Author Topic: Cislunar Transporter, what do we know?  (Read 30534 times)

Offline DrHeywoodFloyd

Cislunar Transporter, what do we know?
« on: 05/21/2023 12:38 pm »
A Key part of the Blue Origin wining proposal is the the Lockheed Martin "CIS Lunar Transporter"... what do we know about it?

There is only a very brief mention of it on the Lockheed site:
https://news.lockheedmartin.com/2023-05-19-Lockheed-Martin-on-Blue-Origins-National-Team-Selected-to-Develop-Human-Lunar-Lander

Is there somewhere where will be able to find out more about this critical piece of space infrastructure... ? Can we read the details of what Lockheed Martin submitted as part of their response

It appears that it will be a very significant re-usable piece of technology as it will be used to shuttle back and forth fuel, food and other resources between the Earth and the moon transferring fuel for Blue Moon manned lander from earth orbit to the lander... here is a study by Airbus for something equivalent...

https://www.militaryaerospace.com/commercial-aerospace/article/14231970/airbus-cltv-moon-cruiser

One thing I noticed is that Lockheed and Blue Origin are both part of the DARPA DRACO program...

https://spacenews.com/darpa-selects-blue-origin-lockheed-martin-to-develop-spacecraft-for-nuclear-propulsion-demo/

Could they be using this technology for the CIS Lunar Transporter from Artemis V from 2029? As it appears that DRACO will launch  about 2027...
https://wccftech.com/nasas-nuclear-engine-will-generated-10000-pounds-of-thrust-launch-in-2027/

« Last Edit: 06/05/2023 11:32 pm by gongora »

Offline joek

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Re: CIS Lunar Transporter, what do we know?
« Reply #1 on: 05/21/2023 01:07 pm »
A Key part of the Blue Origin wining proposal is the the Lockheed Martin "CIS Lunar Transporter"... what do we know about it?

There is only a very brief mention of it on the Lockheed site:
https://news.lockheedmartin.com/2023-05-19-Lockheed-Martin-on-Blue-Origins-National-Team-Selected-to-Develop-Human-Lunar-Lander

It appears that it will be a very significant piece of technology as it will be used to shuttle back and forth between the Eart and the moon transferring fuel for Blue Moon manned lander from earth orbit to the lander.

Is there somewhere where will be able to find out more about this critical piece of space infrastructure... ?

Don't think we can draw any conclusions at this point. It's a piece of the team's HLS proposal, not a separately identifiable entity; per the press release "...which will provide a refueling and servicing spacecraft..." Whether it can stand alone (or has a market as a separate entity) is another question.

Quote
One thing I noticed is that Lockheed and Blue Origin are both part of the DARPA DRACO program...

https://spacenews.com/darpa-selects-blue-origin-lockheed-martin-to-develop-spacecraft-for-nuclear-propulsion-demo/

Could they be using this technology for the CIS Lunar Transporter from Artemis V from 2029? As it appears that DRACO will launch  about 2027...
https://wccftech.com/nasas-nuclear-engine-will-generated-10000-pounds-of-thrust-launch-in-2027/

Interesting, but doubtful has much relationship to HLS. HLS has enough on its plate without NTR. Give it a few years (or more likely decades).

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #2 on: 05/21/2023 05:08 pm »
Transporter will use Hydrolox whether it is BE7 or RL10 engines we don't know.

One of benefits of Blue design is development of cryocooler to keep LH2 cool long term. This  will also be useful for NTR as they use LH2. Blue spokesman stated this.
« Last Edit: 05/22/2023 04:19 pm by zubenelgenubi »

Offline GWH

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Offline GWH

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Re: CIS Lunar Transporter, what do we know?
« Reply #4 on: 05/21/2023 07:58 pm »
One of the few things we do know is that Blue's lunar VP said everything will launch on New Glenn.

I would really love to know anything and everything about this.  Since a large capacity tug/tanker/whatever else it is could open up so many possibilities. Everything from alternative means to get cargo to Gateway, large cargo to reusable landers, to crew transportation via commercial capsule derivatives or even Orion.  It has the potential to replace almost everything that SLS does, and is in my opinion one of the larger game changers (in addition to Starship) for cis-lunar development.

In my opinion it's a bigger deal than the lander since you can't build a more capable lander without propellant depots/tankers.
« Last Edit: 05/21/2023 08:05 pm by GWH »

Offline GWH

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Re: CIS Lunar Transporter, what do we know?
« Reply #5 on: 05/21/2023 08:19 pm »
In regards to storage and FUTURE capabilities (ie not for HLS) Blue's press release sums up the storage capabilities:

https://www.blueorigin.com/news/nasa-selects-blue-origin-for-mission-to-moon/

Quote
Under this contract, Blue Origin and its National Team partners will develop and fly both a lunar lander that can make a precision landing anywhere on the Moon’s surface and a cislunar transporter.
These vehicles are powered by LOX-LH2. The high-specific impulse of LOX-LH2 provides a dramatic advantage for high-energy deep space missions. Nevertheless, lower performing but more easily storable propellants (such as hydrazine and nitrogen tetroxide as used on the Apollo lunar landers) have been favored for these missions because of the problematic boil-off of LOX-LH2 during their long mission timelines. Through this contract, we will move the state of the art forward by making high-performance LOX-LH2 a storable propellant combination. Under SLD, we will develop and fly solar-powered 20-degree Kelvin cryocoolers and the other technologies required to prevent LOX-LH2 boil-off. Future missions beyond the Moon, and enabling capabilities such as high-performance nuclear thermal propulsion, will benefit greatly from storable LH2. Blue Origin’s architecture also prepares for that future day when lunar ice can be used to manufacture LOX and LH2 propellants on the Moon.
« Last Edit: 05/21/2023 08:21 pm by GWH »

Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #6 on: 05/21/2023 09:10 pm »
One of the few things we do know is that Blue's lunar VP said everything will launch on New Glenn.

I would really love to know anything and everything about this.  Since a large capacity tug/tanker/whatever else it is could open up so many possibilities. Everything from alternative means to get cargo to Gateway, large cargo to reusable landers, to crew transportation via commercial capsule derivatives or even Orion.  It has the potential to replace almost everything that SLS does, and is in my opinion one of the larger game changers (in addition to Starship) for cis-lunar development.

In my opinion it's a bigger deal than the lander since you can't build a more capable lander without propellant depots/tankers.

Agreed... the CISLunar Transporter ultimately is THE BIGGER deal than the lander and makes a economic sustainable lunar eco-system in the next six + plus years from now..the lander is merely a connector from the gateway and back...the CISLunar Transporter turns it into a profitable business model ....and I posit that Blue is thinking strategic with this, and that means [I am spit balling here..and guessing where they are going with this...]:

1. The CISLunar Transport will be re-usable, and not one off.

2. In the mid-term to long term.. Launching SLS rocket to the lunar gateway will not be sustainable... when you can shuttle, fuel, food, and other resources, and perhaps even people via a more economic and sustainable CISLunar Transporter... by that stage NASA would be more interesting in using SLS for other space exploration projects... whereas Blue is clearly looking to set up infrastructure that it can build upon, and most importantly CHARGE service and transportation fees... that is how they will make this venture profitable.

3. Once the CISLunar Transporter deliver its goods to the Lunar Gateway, that means there is an empty transporter going back to Earth that Blue can use to return cargo [Mining? High value Minerals? ] back to Earth...

4. Whilst the connector to the Moon will be the Lunar Gateway, I posit that CISLunar Transport would return to that warehouse in Earth orbit... Blue's Orbital Reef to pick up the consolidated cargo in terms of fuel, food, people [including Dr Heywood Floyd going to Clavius Base... because they have found something that has been deliberately buried!! ] going out to the Moon, and receive the cargo coming back.... and you can bet the Blue and it's partners are going to CHARGE warehousing, service and transport fees [no doubt this this cargo will be launched via New Glenn, and returned via a Jarvis ...]

I am sure this is the strategic plan for Blue Origin in the mid term.... that is 8-10 years from now....  because utimately this Moon enterprise is all about logistics and you can bet Blue and its partners are going to provide the hardware at near cost to NASA... but make a profit on the service fees.

Ultimately I suspect Blue intends to use the hydrogen from the water that it has mined in the Moon to provide fuel for the CISLunar Transporter, and I posit that it will be a Nuclear Thermal Rocket in about 10-20 years from now.... because of the greater Isp... I only hope they ensure they have plenty of AE-35 units in stock on the moon.... just in case!

« Last Edit: 05/21/2023 09:18 pm by DrHeywoodFloyd »

Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #7 on: 05/23/2023 01:26 am »
Why would the cislunar transporter choose NTR? ...which is far more expensive (including launch) than hydrolox...
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Offline trimeta

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Re: CIS Lunar Transporter, what do we know?
« Reply #8 on: 05/23/2023 01:50 am »
Why would the cislunar transporter choose NTR? ...which is far more expensive (including launch) than hydrolox...
Because DrHeywoodFloyd is obsessed with NTR.

Re: CIS Lunar Transporter, what do we know?
« Reply #9 on: 05/23/2023 01:53 am »
Why would the cislunar transporter choose NTR? ...which is far more expensive (including launch) than hydrolox...

yeah, far more likely they just go with a BE-3U, or BE-7 cluster. RL-10 is an option I guess, but are those few seconds of ISP worth it for an engine that likely costs more? Idk. At the same time, if you want to reuse this thing over and over and over upfront cost might not be such a huge deal.
« Last Edit: 05/23/2023 01:54 am by spacenuance »

Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #10 on: 05/23/2023 05:39 am »
Why would the cislunar transporter choose NTR? ...which is far more expensive (including launch) than hydrolox...
Because DrHeywoodFloyd is obsessed with NTR.

Absolutely, because, consider NERVA...
Specific impulse, vacuum   841 seconds (8.25 km/s)
[ https://en.wikipedia.org/wiki/NERVA ]

As a reference, consider Raptor...
Specific impulse, vacuum   363 s (3.56 km/s)
[ https://en.wikipedia.org/wiki/SpaceX_Raptor]


That means I get twice the bang for my buck with a NTR than with the corresponding chemical rocket, which means I can move twice the amount of cargo to and from the moon, than if I was using a corresponding chemical rocket.

I do agree the first iteration of the cis lunar transporter in the short term 7-10 years will be a chemical rocket, but beyond 10+ years...Blue Origin are strongly hinting with this their intentions...

"....Future missions beyond the Moon, and enabling capabilities such as high-performance nuclear thermal propulsion, will benefit greatly from storable LH2. Blue Origin’s architecture also prepares for that future day when lunar ice can be used to manufacture LOX and LH2 propellants on the Moon...."

[ https://www.blueorigin.com/news/nasa-selects-blue-origin-for-mission-to-moon/ ]

It is no co-incidence that Lockheed Martin and Blue Origin are developing DRACO with General Atomics [what a name!]...

