Lockheed-Martin's re-usable Lunar Lander for LOP-G

[AeroGav]

So,   NASA recently proposed the "Lunar Gateway" station as a payload for their SLS expendable megarocket,  which has been under development in some form for the past 30 years,  but is finally expected to fly within the next 2 - 3.

In turn , Lockheed have used this as an opportunity to reveal their design for a re-usable lander,  capable of  ferrying astronauts from the lunar gateway to the moon's surface and back.

Scott Manley simulated this vessel in KSP, with a few realism add-ons :

 

 

Whereas Apollo used separate Ascent and Descent stages,  a re-usable vessel needs to do the whole round trip in a single stage,  and this seems to be a problem.    Despite using Hydrolox ,  the mass ratio is miserable,  40 tons of propellant for one ton of payload delivered to the surface.   If all 40 tons of propellant have to be shipped from Earth  to Lunar orbit via expendable SLS rockets,  I can't see re-using the lander working out any cheaper than a disposable design that needs less fuel (total mass shipped from earth) per trip.

I'd appreciate feedback on that point,   but my real question is,   is there any possibility to IRSU oxygen from the lunar regolith , and how would that change the economics of this vehicle's operation ?

The long term goal of lunar exploration is to find water ice that can be split into hydrogen and oxygen,  but it is only thought to exist in permanently shaded craters near the poles.   An extensive prospecting operation needs to be conducted first,  then we need to set up a base with remotely located solar panels bringing power for our ice mining operation.    Volatile and light elements are rare on moon, which has no atmosphere,  magnetic field or strong gravity to help it retain such things,  and the surface heats to several hundred degrees in the daytime.

 If you just want oxygen though, that should be much easier.  The moon is 40% oxygen, by mass,  most of it consisting of various metal oxides and silicates.   Would it not be much easier to extract oxygen from these oxides  (smelting metal ore in a solar furnace?) which exist practically anywhere,    From what i understand,   the  LOX component of hydrolox propellant weighs 7 times as much as the LH2 itself.     So,  even if we still have to bring all the hydrogen for the ascent down to the surface with us,  the ability to refill LOX will greatly improve the amount of payload that can be carried per trip,  and  if only liquid hydrogen has to be brought up from earth,   that's far fewer SLS refuelling trips needed for our lunar propellant depot, per trip to the surface.  Win/Win.

Finally,  if you've got unlimited oxygen,   would there be any point playing with the fuel air ratio of the engine?    I understand hydrogen rich gives better ISP and more stoich gives better thrust -  in these unique conditions,  would it even make sense to lift off from the lunar surface at a slightly oxygen rich ratio,  gradually getting richer as time goes on (need for high thrust getting less, also KSP teaches us to burn our low ISP fuels first? )

Anyone know how the exhaust flame would look ?   The Space Shuttle  main engines ran only slightly rich of stoichiometric ,  and had an almost invisible, white flame.      Hydrolox upper stages tend to run richer, and produce these beautiful blue colours ..

 

[Bill Phil]

The 1 ton payload is likely a limitation brought on from having to support astronauts for a few weeks. The majority of the actual payload is taken up by the equipment and other stuff for the astronauts. Taking that out and using most of the propellant to land would increase payload markedly. A few vehicles might be needed to land equipment down, and then once they can refuel on the surface you can launch them back into orbit to be reused. 

40 tons of propellant? That probably means a 4 ton empty tank. Making some estimates it should be able to carry something on the order of 10 tons throughout the round trip. Most of that is likely equipment for a manned mission. If it has the thrust then it could definitely deliver more payload if it doesn't need to take off again. Taking this and using it to land equipment for a moon base could eventually lead to a decent architecture.

[DerekL1963]

9 hours ago, AeroGav said:

my real question is,   is there any possibility to IRSU oxygen from the lunar regolith , and how would that change the economics of this vehicle's operation ?

In theory, it's possible to use ISRU produced oxygen.  In practice...  you're talking some pretty heavy R&D (expensive) and a fair amount of heavy machinery.  (The more often you're planning on flying, the more machinery you'll need.)  That's not going to be cheap - so you'll likely need a significant number of flights before your amortized costs drop below the cost of terrestrial supplied oxygen.  That's setting aside the ongoing costs of operations, maintenance, and support.  There's also the increased risk due to loss of guaranteed return.

It's all a bit handwavey because nobody is certain if we can even do it...  But either way, it won't be cheap and it likely won't make sense unless you're flying a lot of landing missions.

