16/2018 04:54 pm »
Not sure how crew get from lander to rover. Docking is ideal, but landers height may not allow this. Crew could step onto roof of rover and enter from top, avoids dust from ground. Would avoid need for heavy bulky EVA suits. NB Pod access EVAs would already be on rovers.
How about going more skycrane-style? Something like this (see attachments).

Reusable space truck is a platform with 4-6 drop tanks around the perimeter, a payload adapter underneath, and multiple engines mounted around the perimeter. It can be used to deliver virtually any payload (high capacity when used expendable; lower capacity when used reusable). It can also accept a crew vehicle attached to the aft payload adapter, holding the vehicle just above the surface and allowing plenty of clearance for a rover to drive up and dock.

It drops unneeded tanks in the order they are emptied during descent and ascent but retains all other hardware. It is sized to be able to deliver a crew vehicle to the surface and bring it back up to lunar orbit with about half a reserve tank remaining.

You would need something like a Canadarm at a station to replace the drop tanks with new articles after each sortie.

Offline Caleb Cattuzzo

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Re: SLS Lander?
« Reply #60 on: 03/16/2018 08:08 pm »
Not sure how crew get from lander to rover. Docking is ideal, but landers height may not allow this. Crew could step onto roof of rover and enter from top, avoids dust from ground. Would avoid need for heavy bulky EVA suits. NB Pod access EVAs would already be on rovers.
How about going more skycrane-style? Something like this (see attachments).

Reusable space truck is a platform with 4-6 drop tanks around the perimeter, a payload adapter underneath, and multiple engines mounted around the perimeter. It can be used to deliver virtually any payload (high capacity when used expendable; lower capacity when used reusable). It can also accept a crew vehicle attached to the aft payload adapter, holding the vehicle just above the surface and allowing plenty of clearance for a rover to drive up and dock.

It drops unneeded tanks in the order they are emptied during descent and ascent but retains all other hardware. It is sized to be able to deliver a crew vehicle to the surface and bring it back up to lunar orbit with about half a reserve tank remaining.

You would need something like a Canadarm at a station to replace the drop tanks with new articles after each sortie.

DSG (or whatever they are calling the lunar station now) was supposed to have a canadarm on it but I don't know if it has changed
« Last Edit: 03/16/2018 08:08 pm by Caleb Cattuzzo »
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Offline A_M_Swallow

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Re: SLS Lander?
« Reply #61 on: 03/16/2018 08:09 pm »
Not sure how crew get from lander to rover. Docking is ideal, but landers height may not allow this. Crew could step onto roof of rover and enter from top, avoids dust from ground. Would avoid need for heavy bulky EVA suits. NB Pod access EVAs would already be on rovers.



There are no bridges on the Moon so rovers are not height constrained.

Offline speedevil

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Re: SLS Lander?
« Reply #62 on: 03/16/2018 08:12 pm »
There are no bridges on the Moon so rovers are not height constrained.
Centre of gravity is still an issue, plus crew area structural weight goes (more or less) with pressurised volume.

Offline A_M_Swallow

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Re: SLS Lander?
« Reply #63 on: 03/16/2018 08:14 pm »
There are no bridges on the Moon so rovers are not height constrained.
Centre of gravity is still an issue, plus crew area structural weight goes (more or less) with pressurised volume.

Yes but height is a standard problem for trucks.

Offline sevenperforce

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Re: SLS Lander?
« Reply #64 on: 03/17/2018 11:17 am »
Reusable space truck: platform with 4-6 drop tanks around the perimeter, a payload adapter underneath, and multiple engines mounted around the perimeter. It can be used to deliver virtually any payload (high capacity when used expendable; lower capacity when used reusable). It can also accept a crew vehicle attached to the aft payload adapter, holding the vehicle just above the surface and allowing plenty of clearance for a rover to drive up and dock.

It drops unneeded tanks in the order they are emptied during descent and ascent but retains all other hardware. It is sized to be able to deliver a crew vehicle to the surface and bring it back up to lunar orbit with about half a reserve tank remaining.

You would need something like a Canadarm at a station to replace the drop tanks with new articles after each sortie.
DSG (or whatever they are calling the lunar station now) was supposed to have a canadarm on it but I don't know if it has changed
If so, that makes things pretty straightforward. The Moon Truck and a resupply ship both dock to the DSG, and the Canadarm removes any remaining empties from the Truck, then replaces them with full tanks from the resupply ship. Canadarm can also mate payloads to the adapter on the Truck. Downmass (rovers, habs, telescopes, etc.) can be quite high, since the dry mass of the Truck that needs to come back to lunar orbit is just legs, engines, RCS, and some structure.

If the Truck can notionally take 5 tonnes down to the lunar surface and back up again, it should be able to take substantially more downmass one-way, and even more if it is used expendable at end of life.

The ideal propulsion would be electric pump-fed storable, I believe.
« Last Edit: 03/17/2018 11:18 am by sevenperforce »

 

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