DRACO (Demonstration Rocket for Agile Cislunar Operations): https://www.eoportal.org/satellite-missions/draco ... sound familiar????!!
And...
https://www.darpa.mil/news-events/2021-04-12
https://spacenews.com/darpa-selects-blue-origin-lockheed-martin-to-develop-spacecraft-for-nuclear-propulsion-demo/

Why? Because it is in the name of "Blue Origin".... NASA mission is to explore space; Blue Origin mission is to move out from the Earth and make money out of space... earn a profit...because if they intend to put a million people living and working inn space...it will not be out of generosity... but a whole financial ecosystem.. they have to make a profit... using the resources on the moon to build out in LEO makes sense [ because of the smaller gravitational well around the moon when compare to the earth], and having a NTR means they can move more resources from the moon to low earth orbit that would be used in the construction of large space stations, such as the O'Neill cylinder [ https://tinyurl.com/j2rl79x]. And in fact Bezos has made reference to this when he unveiled Blue moon…

https://www.nbcnews.com/think/opinion/jeff-bezos-blue-origin-space-colony-dreams-ignore-plight-millions-ncna1006026

That is why this cis lunar transporter is a really, really important deal, because with this, this is how Blue Origin makes this a reality; and cis lunar transporter with nuclear thermal rocket engines is really the only effective transporter than help them attain this. This is probably 20+ years from now.

This start to make sense of Jeff Bezos statement that he is not interested in LEO… because it is the Moon is where he starts to build the infrastructure for space stations such as the O'Neill cylinder. LEO for him with orbital Reef will be a depot, and a transit hub for mission out to the moon, where fuel, food and other resources will be consolidated as cargo for onward shipment to the moon... as As General Omar Bradley famously said: “Amateurs talk strategy. Professionals talk logistics.” The cis lunar transporter is all about logistics, and moving cargo to and from the moon... including spare AE-35 units that some damn astronauts managed to bust!! I hope they have completed the necessary forms!

PS: The other reason why I want a cis lunar nuclear transporter…. Because I do not get stuck for hours trying to figure out the instructions for the space toilet… https://tinyurl.com/2kpfwc37 !!















« Last Edit: 05/23/2023 05:51 am by DrHeywoodFloyd »

Offline GWH

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Re: CIS Lunar Transporter, what do we know?
« Reply #11 on: 05/23/2023 06:26 am »
The OP should just start a new thread on Blue and NTR if that's going to be the focus, or rename it.

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #12 on: 05/23/2023 07:42 am »
First, a spelling quibble:  It's "cislunar."  "Cis" is not an acronym; it's a latin prefix meaning "on this side", so cislunar space is the space roughly inside the Moon's orbit.  (We will immediately have trouble with this definition with L2, but just go with it...)

The OP should just start a new thread on Blue and NTR if that's going to be the focus, or rename it.

We need a thread for this.  This one will do just fine.  Let's not create more.

A little calculatin':

If we assume that the BE-7 has Isp=450s, then a 16t dry mass needs 41.8t of prop to do NRHO-LS(polar)-NRHO.  Figure 45t for equatorial access.  (That's a guess.)

If you can develop a Cislunar Transport (CT--gotta have an acronym) with a structural mass coefficient of about 8% (considerably better than Centaur V, which is about 10%), assume an RL10CX Isp=458s, and a delta-v budget of about 3300m/s to do LEO-BLT-NRHO-RPOD (which might be a little optimistic), and then another 3300m/s to return propulsively to LEO, then you can deliver 45t of prop to NRHO for 135t of prop to LEO, which should be 3 New Glenn launches.

First issue:  Doing NRHO-LEOpropulsive costs 13t of prop.  You can reduce that substantially if you're willing to aerobrake from TEI back into LEO.  If your vehicle can handle about 30m/s of delta-v per pass, it'll aerobrake back in a couple of months.  That would make the margins a lot better for everything.

My first thought when I heard that LockMart was providing this thing was that they're for-sure buying ULA (i.e., buying out Boeing's share), using the Centaur V as the basis for the CT, stretching it, and throwing all the ACES stuff at it that Boeing didn't want to do.  Since it could launch dry, it would easily fit on a Vulcan Centaur VC6, maybe even a VC4.

But there are a few problems with this theory:

1) John Coulouris (sp?) said explicitly that the CT would launch on a New Glenn.

2) Stretching Centaur V from 54t of prop to 135t is... a stretch.  Even if you widened it to 6.3m (NG's last known static envelope diameter), it still doesn't fit in the NG fairing.  And mounting it on a PAF is really hard.

3) They could put a C5 variant in as a third stage to NG, but that's a lot of work, likely requires structural work to the NG stage 2, and will mess up their GSE.  New Glenn has enough problems without heaping those kinds of requirements on it.

So this doesn't seem right.

Next thought:  It could be an NG S2 variant.  But:

1) LockMart would hate that.  They're gonna want to go into the orbital prop business big-time, and the last thing they want is to be completely dependent on Blue technology.

2) If I were them, I'd want to build something that could support Orion in case SLS goes belly-up. Adapting Orion to launch on a Falcon Heavy, a New Glenn, or (if you squint) a VC6+, should be relatively straightforward.  But then you still need to get it to NRHO.

In other words, they'd need something a lot like the Constellation Earth Departure Stage, and the CT should be able to fill the bill.  The easiest way to do that is to dock the Orion nose-to-nose with the CT, which results in "eyeballs out" acceleration for the crew, with them hanging from their straps.  That's probably OK at 3m/s², but a quick back-of-napkin for a single BE-3U at 50% throttle gave a burnout acceleration of something like 18m/s².  Getting humans to perform dangling from straps at almost 2gee doesn't sound viable.

3) It'd be really easy to take something that fit into an NG fairing and make it work with Starship, if the biz relationship or technology went south on them.  But that thing won't be an NG variant; Blue would never stand for it.

So I think it's a new vehicle.  It may be based on a lot of C5 tech (RL10CX, ACES tech, same avionics, same RCS, kinda the same thrust structure), but it needs new tanks.

I won't bore you with my algebra, and I don't claim this is optimal, because I didn't want to do the calculus to model the NG fairing's ogive and do the optimization problem, but picking a known spot on the ogive, which was in the 2018 New Glenn PUG (again, really stale), I came up with something that seemed to work.  From the PAF, working upward:

1) LH2 tank:  6.3m wide by 8.5m tall.  19.1t of LH2.

2) LOX tank:  5.5m wide by 4.2m tall.  113.9t of LOX.
Total prop capacity:  133t.

3) Some kind of shelf for non-hydrolox consumables, and maybe unpressurized payload.

4) Thrust structure, engine, and engine bell.  Note that the whole vehicle is basically upside-down.

Note that I'm using O:F mixture = 3.9 5.9 [typo].  I think there are a few extra tonnes with a bit more optimization, but we're in the ballpark.

This is... not a C5.  Indeed, in some respects it looks more like a DCSS, in that you'd probably have the LOX tank suspended from a frustum-like thrust structure, which would transmit thrust from the engines directly to the LH2 tank.  But I suspect that you could use a lot of C5 manufacturing tech to build something like this.

The thing launches empty, so the most difficult structural load will be supporting the upside-down engine/thrust structure way up in the nose of the fairing.  It's possible that this is a non-starter, because the center of mass will be quite high.  But you can pressure-stabilize the hell out of this thing for launch.

I think it's essential that the Blue Moon be able to be completely fueled in a single RPOD/prop transfer operation.  Just like Starship, accidents in LEO are accidents between dumb components at low energy, and they're fairly easily fixed.  Accidents in NRHO, which involve crew-rated hardware, are a disaster.  So if you can reduce the number of RPODs/transfers from 3 to 1, you've done some serious risk reduction.  You've also made a more efficient system, with a better mass ratio.

But that requires some fancy footwork to get everything to fit in the NG fairing.

That's as far as I've gotten.
« Last Edit: 05/23/2023 07:48 am by TheRadicalModerate »

Offline warp99

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Re: CIS Lunar Transporter, what do we know?
« Reply #13 on: 05/23/2023 12:07 pm »
First, a spelling quibble:  It's "cislunar."  "Cis" is not an acronym; it's a latin prefix meaning "on this side", so cislunar space is the space roughly inside the Moon's orbit.  (We will immediately have trouble with this definition with L2, but just go with it...)

A little calculatin':

If we assume that the BE-7 has Isp=450s, then a 16t dry mass needs 41.8t of prop to do NRHO-LS(polar)-NRHO.  Figure 45t for equatorial access.  (That's a guess.)

If you can develop a Cislunar Transport (CT--gotta have an acronym) with a structural mass coefficient of about 8% (considerably better than Centaur V, which is about 10%), assume an RL10CX Isp=458s, and a delta-v budget of about 3300m/s to do LEO-BLT-NRHO-RPOD (which might be a little optimistic), and then another 3300m/s to return propulsively to LEO, then you can deliver 45t of prop to NRHO for 135t of prop to LEO, which should be 3 New Glenn launches.

First issue:  Doing NRHO-LEOpropulsive costs 13t of prop.  You can reduce that substantially if you're willing to aerobrake from TEI back into LEO.  If your vehicle can handle about 30m/s of delta-v per pass, it'll aerobrake back in a couple of months.  That would make the margins a lot better for everything.

My first thought when I heard that LockMart was providing this thing was that they're for-sure buying ULA (i.e., buying out Boeing's share), using the Centaur V as the basis for the CT, stretching it, and throwing all the ACES stuff at it that Boeing didn't want to do.  Since it could launch dry, it would easily fit on a Vulcan Centaur VC6, maybe even a VC4.

But there are a few problems with this theory:

1) John Coulouris (sp?) said explicitly that the CT would launch on a New Glenn.

2) Stretching Centaur V from 54t of prop to 135t is... a stretch.  Even if you widened it to 6.3m (NG's last known static envelope diameter), it still doesn't fit in the NG fairing.  And mounting it on a PAF is really hard.

3) They could put a C5 variant in as a third stage to NG, but that's a lot of work, likely requires structural work to the NG stage 2, and will mess up their GSE.  New Glenn has enough problems without heaping those kinds of requirements on it.

So this doesn't seem right.

Next thought:  It could be an NG S2 variant.  But:

1) LockMart would hate that.  They're gonna want to go into the orbital prop business big-time, and the last thing they want is to be completely dependent on Blue technology.

2) If I were them, I'd want to build something that could support Orion in case SLS goes belly-up. Adapting Orion to launch on a Falcon Heavy, a New Glenn, or (if you squint) a VC6+, should be relatively straightforward.  But then you still need to get it to NRHO.

In other words, they'd need something a lot like the Constellation Earth Departure Stage, and the CT should be able to fill the bill.  The easiest way to do that is to dock the Orion nose-to-nose with the CT, which results in "eyeballs out" acceleration for the crew, with them hanging from their straps.  That's probably OK at 3m/s², but a quick back-of-napkin for a single BE-3U at 50% throttle gave a burnout acceleration of something like 18m/s².  Getting humans to perform dangling from straps at almost 2gee doesn't sound viable.

3) It'd be really easy to take something that fit into an NG fairing and make it work with Starship, if the biz relationship or technology went south on them.  But that thing won't be an NG variant; Blue would never stand for it.