And there's another catch - without a specialized tanker (read:more money) you're largely limited to landing only at the refueling station...

[magnemoe]

An lunar SSTO only makes sense if you either refuel on surface or you has an cheap way to get fuel to Moon orbit, that is cheaper than the lander.
Only prospect for this is BFR or an large moon base, even with new Glenn it would probably not be cost effective as you would need to throw away multiple upper stages. 

Note that the Lunar gateway is in high orbit around the moon not low and the lander has to get up and down. 

Reuse only makes sense if you save money doing so. it tend to be harder and harder who farther you get from earth and it rarely make sense if you don't reuse all the way. 

Now an two stage lander with reuse of upper stage makes more sense as the upper stage has to return to the gateway station anyway so refueling it and connect it with an new landing stage for an new mission should work. You could also use an crashing stage like an standard upper stage docked to lander, you would need legs and more dV on lander but can probably use something more like an upper stage for most of the landing. Downside is that you could not use an mission specified lander stage.

[AeroGav]

I did a bit of reading around,  and used some rocket equation numbers from this site  - it's a nice little online calculator that saves you from having to understand the math,  you just plug in any three of the four relevant variables, and it calculates the one you left blank

• ISP
• Delta V
• Starting Mass
• Ending Mass

 

http://www.quantumg.net/rocketeq.html

Apparently, the best ISP for hydrolox engines comes when you burn 4.8 tons of LOX for every ton of Hydrogen.  The space shuttle main engine ran less rich at 6 tons of LOX per ton of H2,  and gave up a percent or two ISP for a less bulky and draggy LH2 tank as a result.    Stoich is 8 to 1.    The RL-10 engine has experimentally been run as lean as 13:1 , and did not take any damage.  Apparently, it's all in the boundary layer cooling, if cool enough, the engine is protected  even if the boundary layer itself is lean.   Variants of the RL-10 are capable of adjusting mixture ratio in flight and this was done on later Apollo missions,  though not to such an extreme degree.

https://yarchive.net/space/rocket/fuels/fuel_ratio.html

So, if the lander weighs 19T empty and needs 2500dv to go from the surface to LOP-G,   it will use 14.5 tons propellant for the ascent.     I ran the calcs for 6:1 (SSME ratio) and got 2.07T LH2 and 12.4T LOX.

Not having to carry that ascent oxygen all the way from the lunar gateway is potentially another 12.4t payload , or if we're only carrying 1T down,  then it only has to depart the gateway with 18.9T of fuel instead of tanks brimmed to 42T.       Of course,  that assumes you're topping off the oxygen tanks at the lunar gateway as well as on the surface, which you probably wouldn't do.   

If the lander gets all its oxygen from the surface facility and all its hydrogen from earth,   then basically each tank is having to go the full 5000dv between replenishments, and our mass and payload ratios go back to the starting point -  1 ton of payload for 42 tons fuel used per trip.

However,  at 6:1 fuel ratio,  that means we're shipping only 6 tons of propellant from Earth  (Falcon Heavy in Re-usable mode?) instead of 42 (expendable SLS block b?)

As regards to the process of extracting oxygen from regolith,  https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090018064.pdf

Molten oxide electrolysis looks the lowest risk  - basically melt the lunar soil, then electrolyse it to separate gaseous oxygen,  and you end up with molten metals (mostly silicon and aluminum, some iron) as a byproduct.

It looks like this process can scale down to pretty small sizes, but to make the amounts of oxygen this monster lander needs would take substantial plant - or a lot of time.   Given the putative SLS launch cadence of once every 2 years  however,  maybe that's not such a big deal.

As for what @DerekL1963 said, yes  ISRU is only useful to repeat visits to the same place.   As I understand it, the plan is to prospect the moon with robotic rovers,  then send manned missions to investigate any promising sites they uncover.  So,  that makes it sound like we'll not be doing repeat manned missions to the same spot , until such a time as a full base is established with lunar ice ISRU.      Or will we ?   If Ice is proving elusive,  does there come a point where we just go with this setup to tide us over ? 

Or after finding a promising crater, is there going to be a substantial period of time before a base is established and ice harvesting gets going - perhaps several manned missions would be needed by base architects, and a multitude of  cargo missions while the base is actually constructed.    This kind of operation could make those flights considerably more efficient.

 

[kerbiloid]

2 hours ago, AeroGav said:

then electrolyse it to separate gaseous oxygen

By electrodes?