So I think it's a new vehicle.  It may be based on a lot of C5 tech (RL10CX, ACES tech, same avionics, same RCS, kinda the same thrust structure), but it needs new tanks.

I won't bore you with my algebra, and I don't claim this is optimal, because I didn't want to do the calculus to model the NG fairing's ogive and do the optimization problem, but picking a known spot on the ogive, which was in the 2018 New Glenn PUG (again, really stale), I came up with something that seemed to work.  From the PAF, working upward:

1) LH2 tank:  6.3m wide by 8.5m tall.  19.1t of LH2.

2) LOX tank:  5.5m wide by 4.2m tall.  113.9t of LOX.
Total prop capacity:  133t.

3) Some kind of shelf for non-hydrolox consumables, and maybe unpressurized payload.

4) Thrust structure, engine, and engine bell.  Note that the whole vehicle is basically upside-down.

Note that I'm using O:F mixture = 3.9 5.9 [typo].  I think there are a few extra tonnes with a bit more optimization, but we're in the ballpark.

This is... not a C5.  Indeed, in some respects it looks more like a DCSS, in that you'd probably have the LOX tank suspended from a frustum-like thrust structure, which would transmit thrust from the engines directly to the LH2 tank.  But I suspect that you could use a lot of C5 manufacturing tech to build something like this.

The thing launches empty, so the most difficult structural load will be supporting the upside-down engine/thrust structure way up in the nose of the fairing.  It's possible that this is a non-starter, because the center of mass will be quite high.  But you can pressure-stabilize the hell out of this thing for launch.

I think it's essential that the Blue Moon be able to be completely fueled in a single RPOD/prop transfer operation.  Just like Starship, accidents in LEO are accidents between dumb components at low energy, and they're fairly easily fixed.  Accidents in NRHO, which involve crew-rated hardware, are a disaster.  So if you can reduce the number of RPODs/transfers from 3 to 1, you've done some serious risk reduction.  You've also made a more efficient system, with a better mass ratio.

But that requires some fancy footwork to get everything to fit in the NG fairing.

That's as far as I've gotten.

The HLS is said to have a dry mass of 16 tonnes and a wet mass of greater than or equal to 45 tonnes.  It will arrive in NRHO in the "dry" state but not completely or it would have no station keeping ability.  As you say it will launch on New Glenn. 

New Glenn cannot inject the HLS into even a TLI let alone get it to NRHO since it can only lift 13 tonnes to GTO.  The culprit is the massive 7m diameter second stage with a dry mass of 23 tonnes if you back work the drop in payload from 45 tonnes to LEO to 13 tonnes to GTO.  The BE-3U has a relatively low Isp of around 405s due to it being an expander bleed system that dumps the turbine propellant overboard. 

Instead the HLS can launch fully fueled to LEO and then get itself to NRHO since it has a higher Isp of the BE-7 of around 450s as a closed cycle expander and has a lower dry mass than NG S2.  I make it that it arrives with about 3.5 tonnes of propellant but in any case enough for an extended loiter in NRHO. 

The transfer vehicle then launches on New Glenn with say 12 tonnes dry mass and 33 tonnes of propellant.  It gets refueled by a tanker with 45 tonnes of propellant that can just be a slightly stretched NG S2 with refueling probe.  This then allows the transfer vehicle to get to NRHO and transfer 29 tonnes of propellant to the HLS.  This leaves the HLS short by about 1 km/s of the delta V to get to the Lunar surface and back.  The transfer stage stays docked to the HLS to do the initial parts of the landing burn and is then discarded and crashes into the Moon well past the landing site while the HLS completes the rest of the mission. 

The advantage is that only three New Glenn launches are required in total for the first mission and two launches for each subsequent mission.  The disadvantage is that the transfer vehicle is expended on each mission. 

Looking at the case where the architecture is extended so that the transfer vehicle returns to LEO to be refueled the propellant requirement increases to 170 tonnes in LEO with a proportional increase in dry mass to around 20 tonnes.  Now it takes a total of five launches for the HLS and transfer vehicle plus three refueling flights for the first mission and three refueling flights for each subsequent mission.  As each flight requires a massive expendable S2 and fairing the cost structure actually favours expending the transfer vehicle.
« Last Edit: 05/23/2023 12:09 pm by warp99 »

Offline DreamyPickle

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Re: CIS Lunar Transporter, what do we know?
« Reply #14 on: 05/23/2023 12:55 pm »
Many people are very happy that Blue Origin is finally copying SpaceX but one thing they didn't copy is the focus on simplicity.

Why would Blue contract a hydrolox tug to a third party when they're already developing a hydrolox upper stage (project jarvis) and a hydrolox lander (blue moon) all in house?

While SpaceX Star Ship/Super Heavy vehiclesalso have some variation all of them (including the core launcher) are coming off a single production line.

Offline Zed_Noir

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Re: CIS Lunar Transporter, what do we know?
« Reply #15 on: 05/23/2023 01:44 pm »
<snip>
Why would Blue contract a hydrolox tug to a third party when they're already developing a hydrolox upper stage (project jarvis) and a hydrolox lander (blue moon) all in house?
<snip>
Off loading some development work to Lockheed Martin for lobbying support from them.

Also will point out that Below Orbit Blue is already working on many projects. The BE-4, BE-3U & BE-7 engines. The New Glenn launcher, the alternate Clipper upper stage (Jarvis) & the Blue Moon 2 lander.The ground support infrastructure around pad SLC-36 at Canaveral and the Florida manufacturing facility. Plus the nascent Orbital Reef platform and the nearly superfluous New Sheppard.

With the list above. You still think that Below Orbit Blue should developed and pay for another complex spacecraft?

Offline meekGee

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Re: CIS Lunar Transporter, what do we know?
« Reply #16 on: 05/23/2023 03:25 pm »


Why would the cislunar transporter choose NTR? ...which is far more expensive (including launch) than hydrolox...
Because DrHeywoodFloyd is obsessed with NTR.

Absolutely, because, consider NERVA...
Specific impulse, vacuum841 seconds (8.25 km/s)
[ https://en.wikipedia.org/wiki/NERVA ]

As a reference, consider Raptor...
Specific impulse, vacuum363 s (3.56 km/s)
[ https://en.wikipedia.org/wiki/SpaceX_Raptor]


That means I get twice the bang for my buck with a NTR than with the corresponding chemical rocket, which means I can move twice the amount of cargo to and from the moon, than if I was using a corresponding chemical rocket. 

You should do the entire calculation.  Higher ISP reduces the mass of the propellant, but might (and in this case will) increase the dry weight.

So the higher dV the mission, the higher the odds that a high ISP drive will prevail.  And this is not a high dV mission, so the gains, if any, are not large.

Then, factor in complexity and development cost, and you see why nuclear drives are usually discussed for outer planet or fast-Mars-transit missions
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Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #17 on: 05/23/2023 07:30 pm »
Here are some examples of various ISPs  all vehicles start with 150t.
6km/s
900ISP NTR Finish mass 76t
460 ISP 40.8t
380 ISP  30t

4km/s
95.4t
61.8t
51.3t


8km/s
60.6t
25.5t
17.5t

Need to subtract vehicles dry mass from that finish mass to get payload. In case of NTR drymass of reactor +engine will be lot more than the two chemical engines. NTR does have LOX tank.Methalox will have small fuel tanks, LOX tank is same as Hydrolox and doesn't need cryocooler.

Even at 4km/s NTR has extra 44t compared to Metholox. Need subtract NTR extra dry mass from that. NERVA was 18t for 55klbs engine would hope modern version would be lot lighter say 14t compared to 1t for couple RL10s.

Rocket labs Neutron composite methalox US tank is 385kg for 50t. Larger LH2 tanks will be very light especially if they don't need to handle high Gs of launch with fuel.

I'm going guess the NTR will still have extra 25t payload at 4kms. Higher DV more NTR shines..
« Last Edit: 05/23/2023 11:08 pm by zubenelgenubi »

Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #18 on: 05/23/2023 11:16 pm »
Here are some examples of various ISPs  all vehicles start with 150t.
6km/s
900ISP NTR Finish mass 76t
460 ISP 40.8t
380 ISP  30t

4km/s
95.4t
61.8t
51.3t


8km/s
60.6t
25.5t
17.5t

Need to subtract vehicles dry mass from that finish mass to get payload. In case of NTR drymass of reactor +engine will be lot more than the two chemical engines. NTR does have LOX tank.Methalox will have small fuel tanks, LOX tank is same as Hydrolox and doesn't need cryocooler.

Even at 4km/s NTR has extra 44t compared to Metholox. Need subtract NTR extra dry mass from that. NERVA was 18t for 55klbs engine would hope modern version would be lot lighter say 14t compared to 1t for couple RL10s.

Rocket labs Neutron composite methalox US tank is 385kg for 50t. Larger LH2 tanks will be very light especially if they don't need to handle high Gs of launch with fuel.

I'm going guess the NTR will still have extra 25t payload at 4kms. Higher DV more NTR shines..

Excellent analysis! However I do have to pick...
"Need to subtract vehicles dry mass from that finish mass to get payload. In case of NTR drymass of reactor +engine will be lot more than the two chemical engines. NTR does have LOX tank.Methalox will have small fuel tanks, LOX tank is same as Hydrolox and doesn't need cryocooler."

Surely being a Nuclear Thermal engine, and considering only that, it is will not need a LOX tank? Because with NERVA it was all hydrogen.. the reactor was a better heat source than the hydrolox reaction....

Online Asteroza

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Re: CIS Lunar Transporter, what do we know?
« Reply #19 on: 05/24/2023 02:56 am »
Here are some examples of various ISPs  all vehicles start with 150t.
6km/s
900ISP NTR Finish mass 76t
460 ISP 40.8t
380 ISP  30t

4km/s
95.4t
61.8t
51.3t


8km/s
60.6t
25.5t
17.5t

Need to subtract vehicles dry mass from that finish mass to get payload. In case of NTR drymass of reactor +engine will be lot more than the two chemical engines. NTR does have LOX tank.Methalox will have small fuel tanks, LOX tank is same as Hydrolox and doesn't need cryocooler.

Even at 4km/s NTR has extra 44t compared to Metholox. Need subtract NTR extra dry mass from that. NERVA was 18t for 55klbs engine would hope modern version would be lot lighter say 14t compared to 1t for couple RL10s.

Rocket labs Neutron composite methalox US tank is 385kg for 50t. Larger LH2 tanks will be very light especially if they don't need to handle high Gs of launch with fuel.

I'm going guess the NTR will still have extra 25t payload at 4kms. Higher DV more NTR shines..

Excellent analysis! However I do have to pick...
"Need to subtract vehicles dry mass from that finish mass to get payload. In case of NTR drymass of reactor +engine will be lot more than the two chemical engines. NTR does have LOX tank.Methalox will have small fuel tanks, LOX tank is same as Hydrolox and doesn't need cryocooler."

Surely being a Nuclear Thermal engine, and considering only that, it is will not need a LOX tank? Because with NERVA it was all hydrogen.. the reactor was a better heat source than the hydrolox reaction....

I would assume NTR with LOx is a LANTRN setup...

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #20 on: 05/24/2023 03:22 am »
NERVA engine and reactor was 18t for 55klbs thrust. Should be able to shave few tons off that with todays technology. Also have note we are talk V1.0 flight NTR compared to its flight proven Hydrolox competitor RL10 which has had decades to reduce its mass.
At a guess 20-25t for NTR, tanks and cryrocooler.

Methalox vehicle drymass would be in 5-7t range. Does need extra insulation for passive cooling.

Hydrolox drymass is likely be 7-10t due to cryocooler and extra insulation.

For all these vehicle mass of tanks can be reduced as they shouldn't be exposed to high G with lot fuel on board. Fully loaded they are 150t with 25t thrust so 1/6 G. Burnout will be lot higher but can be kept <1G by throttling engines back. By comparison upper stages need to be lot stronger as they are exposed to lot higher Gs and aerodynamic forces.
« Last Edit: 05/24/2023 03:23 am by TrevorMonty »

Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #21 on: 05/24/2023 03:28 am »
If you look at the specs NASA/DARPA were asking for for the NTP demonstrator, the Isp was lower and the T/W ratio much lower than NERVA. I would not expect the first NTP vehicle to get specs even as good as NERVA, as essentially it'll have to be tested in space, not on the ground, so they'll have to sandbag the heck out of it.

Not a chance NTP is on the critical path for the cislunar transporter, if it is related at all.
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Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #22 on: 05/24/2023 03:46 am »
When used as tanker in CISLunar space return trip vehicle only needs to save enough fuel to transport dry mass.  NTR still has significant payload advantage. Here are results for 4km/s delivery trip plus 4km/s return.

ISP  Drymass,  fuel delivered.
900 25t, 56.2t
460 10t, 37.5
380 7t, 30.8

Build cost of chemical is lot cheaper compared to NTR which also needs it reactor refuelled or replaced every so often at $$$.

Where NTR really comes into its own is high DV outer solar system missions. For CIS lunar and Mars chemical should workout cheaper.


Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #23 on: 05/24/2023 03:55 am »
When used as tanker in CISLunar space return trip vehicle only needs to save enough fuel to transport dry mass.  NTR still has significant payload advantage. Here are results for 4km/s delivery trip plus 4km/s return.

ISP  Drymass,  fuel delivered.
900 25t, 56.2t
460 10t, 37.5
380 7t, 30.8

Build cost of chemical is lot cheaper compared to NTR which also needs it reactor refuelled or replaced every so often at $$$.

Where NTR really comes into its own is high DV outer solar system missions. For CIS lunar and Mars chemical should workout cheaper.
Keep in mind that the DARPA DRACO project doesn't even shoot for 900s Isp. The requirement is 700s Isp. And the T/W ratio is even worse.

I think it's quite possible NTR via the DARPA project would have *lower* performance than optimized hydrolox.
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Offline clongton

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Re: CIS Lunar Transporter, what do we know?
« Reply #24 on: 05/24/2023 01:35 pm »
I would assume NTR with LOx is a LANTRN setup...

It's LANTR, not LANTRN (no final "N") LOX-Augmented Nuclear Thermal Rocket (LANTR)
I have ALWAYS been a huge fan of this technology :)
THIS is how we should be doing this.
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Offline Steve G

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Re: CIS Lunar Transporter, what do we know?
« Reply #25 on: 05/24/2023 03:44 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

Offline matthewkantar

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Re: CIS Lunar Transporter, what do we know?
« Reply #26 on: 05/24/2023 04:46 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

Other nukes have been launched since Cassini with little or no protest. The Mars rovers and New Horizons for instance.

Offline whitelancer64

Re: CIS Lunar Transporter, what do we know?
« Reply #27 on: 05/24/2023 05:07 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

Other nukes have been launched since Cassini with little or no protest. The Mars rovers and New Horizons for instance.

There were vocal concerns / protests for all those launches. Much smaller than the protest for Cassini, but the concern is still there.

https://www.nytimes.com/2006/01/16/health/plutonium-on-mission-to-pluto-worries-antinuke-activists.html

https://fair.org/home/applause-for-perseverance-ignores-plutonium-bullet-we-dodged/
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Offline clongton

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Re: CIS Lunar Transporter, what do we know?
« Reply #28 on: 05/24/2023 05:22 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

Other nukes have been launched since Cassini with little or no protest. The Mars rovers and New Horizons for instance.

There were vocal concerns / protests for all those launches. Much smaller than the protest for Cassini, but the concern is still there.

https://www.nytimes.com/2006/01/16/health/plutonium-on-mission-to-pluto-worries-antinuke-activists.html

https://fair.org/home/applause-for-perseverance-ignores-plutonium-bullet-we-dodged/

There will *always* be crazies to protest something, anything. Very little happens these days without someone protesting. Hell I've even seen videos of protesters claiming that Elon Musk was making too many holes in the sky letting our air leak out!  ::)  That's how informed they are. They have a right to protest, so as long as they don't physically get in the way, just ignore them.
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Offline Greg Hullender

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Re: CIS Lunar Transporter, what do we know?
« Reply #29 on: 05/24/2023 05:34 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

Other nukes have been launched since Cassini with little or no protest. The Mars rovers and New Horizons for instance.

There were vocal concerns / protests for all those launches. Much smaller than the protest for Cassini, but the concern is still there.

https://www.nytimes.com/2006/01/16/health/plutonium-on-mission-to-pluto-worries-antinuke-activists.html

https://fair.org/home/applause-for-perseverance-ignores-plutonium-bullet-we-dodged/

There will *always* be crazies to protest something, anything. Very little happens these days without someone protesting. Hell I've even seen videos of protesters claiming that Elon Musk was making too many holes in the sky letting our air leak out!  ::)  That's how informed they are. They have a right to protest, so as long as they don't physically get in the way, just ignore them.
I think the Cassini protests caused a lot of people to reevaluate how safe plutonium is. Surprisingly, the conclusion is that it's not all that dangerous. Ralph Nader stirred a lot of people up over it, and then kept lying about it for his own purposes, but when he never got any support from credible sources, I think most of the energy went out of the movement. It's hard to get favorable press coverage when you won't respond to questions like, "What do you say about the fact that scientists say you're wrong?"

When NASA attempts a launch with an actual reactor, then we'll see what people say. But I suspect protests of it won't get much coverage.
« Last Edit: 05/24/2023 05:44 pm by Greg Hullender »

Offline edzieba

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Re: CIS Lunar Transporter, what do we know?
« Reply #30 on: 05/24/2023 05:41 pm »
The thread seems to have been completely derailed by random discussion of NTRs, when the 'Cislunar Transporter' has already been directly and explicitly confirmed as a Hydrolox vehicle:
In regards to storage and FUTURE capabilities (ie not for HLS) Blue's press release sums up the storage capabilities:

https://www.blueorigin.com/news/nasa-selects-blue-origin-for-mission-to-moon/

Quote
Under this contract, Blue Origin and its National Team partners will develop and fly both a lunar lander that can make a precision landing anywhere on the Moon’s surface and a cislunar transporter.
These vehicles are powered by LOX-LH2. The high-specific impulse of LOX-LH2 provides a dramatic advantage for high-energy deep space missions. Nevertheless, lower performing but more easily storable propellants (such as hydrazine and nitrogen tetroxide as used on the Apollo lunar landers) have been favored for these missions because of the problematic boil-off of LOX-LH2 during their long mission timelines. Through this contract, we will move the state of the art forward by making high-performance LOX-LH2 a storable propellant combination. Under SLD, we will develop and fly solar-powered 20-degree Kelvin cryocoolers and the other technologies required to prevent LOX-LH2 boil-off. Future missions beyond the Moon, and enabling capabilities such as high-performance nuclear thermal propulsion, will benefit greatly from storable LH2. Blue Origin’s architecture also prepares for that future day when lunar ice can be used to manufacture LOX and LH2 propellants on the Moon.
Best to take NTR discussion to one of the many existing threads on the matter.

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #31 on: 05/24/2023 06:12 pm »

Is it more efficient to refuel a transporter in LEO than HEO.?

 Ignoring fact that LEO has lot more reflective heat making keeping fuel cooler more difficult.

Comes down to which is more efficient at transporting fuel between LEO and HEO, RLV heavy US or transporter which is optimized for space. Both tanker and RLV are using same fuel as typically a hydrolox US will be used to deliver fuel to hydrolox transporter.




Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #32 on: 05/24/2023 06:17 pm »
It’s best to do it at both ends…
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Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #33 on: 05/24/2023 09:38 pm »
How would the nuclear fuel be launched and deployed? I recall when Cassini was being launched the massive protests against the plutonium, even though the RTGs were rated to survive an LV explosion, but I imagine there would be a lot more radioactive mass being launched to support the nuclear rocket.

According to this they will be using HALEU, and not  plutonium…

https://www.darpa.mil/news-events/2023-01-24

What is HALEU? HALEU is uranium that has been enriched so that the concentration of the fissile isotope U-235 is between 5 and 20 percent of the mass of the fuel. This is higher than the 3 to 5 percent U-235 concentration, or “assay,” of Low-Enriched Uranium that fuels the existing fleet of light water reactors.

https://www.energy.gov/ne/articles/what-high-assay-low-enriched-uranium-haleu

The fuel in the reactor will not be enriched to bomb grade as it was with the SNAP10a reactor, which was the last real reactor launched into space, almost 60 years ago!!
https://en.wikipedia.org/wiki/SNAP-10A

PS: I would like to someone change the discussion back to what exactly Lockheed Martin Will be building as the initial cislunar transporter [CT] in the short-term. The questions I have for us to consider:
1. What would be the dimensions of this CT?
2. As the primary mission of CT Will be to transport fuel from LEO to Lunar orbit:
a. What would be the mass of hydrogen that it will need to transport for HLS operations?
b. What would be the mass of oxygen that it will need to transport for HLS operations?
c. What do we think would be the launch cadence to and from LEO to the Moon and back?
3. I am positing that Blue will use Orbital Reef so outgoing cargo [ie fuel etc] can be consolidated in orbit while the CT is off on a transport mission to the Moon, what adaptations would they need on Orbital Reef so it can perform this task?

Offline joek

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Re: CIS Lunar Transporter, what do we know?
« Reply #34 on: 05/24/2023 09:53 pm »
PS: I would like to someone change the discussion back to what exactly Lockheed Martin Will be building as the initial cislunar transporter [CT] in the short-term. The questions I have for us to consider:
1. What would be the dimensions of this CT?
2. As the primary mission of CT Will be to transport fuel from LEO to Lunar orbit:
a. What would be the mass of hydrogen that it will need to transport for HLS operations?
b. What would be the mass of oxygen that it will need to transport for HLS operations?
c. What do we think would be the launch cadence to and from LEO to the Moon and back?
3. I am positing that Blue will use Orbital Reef so outgoing cargo [ie fuel etc] can be consolidated in orbit while the CT is off on a transport mission to the Moon, what adaptations would they need on Orbital Reef so it can perform this task?