Melting points:
Iron oxides 1377°...1566°C.
Silicon dioxide 1710°C
Titanium dioxide 1843°C.
Aluminium oxide 2072°C.
Magnesium oxide 2852°C.

[AeroGav]

16 minutes ago, kerbiloid said:

By electrodes?

Melting points:
Iron oxides 1377°...1566°C.
Silicon dioxide 1710°C
Titanium dioxide 1843°C.
Aluminium oxide 2072°C.
Magnesium oxide 2852°C.

According to the powerpoint i linked, they used temperature of 1600, and electrodes of iridium and molybdenum.     The regolith has a composition  of 47% Silicon dioxide,  17.8% Aluminum dioxide,  10% iron oxide.

I think they were only bothered about reducing the iron ore,  the rest can be thrown away.  It's not like there is a shortage of Regolith on the Moon.. 

I'm noticing a pattern of naysayers which is fine, valid objections, but knocking something down is easy.  If you think this is a daft idea,  what do you propose we do instead?  Is it any less plausible than a lunar gateway station,  a reusable 62 ton lander, all supplied entirely from earth via the SLS ?   

[kerbiloid]

Quote

Iridium based anodes and molybdenum based cathodes have survived repeated 8 hour laboratory Molten Regolith Electrolysis cycles.

But how much oxygen has been produced per kilogram of the electrodes while they were intact?

I can see

Quote

Benchmark goal 1 metric ton Oxygen per year

Are they going to spend three sets of Ir/Mo electrodes per day to get 1 t of oxygen per year (i.e. spend a set of 10 cm² thick Ir/Mo electrodes per 1 kg of oxygen)?

Edited October 10, 2018 by kerbiloid

[AeroGav]

Quote

 Iridium based anodes and molybdenum based cathodes have survived repeated 8 hour laboratory Molten Regolith Electrolysis cycles.

Alright,  they seem to be avoiding making any direct claim of performance in the manner you describe.       

I don't know what your background in chemistry is,  i don't work in a relevant field and only have my schoolboy chemistry to fall back on.   I just know this has been touted as the ISRU process that is to take place on the moon, long before water electrolysis was mooted, since there are doubts about finding water ice, in sufficient quantity, concentration and sufficiently close to the surface,  to be amenable to in -situ utilization.     I presume those proposing oxygen extraction from regolith knew what they were talking about and weren't just trying to con gullible politicians for funding.

Obviously the technology is not mature.... but it seems worthy of further development.   I mean,  if Orion and SLS are considered worthy of funding,   so is this ?  Or do you have some expertise in the field so you can say it is a waste of time ?

Again,  can you make your position clear on this ?  Do you think this type of ISRU is a good idea ? a bad idea? or do you have no opinion?

What about lunar ice ISRU?

If you're not keen on this approach, what is your vision for space exploration - i presume you have one,  given that you play KSP....

[wumpus]

6 hours ago, magnemoe said:

An lunar SSTO only makes sense if you either refuel on surface or you has an cheap way to get fuel to Moon orbit, that is cheaper than the lander.
Only prospect for this is BFR or an large moon base, even with new Glenn it would probably not be cost effective as you would need to throw away multiple upper stages.

One thing that SSTO plans help show is how spectacularly useless the Lunar Gateway orbit is.  I thought there might be some excuse to not stage descent stages, but the Lunar Gateway orbit pretty much kills any chances they might have.

delta-v KSC to Lunar Gateway: 12660 m/s
delta-v Lunar Gateway to Lunar surface and back: 4820 m/s

Is that orbit supposed to help for Mars (or just be absolutely useless for anything not the SLS)?  L2 would be where you put a general purpose "gateway" (I suspect the delta-v from L2 to the Moon might not be too bad, but I'd be impressed if you could convince NASA heads of this; don't even look at who heads Congressional science committees).
 

[kerbiloid]

13 minutes ago, AeroGav said:

Again,  can you make your position clear on this ?  Do you think this type of ISRU is a good idea ? a bad idea? or do you have no opinion?

I think that Moon is a piece of useless slag at the very bottom of energetical well.
It consists of most heatproof compounds in the universe, and any attempt to split them into something useful looses the sense when you have the Earth resources and industry right near the Moon

It costs ~100 MJ/kg to deliver anything from the Earth, so nothing energetically compatible makes sense.
It costs ~100 MJ/kg to deliver anything from the Earth, so nothing requiring delivering of expendables makes sense..