Agree. NTR et. al. are not in scope for CIS Lunar Transporter.
1. What would be the dimensions of this CT?
Unknown at present, but can probably be derived from propellant mass requirements for each HLS mission.
2. As the primary mission of CT Will be to transport fuel from LEO to Lunar orbit:
a. What would be the mass of hydrogen that it will need to transport for HLS operations?
See #1.
b. What would be the mass of oxygen that it will need to transport for HLS operations?
See #1. Plus maybe a bit extra Ox for ECLSS
c. What do we think would be the launch cadence to and from LEO to the Moon and back?
Similar cadence as HLS missions.
3. I am positing that Blue will use Orbital Reef so outgoing cargo [ie fuel etc] can be consolidated in orbit while the CT is off on a transport mission to the Moon, what adaptations would they need on Orbital Reef so it can perform this task?
Bad assumption and a digression. Maybe Orbital Reef has a play at some point in the future, but not for HLS. Take that discussion elsewhere please.

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #35 on: 05/24/2023 10:29 pm »
Blue lander needs around 45t of fuel to do round trip from gateway.
Going need 3x NG tanker launches to full tanker in LEO. The cryocooler will add extra mass but allows for longer lower DV trip to gateway. Also needs enough fuel for return trip to LEO.

NB transfer point may not be LEO, SpaceX is using HEO for SS. Higher the orbit less fuel RLV can deliver. On plus side DV to Gateway is lower also cryocooler is working in cooler enviroment. There is lot of reflective heat from Earth in LEO.

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #36 on: 05/24/2023 10:39 pm »
The HLS is said to have a dry mass of 16 tonnes and a wet mass of greater than or equal to 45 tonnes.  It will arrive in NRHO in the "dry" state but not completely or it would have no station keeping ability.  As you say it will launch on New Glenn. 

New Glenn cannot inject the HLS into even a TLI let alone get it to NRHO since it can only lift 13 tonnes to GTO.  The culprit is the massive 7m diameter second stage with a dry mass of 23 tonnes if you back work the drop in payload from 45 tonnes to LEO to 13 tonnes to GTO.  The BE-3U has a relatively low Isp of around 405s due to it being an expander bleed system that dumps the turbine propellant overboard.

Do you have good numbers on the NG S2 size?  Mine are extremely stale and of questionable provenance.  The best ones I've found are from ZachF's post back in 2021.:

Isp = 445s (considerably more optimistic than yours)
O:F = 4.65:1
Dry Mass = 16.7t
Prop Mass = 175t

That would make ε = dry/(dry+prop) = 8.7%, which is a plausible number.  If these are right, this is a much bigger stage than I thought.

Quote
Instead the HLS can launch fully fueled to LEO and then get itself to NRHO since it has a higher Isp of the BE-7 of around 450s as a closed cycle expander and has a lower dry mass than NG S2.  I make it that it arrives with about 3.5 tonnes of propellant but in any case enough for an extended loiter in NRHO. 

Yes, there should be no problem sending the Blue Moon to NRHO from LEO under its own power, as long as it can be launched with enough hydrolox to make its wet mass 45t.

The big question is how big the BM tanks are.  Here are some possibilities:

Worst case: NRHO-LS(equatorial)-NRHO on its own:  prop = 46.4t, wet mass = 62.4t.
It does NRHO-LS(polar)-NRHO all on its own: prop = 41.8t, wet mass = 57.8t.
It has a reusable TE to take it to LLO: prop = 32.8t, wet mass = 48.8t.
It has a TE crasher to take it to sub-LLO: prop = 29.0t, wet mass = 45.0t.

All of these are consistent with Coulouris's "wet mass is north of 45t" statement.

I've attached my calculations for these four scenarios below, which include the Cislunar Transports required to service them.  Not exactly user-friendly, but you should get the gist.

Quote
The transfer vehicle then launches on New Glenn with say 12 tonnes dry mass and 33 tonnes of propellant.  It gets refueled by a tanker with 45 tonnes of propellant that can just be a slightly stretched NG S2 with refueling probe.  This then allows the transfer vehicle to get to NRHO and transfer 29 tonnes of propellant to the HLS.  This leaves the HLS short by about 1 km/s of the delta V to get to the Lunar surface and back.  The transfer stage stays docked to the HLS to do the initial parts of the landing burn and is then discarded and crashes into the Moon well past the landing site while the HLS completes the rest of the mission. 

The advantage is that only three New Glenn launches are required in total for the first mission and two launches for each subsequent mission.  The disadvantage is that the transfer vehicle is expended on each mission. 

I think this sounds like a fine plan, especially since the NG S2 is currently an expendable stage anyway.  Might as well crash it on the Moon as crash it in the ocean. 

However, it doesn't appear to be what they're doing.  Coulouris explicitly stated that the Cislunar Transport was a LockMart product/service, to be launched on a New Glenn. 

I suppose this doesn't rule out the possibility of it being some add-on kit to the NG S2, but it seems really unlikely.  If LockMart wants to build this, they're gonna want to use it for a variety of missions, and they're gonna want to launch it on a VC4 in addition to NG.  Given their position in the military payload biz, I'd expect them to want full control over this thing, with plans to use it for on-orbit servicing.  It would also allow them to bid on parts of DRACO, if that actually happens. That's likely a pretty good business model.

Quote
Looking at the case where the architecture is extended so that the transfer vehicle returns to LEO to be refueled the propellant requirement increases to 170 tonnes in LEO with a proportional increase in dry mass to around 20 tonnes.  Now it takes a total of five launches for the HLS and transfer vehicle plus three refueling flights for the first mission and three refueling flights for each subsequent mission.  As each flight requires a massive expendable S2 and fairing the cost structure actually favours expending the transfer vehicle.

You can do better than that if you're willing to aerobrake from TEI back into LEO.  If your vehicle can handle the heat pulse generated by a 20m/s aerobrake pass, getting from TEI to LEO takes less than 80days, which is more than adequate for their purposes.  From NRHO to some kind of reverse BLT (I think that should be a real thing), probably isn't more than 250m/s.  From LLO, I suspect it's better just to use regular TEI numbers (about 1030m/s, I think).

Update:  Fixed a problem in the reusable TE case.
« Last Edit: 05/25/2023 03:18 am by TheRadicalModerate »

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #37 on: 05/24/2023 11:41 pm »
Drymass of 10% for TE is very high. F9 US is 5% and it needs to handle lot higher forces ie launch Gs, aerodynamic, and mass of payload plus fairing.
TE will be launched in fairing and can be empty to reduces forces. Once in orbit the only forces it has to deal with is thrust from 1-2 RL10s or BE7s. Tanks should be ultra light weight. Cryocooler and its solar panels will be thing that adds extra mass. NB solar panels actually do double duty as sun shades.

Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #38 on: 05/24/2023 11:57 pm »
Drymass of 10% for TE is very high. F9 US is 5% and it needs to handle lot higher forces ie launch Gs, aerodynamic, and mass of payload plus fairing.
TE will be launched in fairing and can be empty to reduces forces. Once in orbit the only forces it has to deal with is thrust from 1-2 RL10s or BE7s. Tanks should be ultra light weight. Cryocooler and its solar panels will be thing that adds extra mass. NB solar panels actually do double duty as sun shades.
Nope, 10% dry mass is actually very good for a hydrolox stage. The forces of launch are actually fairly small compared to the internal pressure forces. dual-engine centaur has about 11% dry mass, and it's an extremely mass efficient balloon tank. Hydrolox has a very low bulk density compared to kerolox, especially subcooled kerolox like Falcon 9. less than half. So you'd expect the dry mass to be twice as much as a kerolox one. (And keep in mind Merlin has the best T/W ratio of any rocket engine ever...)

10% is actually uber-optimistic as a mass fraction for a hydrolox upper stage, especially if it has a docking port or additional insulation or active cryocooler or is reusable or has 6 axis control or whatever. 15-20% is more likely.
« Last Edit: 05/24/2023 11:59 pm by Robotbeat »
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Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #39 on: 05/26/2023 04:55 am »
I think it's pretty important to be able to do the fueling of the Blue Moon with only one CT flight:  LEO - BLT - NRHO - RPOD - reverseBLT - LEOaerobrake.  My rationale is that you want to minimize RPOD and refueling risks to the crew-rated hardware as much as possible.

But the price of doing this is that you need a fairly exotic payload structure in the New Glenn fairing to have LOX and LH2 tanks that can hold the ~116t of prop that are needed.

If LockMart (again assuming a ULA purchase) just stretched a Centaur V from 54t of prop to 64t, you could do a refueling for an equatorial mission in two trips.  I think that only requires about a 1.3m stretch.  But it's two trips.

Online Asteroza

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Re: CIS Lunar Transporter, what do we know?
« Reply #40 on: 05/26/2023 05:26 am »
Dumb Transporter question;

I would assume the baseline is LEO delivery by New Glenn, but is Lockheed beholden to Blue Origin for LEO delivery per se?
Especially if you launched it mostly empty?

Tankers to fill Transporter are essentially fungible as long as you have a solar powered cryocooler onboard the Transporter.
So, as long as you can RPOD a tanker vehicle to it, they could accept propellant deliveries from anyone.
Someone could even cheat and launch a water tanker and an electrolysis unit in theory, as long as you have the time to waste cracking water.

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #41 on: 05/26/2023 07:05 am »
Dumb Transporter question;

I would assume the baseline is LEO delivery by New Glenn, but is Lockheed beholden to Blue Origin for LEO delivery per se?
Especially if you launched it mostly empty?

Tankers to fill Transporter are essentially fungible as long as you have a solar powered cryocooler onboard the Transporter.
So, as long as you can RPOD a tanker vehicle to it, they could accept propellant deliveries from anyone.
Someone could even cheat and launch a water tanker and an electrolysis unit in theory, as long as you have the time to waste cracking water.
Read old paper on LEO depot that converted water to Hydrolox. LEO wasn't great location, only had sunlight for just over half time and reflective heat from earth made it harder for cryocoolers.

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #42 on: 05/26/2023 10:11 am »

Someone could even cheat and launch a water tanker and an electrolysis unit in theory, as long as you have the time to waste cracking water.
Put the solar-thermal cracking unit on the depot, and launch/transport/store the water in its solid phase until split.

Offline tea monster

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Re: CIS Lunar Transporter, what do we know?
« Reply #43 on: 05/26/2023 10:31 am »
Isn't the whole point of storing it as water that you don't have the cryogenic storage and subsequent boil-off and leak problems that you would have with liquid hydrogen?

The water could be sent up as a block of ice and just chuck a sunshade onto the tanker module.  Subsequent thawing out of the ice to water and then cracking it might be a lot less effort than keeping a full-time cryogenic storage facility running out at  the Gateway.

EDIT: Having a system to convert ice to fuel would be good practice for doing the same procedure on the surface of the moon with lunar ice. Eventually, when the lunar transport system matures, you could even supply the Gateway fuel depot with ice from the surface of the moon.
« Last Edit: 05/26/2023 10:35 am by tea monster »

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #44 on: 05/26/2023 12:26 pm »
Isn't the whole point of storing it as water that you don't have the cryogenic storage and subsequent boil-off and leak problems that you would have with liquid hydrogen?

The water could be sent up as a block of ice and just chuck a sunshade onto the tanker module.  Subsequent thawing out of the ice to water and then cracking it might be a lot less effort than keeping a full-time cryogenic storage facility running out at  the Gateway.

EDIT: Having a system to convert ice to fuel would be good practice for doing the same procedure on the surface of the moon with lunar ice. Eventually, when the lunar transport system matures, you could even supply the Gateway fuel depot with ice from the surface of the moon.
If transporting water from LEO to Gateway still need a couple fuel launches to fuel tanker so it deliver water.

Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #45 on: 05/26/2023 12:31 pm »
Dumb Transporter question;

I would assume the baseline is LEO delivery by New Glenn, but is Lockheed beholden to Blue Origin for LEO delivery per se?
Especially if you launched it mostly empty?

Tankers to fill Transporter are essentially fungible as long as you have a solar powered cryocooler onboard the Transporter.
So, as long as you can RPOD a tanker vehicle to it, they could accept propellant deliveries from anyone.
Someone could even cheat and launch a water tanker and an electrolysis unit in theory, as long as you have the time to waste cracking water.
Read old paper on LEO depot that converted water to Hydrolox. LEO wasn't great location, only had sunlight for just over half time and reflective heat from earth made it harder for cryocoolers.

Would you be able to provide a link concerning "... Read old paper on LEO depot that converted water to Hydrolox..."

Surely it would not be cost effective to ship water up to LEO, and have to crack it into. it's component hydrogen and oxygen, because of the volumes involved? I would posit it would need huge solar arrays, that approx 50% of the time will not be generating electricity as depot would pass behind the Earth... I would posit that as the NG second stage is using BE-3U that use LOX and LH2, then logically it would be better transport up LH2 and LOX, but with bigger tanks... as for whether there would be a need for a cryocooler in LEO I would say not as posit that there would many resupply missions and so some boil off may be acceptable because the level of reflective heat coming from the Earth as was stated previously by another poster.

Offline tbellman

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Re: CIS Lunar Transporter, what do we know?
« Reply #46 on: 05/26/2023 03:04 pm »
Surely it would not be cost effective to ship water up to LEO, and have to crack it into. it's component hydrogen and oxygen, because of the volumes involved? I would posit it would need huge solar arrays, that approx 50% of the time will not be generating electricity as depot would pass behind the Earth... I would posit that as the NG second stage is using BE-3U that use LOX and LH2, then logically it would be better transport up LH2 and LOX, but with bigger tanks...

Indeed.  A hypotetical 100% efficient electrolyser needs 142 MJ per kilogram of hydrogen produced, but real-world electrolysers need around 180 MJ/kg or more.

If we go by TheRadicalModerate's estimate of 116 tonnes of hydrolox needed, and assume a 1:6 ratio (by mass) between hydrogen and oxygen needed (roughly typical for hydrolox rocket engines), that would require 3 TJ, or 830 MWh.  Allow half a year for electrolysing that, and assume you are in sunlight 67% of the time, and you would need 280 kW from your solar panels.  That's way more than what ISS has, for comparison.

And this with somewhat optimistic assumptions.

Note also that ~1:6 ratio between hydrogen and oxygen that engines want.  The output from the electrolysis is in a ration of 1:8.  This means that you will be lifting some 25-30% more mass than if you lifted hydrolox in the wanted ratio, or ~149 tonnes instead of ~116 tonnes.

Offline RDMM2081

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Re: CIS Lunar Transporter, what do we know?
« Reply #47 on: 05/26/2023 04:35 pm »
This is a very fun thread to daydream about. Can I just add how excited I am for the CT.  It sounds like quite possibly the first true "Space Ship". At least the first one which, at least theoretically, is intended to be reused in space indefinitely. Picturing this thing making multiple trips between LEO and NRHO for fueling runs just tickles all the SciFi bits for me.  Will be very fun to watch it evolve, and hear about the mission dynamics, conops, engineering trades, capabilities, and finally watch it fly!

Online TrevorMonty

Re: CIS Lunar Transporter, what do we know?
« Reply #48 on: 05/26/2023 06:13 pm »
Surely it would not be cost effective to ship water up to LEO, and have to crack it into. it's component hydrogen and oxygen, because of the volumes involved? I would posit it would need huge solar arrays, that approx 50% of the time will not be generating electricity as depot would pass behind the Earth... I would posit that as the NG second stage is using BE-3U that use LOX and LH2, then logically it would be better transport up LH2 and LOX, but with bigger tanks...

Indeed.  A hypotetical 100% efficient electrolyser needs 142 MJ per kilogram of hydrogen produced, but real-world electrolysers need around 180 MJ/kg or more.

If we go by TheRadicalModerate's estimate of 116 tonnes of hydrolox needed, and assume a 1:6 ratio (by mass) between hydrogen and oxygen needed (roughly typical for hydrolox rocket engines), that would require 3 TJ, or 830 MWh.  Allow half a year for electrolysing that, and assume you are in sunlight 67% of the time, and you would need 280 kW from your solar panels.  That's way more than what ISS has, for comparison.

And this with somewhat optimistic assumptions.

Note also that ~1:6 ratio between hydrogen and oxygen that engines want.  The output from the electrolysis is in a ration of 1:8.  This means that you will be lifting some 25-30% more mass than if you lifted hydrolox in the wanted ratio, or ~149 tonnes instead of ~116 tonnes.
If we get to stage that lunar Hydrolox is cheap enough to supply LEO, there would still be case for launching LH2 to use up surplus LOX.


Offline punder

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Re: CIS Lunar Transporter, what do we know?
« Reply #49 on: 05/26/2023 06:25 pm »
If we get to stage that lunar Hydrolox is cheap enough to supply LEO, there would still be case for launching LH2 to use up surplus LOX.
Or sell it to others as propellant, chemical feedstock, etc.

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #50 on: 05/26/2023 07:59 pm »
Surely it would not be cost effective to ship water up to LEO, and have to crack it into. it's component hydrogen and oxygen, because of the volumes involved?
Water is denser than hydrogen and oxygen.
Quote
I would posit it would need huge solar arrays, that approx 50% of the time will not be generating electricity as depot would pass behind the Earth...
and that's a problem because?
Depots tend to have nothing *but* time




Indeed.  A hypotetical 100% efficient electrolyser needs 142 MJ per kilogram of hydrogen produced, but real-world electrolysers need around 180 MJ/kg or more.

I did say solar thermal, not solar-electric, but yes, it still needs a lot of sunlight.
[/quote]
Quote
and assume a 1:6 ratio (by mass) between hydrogen and oxygen needed (roughly typical for hydrolox rocket engines),
Or let's not.

If you can think of no other uses for the oxygen in orbit, design the engine to burn the propellant stoichiometrically, and take the performance hit, which is far less than the hit for discarding the extra oxygen.

Quote
that would require 3 TJ, or 830 MWh.  Allow half a year for electrolysing that, and assume you are in sunlight 67% of the time, and you would need 280 kW from your solar panels.  That's way more than what ISS has, for comparison.
It needs around half the collection area for thermal than electric, and luckily Mylar parabolas are cheap and lightweight.

The biggest advantage, is solid water is both inert and sloshless.  A minor one  is at some future point in time ice mining may stop being a sci-fi trope.

I wish I could take the credit for the idea, but it's all NASA's, having the Mars Gateway supplied with water by commercial cargo providers;

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #51 on: 05/26/2023 09:59 pm »
So here's a different, possibly stupid, architecture:  What if you launched the CT "bus", with the propulsion/thrust structure, avionics, IVF¹-like stuff, RCS, and a few hundred m/s worth of delta-v, and then launched a set (or sets) of dumb tanks to mate with it?

I blundered into this one thinking about how you get a really high capacity CT launched with the engine bells taking up lots of volume, which would have been much better used for LH2 tanks.  The only solution to that problem I could think of was to launch the whole CT upside-down, which I think probably violates the center-of-mass height limitation for almost any launcher out there, and almost certainly adds a bunch of tank stringer mass to stiffen the the tanks to support launch stresses coming from the thrust structure vibrating at the top.

But if you launch the bus and the tanks separately, none of those structural things is a problem.  You also get the following very nice properties:

1) You can make the tanks in several different sizes, to suit mission requirements.  120t-capacity tanks for Blue Moon launch easily on a New Glenn.  If you have a nuke you're servicing, you can make the biggest possible LH2 tank you want.  If you're building a GEO satellite servicer, you can make smaller tanks to enhance maneuverability, and you can put grappling and servicing payloads on the top of the tanks.  Same thing for Blue Moon non-hydrolox consumables and deployable payloads.

2) A tank that doesn't have to support managing vibrations from the bus needs less pressure-stabilization, which makes it thinner and lighter.  There's some minimum pressure that the RL10 or BE-7 impellers need to avoid cavitation, but that pressure is almost certainly lower than what you need to get an integrated vehicle to survive launch.  And thrust loads for the CT in space are very small.

3) If you have a common docking and prop transfer interface, the CT can pop the tank off the bus and it can be berthed to the Blue Moon, reducing risk.  (This obviously assumes an arm on the Gateway.)

4) You could stack tanks together.  This might obviate the need for New Glenn to implement refueling at all:  It could just launch a pre-filled tank, dock it to either the bus or a previously-launched tank, and it's done.  It's not like you need giant downcomers to run a 50kN-100kN hydrolox engine.  It's not the most dry-mass-efficient architecture, but the way the numbers are working out, the CT has about 15t of extra wet mass to play with before it risks needing more than 3 NG launches.  If modular architecture costs a couple extra tonnes, things should still close.  And if the tanks are cheap to make, the CT could just discard them and go back to LEO propulsively.

5) If you want reusable tanks, modularity might make aerobraking easier.  If the CT pops the tanks off, the tanks can aerobrake easily, while the bus itself can do a propulsive braking back into LEO for a tiny amount of prop.  That would improve the CT duty cycle, if they get enough demand that the duty cycle needs improving.

6) If you ever do build a lunar hydrolox operation (by launching water off the Moon and electrolyzing it in NRHO), then the ability to pop tanks on and off makes the logistics a lot cleaner.  And you could build a tank variant with enough shielding to make aerobraking a full tank into LEO easy.

7) And the ever-present political angle, in hopes of finding an acceptable way to kill SLS:  You know who knows how to make hydrolox tanks pretty well?  Boeing.²

Note that there's nothing that requires that you launch the bus and the tanks separately; if they fit easily, no problem.  But if you need huge tanks, you can easily launch the bus separately on almost any commercial medium-lifter.
__________
¹Integrated Vehicle Fluids, the key technology package for ACES, and the thing they mostly didn't implement for Centaur V.  There was a hydrolox-fueled internal combustion engine that powered a wide variety of accessories, including a cryocooler, pressurized gaseous H2/O2 for thrusters, ullage pressurization, a generator to charge batteries or directly power stuff, etc.  Once again, I'm assuming that LockMart buys ULA.