When people will get fusion and be swimming in oceans of cheap energy, it will be possible to split regolith into atoms with pure electromagnetism, but at the same moment this will not make sense from practical point of view.

Edited October 10, 2018 by kerbiloid

[YNM]

17 minutes ago, AeroGav said:

what is your vision for space exploration

Titan.

[AeroGav]

18 minutes ago, kerbiloid said:

I think that Moon is a piece of useless slag at the very bottom of energetical well.
It consists of most heatproof compounds in the universe, and any attempt to split them into something useful looses the sense when you have the Earth resources and industry right near the Moon

It costs ~100 MJ/kg to deliver anything from the Earth, so nothing energetically compatible makes sense.
It costs ~100 MJ/kg to deliver anything from the Earth, so nothing requiring delivering of expendables makes sense..

When people will get fusion and be swimming in oceans of cheap energy, it will be possible to split regolith into atoms with pure electromagnetism, but at the same moment this will not make sense from practical point of view.

Then what do you think about Phobos and Deimos ?  Better ?  

[kerbiloid]

7 minutes ago, AeroGav said:

Then what do you think about Phobos and Deimos ?  Better ?  

Better only because nothing better around. They have low-G, Mars aside for fluids, but all equipment should be being delivered from Earth.

So, appropriate as a part of Mars-Phobos industrial infrastructure. But colonization also makes no sense.
Just a refuel station, a plant for mass production of carbon and nitrogen -rich materials for asteroids, a backup warehouse to resurrect the devastated Earth industry,  a place to keep building near-solar emitters and keep launching  them to the near-Sun orbit where they should be a swarm of direct power transmitters.

No colonies, but several tens kilohumans as engineers and technicians working on contracts.

Edited October 10, 2018 by kerbiloid

[NSEP]

22 hours ago, AeroGav said:

Anyone know how the exhaust flame would look ?   The Space Shuttle  main engines ran only slightly rich of stoichiometric ,  and had an almost invisible, white flame.      Hydrolox upper stages tend to run richer, and produce these beautiful blue colours ..

 

The engines on the lander likely to be RL10s (the engine in the picture you posted below) but it probably isn't going to be blue in color, but rather, be almost invisible. 

(Skip to 4:20) This is what the RL10 looks like running in space, from an Atlas V rocket.

[KG3]

11 hours ago, AeroGav said:

According to the powerpoint i linked, they used temperature of 1600, and electrodes of iridium and molybdenum.     The regolith has a composition  of 47% Silicon dioxide,  17.8% Aluminum dioxide,  10% iron oxide.

I think they were only bothered about reducing the iron ore,  the rest can be thrown away.  It's not like there is a shortage of Regolith on the Moon.. 

17.8% Aluminum dioxide...  The space shuttle solid rocket booster's fuel was about 16% aluminum.  Is there any chance that a solid rocket fuel of some kind could be made mostly from Moon regolith?  You would need an oxidizer too like ammonium perchlorate   NH₄ClO₄  so you would need some ingredients like chlorine, nitrogen and maybe some hydrogen but you would have the aluminum, oxygen and that little pinch of iron covered.  

[StrandedonEarth]

48 minutes ago, KG3 said:

17.8% Aluminum dioxide...  The space shuttle solid rocket booster's fuel was about 16% aluminum.  Is there any chance that a solid rocket fuel of some kind could be made mostly from Moon regolith?  You would need an oxidizer too like ammonium perchlorate   NH₄ClO₄  so you would need some ingredients like chlorine, nitrogen and maybe some hydrogen but you would have the aluminum, oxygen and that little pinch of iron covered.  

I’m given to understand that there’s plenty of perchlorates in the Martian regolith. Maybe that could be an export product for a Martian colony 

A bit of a long lead supply line though 

[qzgy]

56 minutes ago, StrandedonEarth said:

I’m given to understand that there’s plenty of perchlorates in the Martian regolith. Maybe that could be an export product for a Martian colony 

A bit of a long lead supply line though  

Shipping costs would be enormous too.

[DerekL1963]

2 hours ago, KG3 said:

17.8% Aluminum dioxide...  The space shuttle solid rocket booster's fuel was about 16% aluminum.  Is there any chance that a solid rocket fuel of some kind could be made mostly from Moon regolith?  You would need an oxidizer too like ammonium perchlorate   NH₄ClO₄  so you would need some ingredients like chlorine, nitrogen and maybe some hydrogen but you would have the aluminum, oxygen and that little pinch of iron covered.  

You need carbon for the PBAN too....  Quite a bit of it.