²And they hardly ever drop LOX domes!

Offline deadman1204

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Re: CIS Lunar Transporter, what do we know?
« Reply #52 on: 05/27/2023 12:57 am »
Water ice has a larger volume than liquid ice. So storing it as ice is not ideal.
As well, your not gonna be cracking it as a solid. That makes it to difficult to handle.
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.

Offline Hug

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Re: CIS Lunar Transporter, what do we know?
« Reply #53 on: 05/28/2023 02:54 am »
Looking at the case where the architecture is extended so that the transfer vehicle returns to LEO to be refueled the propellant requirement increases to 170 tonnes in LEO with a proportional increase in dry mass to around 20 tonnes.

Now those are some interesting numbers, because that's around about what is expected for New Glenn Second Stage. Obviously the numbers have a bit of play given your stated 23 ton dry mass, but these numbers are getting to the point where it's not easy to fit in the fairing; it's the size of the second stage itself.

So Lunar Clipper is Blue's reusable Glenn hydrogen upper stage that they want to send to the Moon. The theoretical mass of Cislunar Transporter lines up with what you would roughly expect* of Lunar Clipper and Lunar Clipper would be suited to fill this role. It also doesn't really make sense for Blue and Lockheed to develop these two systems simultaneously (assuming that Lunar Clipper is still happening) because it would be borderline redundant for Blue. And like, how much pertinent experience does Lockheed have with large aerobreaking ZBO hydrogen stages that Blue won't have spades more of?

But why would they declare it's Lockheed project if it is so much Blue underneath? And here I have to go borderline conspiracy theory; Blue don't want to handle discussion of that program yet so they hid under a Lockheed umbrella. I mean they still have yet to officially announce even Clipper. Or maybe it's more of a derivation or alternate version + program setup makes it look good to NASA to have Lockheed lead the separate element?

*A little bit on the low side; but you could underfill it + margin.

Next thought:  It could be an NG S2 variant.  But:

1) LockMart would hate that.  They're gonna want to go into the orbital prop business big-time, and the last thing they want is to be completely dependent on Blue technology.
To this I would say that Blue is prime and spending like $4 billions (min) of Bezos money on this, I would imagine Bezos wants the majority of that to stay within his own company. And it's their architecture to decide not Lockheed's. I mean hell they appear to be doing a lot of the crew cabin work now as well.

Now I am biased, because this is what I thought it would be before the announcement; so I could just be letting cope blind me. But I think it's reasonable.
« Last Edit: 05/28/2023 02:56 am by Hug »

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #54 on: 05/28/2023 03:29 am »
Next thought:  It could be an NG S2 variant.  But:

1) LockMart would hate that.  They're gonna want to go into the orbital prop business big-time, and the last thing they want is to be completely dependent on Blue technology.
To this I would say that Blue is prime and spending like $4 billions (min) of Bezos money on this, I would imagine Bezos wants the majority of that to stay within his own company. And it's their architecture to decide not Lockheed's. I mean hell they appear to be doing a lot of the crew cabin work now as well.

Now I am biased, because this is what I thought it would be before the announcement; so I could just be letting cope blind me. But I think it's reasonable.

Blue's pretty much obligated to build what they bid, and the bid says that LockMart is building the CT.  Jeff's now in a position where he has to execute, or it's all over.  If LockMart can take that engineering off his plate, he'll be happy to let them.

Now, I wouldn't be incredibly surprised if LockMart (presumably) gobbling up ULA was only the first step.  The BE-4 deal is a thorn in both Blue's and ULA's side, and the thorn will be transferred to LockMart if they do indeed eat ULA.  So a Blue/LockMart Space merger/acquisition/spinoff/what-have-you isn't beyond the realm of possibility.

But long before any subsequent merger, I think Tory's been hot to trot on doing ACES for real for a while, and I think he's talked LockMart into believing it's a good idea.  That's a lot of tech that Blue doesn't need to worry about.  However, unlike Blue, LockMart knows just how to sell it to the military.

Offline Hug

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Re: CIS Lunar Transporter, what do we know?
« Reply #55 on: 05/28/2023 05:46 am »
They certainly did say that Lockheed was leading and building/what not, but without specifics I just feel like it gives enough room for Blue to be involved. I mean technically, SLS is NASA's rocket despite most things being built by contractors. The thing with ULA is is that we didn't get much out of Blue before the announcement; but the one thing we did get was a list of contractors. And there isn't any mention of ULA on that list (as far as I'm aware). And I feel like if they were going to be used in any major capacity they would've had to be included.

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #56 on: 05/28/2023 11:33 am »
Water ice has a larger volume than liquid ice.
And? solid water is denser than the equivalent liquid hydrogen and liquid oxygen, so what's the problem?
Quote
So storing it as ice is not ideal.
stores easily. the only difficult part is if liquid water turns solid while it's being stored



Quote
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Put it in a cardboard tube painted solar white, and give it a gentle roll. Stays solid.

Quote
As well, your not gonna be cracking it as a solid. That makes it to difficult to handle.
How? sure, the lack of convection makes melting ice slower, but neither time or heat heat are a problem at a depot. Take the ice bag out of the white cardboard tube, and put it in a Mylar box with an opening facing the sun
« Last Edit: 05/31/2023 08:35 am by JCRM »

Offline Greg Hullender

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Re: CIS Lunar Transporter, what do we know?
« Reply #57 on: 05/28/2023 02:48 pm »
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Where do you get this? I figure the blackbody temperature at Earth's distance from the sun to be 279 K or about 42° F.

Obviously real materials will vary a lot, but I don't see how you can say 500 degrees.

Offline Steven Pietrobon

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Re: CIS Lunar Transporter, what do we know?
« Reply #58 on: 05/30/2023 08:05 am »
And? solid water is denser than liquid oxygen, so what's the problem?

Sorry. LOX has a density of 1.149 kg/L, which is greater than the density of water ice at 0.917 kg/L.

https://www.govinfo.gov/content/pkg/GOVPUB-C13-26d428ad4ca587866a90da5f71b4a727/pdf/GOVPUB-C13-26d428ad4ca587866a90da5f71b4a727.pdf
https://en.wikipedia.org/wiki/Ice
« Last Edit: 05/30/2023 08:08 am by Steven Pietrobon »
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #59 on: 05/30/2023 09:20 pm »
And? solid water is denser than liquid oxygen, so what's the problem?

Sorry. LOX has a density of 1.149 kg/L, which is greater than the density of water ice at 0.917 kg/L.

https://www.govinfo.gov/content/pkg/GOVPUB-C13-26d428ad4ca587866a90da5f71b4a727/pdf/GOVPUB-C13-26d428ad4ca587866a90da5f71b4a727.pdf
https://en.wikipedia.org/wiki/Ice

Nothing wrong with answering a non-sequitur based on bad data with good data, but it doesn't really change the fact that it was a non-sequitur in the first place.

We entertain bad ideas, ideas with bad supporting evidence, and off-topic ideas all the time here.  But it's better when only 2 out of 3 of those things are true.

Offline warp99

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Re: CIS Lunar Transporter, what do we know?
« Reply #60 on: 05/31/2023 05:45 am »
The HLS is said to have a dry mass of 16 tonnes and a wet mass of greater than or equal to 45 tonnes.  It will arrive in NRHO in the "dry" state but not completely or it would have no station keeping ability.  As you say it will launch on New Glenn. 


Do you have good numbers on the NG S2 size?  Mine are extremely stale and of questionable provenance.  The best ones I've found are from ZachF's post back in 2021.:

Isp = 445s (considerably more optimistic than yours)
O:F = 4.65:1
Dry Mass = 16.7t
Prop Mass = 175t

That would make ε = dry/(dry+prop) = 8.7%, which is a plausible number.  If these are right, this is a much bigger stage than I thought.

Quote
Instead the HLS can launch fully fueled to LEO and then get itself to NRHO since it has a higher Isp of the BE-7 of around 450s as a closed cycle expander and has a lower dry mass than NG S2.  I make it that it arrives with about 3.5 tonnes of propellant but in any case enough for an extended loiter in NRHO. 

Yes, there should be no problem sending the Blue Moon to NRHO from LEO under its own power, as long as it can be launched with enough hydrolox to make its wet mass 45t.

The big question is how big the BM tanks are.  Here are some possibilities:

Worst case: NRHO-LS(equatorial)-NRHO on its own:  prop = 46.4t, wet mass = 62.4t.
It does NRHO-LS(polar)-NRHO all on its own: prop = 41.8t, wet mass = 57.8t.
It has a reusable TE to take it to LLO: prop = 32.8t, wet mass = 48.8t.
It has a TE crasher to take it to sub-LLO: prop = 29.0t, wet mass = 45.0t.

All of these are consistent with Coulouris's "wet mass is north of 45t" statement.

I've attached my calculations for these four scenarios below, which include the Cislunar Transports required to service them.  Not exactly user-friendly, but you should get the gist.

Quote
The transfer vehicle then launches on New Glenn with say 12 tonnes dry mass and 33 tonnes of propellant.  It gets refueled by a tanker with 45 tonnes of propellant that can just be a slightly stretched NG S2 with refueling probe.  This then allows the transfer vehicle to get to NRHO and transfer 29 tonnes of propellant to the HLS.  This leaves the HLS short by about 1 km/s of the delta V to get to the Lunar surface and back.  The transfer stage stays docked to the HLS to do the initial parts of the landing burn and is then discarded and crashes into the Moon well past the landing site while the HLS completes the rest of the mission. 

The advantage is that only three New Glenn launches are required in total for the first mission and two launches for each subsequent mission.  The disadvantage is that the transfer vehicle is expended on each mission. 

I think this sounds like a fine plan, especially since the NG S2 is currently an expendable stage anyway.  Might as well crash it on the Moon as crash it in the ocean. 

However, it doesn't appear to be what they're doing.  Coulouris explicitly stated that the Cislunar Transport was a LockMart product/service, to be launched on a New Glenn. 

I suppose this doesn't rule out the possibility of it being some add-on kit to the NG S2, but it seems really unlikely.  If LockMart wants to build this, they're gonna want to use it for a variety of missions, and they're gonna want to launch it on a VC4 in addition to NG.  Given their position in the military payload biz, I'd expect them to want full control over this thing, with plans to use it for on-orbit servicing.  It would also allow them to bid on parts of DRACO, if that actually happens. That's likely a pretty good business model.

Quote
Looking at the case where the architecture is extended so that the transfer vehicle returns to LEO to be refueled the propellant requirement increases to 170 tonnes in LEO with a proportional increase in dry mass to around 20 tonnes.  Now it takes a total of five launches for the HLS and transfer vehicle plus three refueling flights for the first mission and three refueling flights for each subsequent mission.  As each flight requires a massive expendable S2 and fairing the cost structure actually favours expending the transfer vehicle.

You can do better than that if you're willing to aerobrake from TEI back into LEO.  If your vehicle can handle the heat pulse generated by a 20m/s aerobrake pass, getting from TEI to LEO takes less than 80days, which is more than adequate for their purposes.  From NRHO to some kind of reverse BLT (I think that should be a real thing), probably isn't more than 250m/s.  From LLO, I suspect it's better just to use regular TEI numbers (about 1030m/s, I think).

Update:  Fixed a problem in the reusable TE case.
I have done some more research on a few of the debatable points

1.  A bleed expander can be surprisingly efficient with the Japanese H2 upper stage engines reaching an Isp of 450s.  A value of 445s for the BE-3U is therefore quite feasible.  The BE-7 is more efficient as a closed cycle expander and could be 460s.

2.  It makes no sense to use the transfer stage for part of the Lunar landing burn as I originally proposed as it just adds to the dry mass.  Instead it needs to transfer more propellant to the lander so it can make its own way to the surface and back again.  I make it a delta V of 5500 m/s and 41 tonnes of propellant plus margin so 45 tonnes does look about right.

3.  At a 6:1 O:F ratio for the BE-7 45 tonnes of propellant gives 38.6 tonnes of LOX with a volume of 34 m3 and 6.4 tonnes of LH2 which has a volume of 91 m3.

4.  The lander LOX tank looks to be the key structural element that everything is tied to and I suspect it is a toroid for strength and to allow the LH2 downcomer to pass through with low thermal transfer. Assuming foam insulation about 100mm thick it is about 5.6m outer diameter and has a 2.2m diameter toroidal cross section.  That gives a LOX tank volume of 40 m3 which would allow another 10-15% propellant to be loaded if required.  Incidentally the crew cabin will also have a vacuum insulated pass through for the LOX and LH2 downcomers to the engines.

5.  An expendable transfer vehicle that ends up in NRHO and delivers 45 tonnes of propellant needs 3650 m/s of delta V from LEO so will have a dry mass of around 15 tonnes and 125 tonnes of propellant if using the BE-3U.  If it uses an RL-10 or BE-7 then that reduces to 120 tonnes of propellant so that hardly seems worth the extra cost and larger number of engines.  As you say if they can aerobrake gradually back to LEO that might allow reuse of the transfer stage.

6.  As I originally noted this can launch with 30 tonnes of propellant loaded and then top up with another 95 tonnes of propellant delivered in two New Glenn launches.  Note that I am proposing that a slightly stretched New Glenn S2 be used as a ground to LEO tanker - possibly with a fixed nose shell rather than a fairing.  The saving in fairing mass (6 tonnes?) could well allow an extra 3 tonnes of propellant per flight.  New Glenn S2 has far too high a dry mass to be used to get to NRHO - that is the job of the transfer stage. 

7.  The BE-3U reference you quoted had too low a thrust for each engine at 530kN and as a result the calculated propellant consumption was too low.  The Blue Origin web site consistently quotes 710 kN which pushes New Glenn stage 2 propellant consumption up to 325 kg/s.  For a GTO launch the payload is 13.6 tonnes and the stage dry mass work out as 26.4 tonnes with 232 tonnes of propellant loaded.  This gives a dry mass percentage of 10.2%.  That is actually pretty reasonable for a hydrolox stage although much worse that the 4% achieved by a kerolox stage like F9 S2.
« Last Edit: 05/31/2023 06:41 am by warp99 »

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #61 on: 05/31/2023 08:55 am »
And? solid water is denser than liquid oxygen, so what's the problem?

Sorry. LOX has a density of 1.149 kg/L, which is greater than the density of water ice at 0.917 kg/L.

You're forgetting ice III, with it's density of 1.160 kg/L   ;) :p

I've corrected the original, which was intended to point out it was still considerably denser than it's separated parts.

The marginal difference between the density of water in it's solid and liquid phases, combined with the area/volume is, I would suggest, compensated for by the ease of manipulation and the elimination of slosh

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #62 on: 05/31/2023 09:06 am »
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Where do you get this? I figure the blackbody temperature at Earth's distance from the sun to be 279 K or about 42° F.

Obviously real materials will vary a lot, but I don't see how you can say 500 degrees.

That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)


Offline warp99

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Re: CIS Lunar Transporter, what do we know?
« Reply #63 on: 05/31/2023 12:13 pm »
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Where do you get this? I figure the blackbody temperature at Earth's distance from the sun to be 279 K or about 42° F.

Obviously real materials will vary a lot, but I don't see how you can say 500 degrees.

That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)
Can I ask how you can have a surface with no back? 

Do you mean a heavily insulated rear surface?
« Last Edit: 05/31/2023 09:36 pm by warp99 »

Offline Greg Hullender

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Re: CIS Lunar Transporter, what do we know?
« Reply #64 on: 05/31/2023 05:00 pm »
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Where do you get this? I figure the blackbody temperature at Earth's distance from the sun to be 279 K or about 42° F.

Obviously real materials will vary a lot, but I don't see how you can say 500 degrees.

That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)

Sure, you can get much higher temperatures if you work at it. You can also get much lower temperatures if you work at it. So what's the justification for claiming that "sunlight is 500 degrees in space?"

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #65 on: 05/31/2023 11:45 pm »
I have done some more research on a few of the debatable points

1.  A bleed expander can be surprisingly efficient with the Japanese H2 upper stage engines reaching an Isp of 450s.  A value of 445s for the BE-3U is therefore quite feasible.  The BE-7 is more efficient as a closed cycle expander and could be 460s.

That's plausible, but it requires a lot of expansion.  Nozzle weight will be a problem.  At a guess, it seems like trading away a bit of Isp for better engine T/W would make sense, especially with multiple BE-7's per Blue Moon.

Quote
2.  It makes no sense to use the transfer stage for part of the Lunar landing burn as I originally proposed as it just adds to the dry mass.  Instead it needs to transfer more propellant to the lander so it can make its own way to the surface and back again.  I make it a delta V of 5500 m/s and 41 tonnes of propellant plus margin so 45 tonnes does look about right.

Per NASA's trade study, 5500m/s is a bit low.  They had a total of 5665m/s, but I think that includes 2% flight performance reserve.  See attached.

Quote
...
4.  The lander LOX tank looks to be the key structural element that everything is tied to and I suspect it is a toroid for strength and to allow the LH2 downcomer to pass through with low thermal transfer. Assuming foam insulation about 100mm thick it is about 5.6m outer diameter and has a 2.2m diameter toroidal cross section.  That gives a LOX tank volume of 40 m3 which would allow another 10-15% propellant to be loaded if required.  Incidentally the crew cabin will also have a vacuum insulated pass through for the LOX and LH2 downcomers to the engines.

A toroidal tank doesn't make sense, unless the downcomer is going to go through the middle of the crew module--which it won't.  I'd count on vanilla-flavored cylindrical tanks with ellipsoidal end caps, and downcomers going down the sides of the vehicle.  Whether Blue Moon has a full inter-tank or just an LH2-LOX bulkhead is a good question.  A hefty cryocooler covers a multitude of sins.

Quote
5.  An expendable transfer vehicle that ends up in NRHO and delivers 45 tonnes of propellant needs 3650 m/s of delta V from LEO so will have a dry mass of around 15 tonnes and 125 tonnes of propellant if using the BE-3U.  If it uses an RL-10 or BE-7 then that reduces to 120 tonnes of propellant so that hardly seems worth the extra cost and larger number of engines.  As you say if they can aerobrake gradually back to LEO that might allow reuse of the transfer stage.

3600m/s is too much.  BLT with lunar flyby (which takes longer) can be C3 = -1.5km²/s², which is about 3130m/s with no inclination changes.  Call it 3200m/s with inclination.  Then you have about 100m/s for NRHO insertion, and ~50m/s for RPOD.  Add in 2% for residuals and FPR:  3420m/s.

But if you're going to reuse the CT (and that's the plan), then you need an extra 200m/s for NRHO-to-BLT insertion, plus some mid-course fiddling.  This assumes aerobraking back into LEO, so you'll need a few tens of m/s for braking errors, plus 70m/s to raise the perigee after aerobraking is complete.  Call it... 400m/s with residuals and FPR?
« Last Edit: 06/01/2023 03:35 am by TheRadicalModerate »

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #66 on: 06/01/2023 10:42 am »


That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)
Can I ask how you can have a surface with no back? 

Do you mean a heavily insulated rear surface?
No, I mean an interior.

If you need that explained further,  a black body calculation is a massive simplification, which gives very good results. Black bodies are isothermal, so anything inside has to be treated an insulator, doesn't matter whether it's a good or bad insulator, because that only effects the time taken to reach a steady state, not the steady state reached. (that of course, is only strictly true with this second order, but still very simplified model, but it gives very good results)

The steady state achieved will be a thermal gradient across the interior with the hot side the temperature of the heat source facing single surface black body, and the cold side the temperature of the ambient facing single surface black body


Offline warp99

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Re: CIS Lunar Transporter, what do we know?
« Reply #67 on: 06/01/2023 11:25 am »


That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)
Can I ask how you can have a surface with no back? 

Do you mean a heavily insulated rear surface?
No, I mean an interior.

If you need that explained further,  a black body calculation is a massive simplification, which gives very good results. Black bodies are isothermal, so anything inside has to be treated an insulator, doesn't matter whether it's a good or bad insulator, because that only effects the time taken to reach a steady state, not the steady state reached. (that of course, is only strictly true with this second order, but still very simplified model, but it gives very good results)

The steady state achieved will be a thermal gradient across the interior with the hot side the temperature of the heat source facing single surface black body, and the cold side the temperature of the ambient facing single surface black body
I agree that a black body is isothermal which means that its entire surface is at the same temperature. 
However this implies that is a perfect thermal conductor with zero thermal resistance which of course can only be approximated as a real world object.  Many metals such as copper and aluminium are close enough to meeting that definition. 

You seem to be redefining isothermal to mean zero heat flux through the surface.

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #68 on: 06/01/2023 05:21 pm »
The proper criterion is that the body be in thermodynamic equilibrium. Then:

solarFlux*incidentArea*absorptance = radiatingArea*emissivity*boltzmannConstant*T^4

Solve for temperature T.

Update:  I forgot some terms.  Added them.
« Last Edit: 06/03/2023 05:04 am by TheRadicalModerate »

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #69 on: 06/01/2023 06:03 pm »
As well, sunlight is 500 degrees in space. So still gonna need serious cooling no matter what your doing.
Where do you get this? I figure the blackbody temperature at Earth's distance from the sun to be 279 K or about 42° F.

Obviously real materials will vary a lot, but I don't see how you can say 500 degrees.

That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)

Sure, you can get much higher temperatures if you work at it. You can also get much lower temperatures if you work at it. So what's the justification for claiming that "sunlight is 500 degrees in space?"
The point is you don't have to work to get much higher temperatures in space; they happen all by themselves.

You do have to work very hard indeed to get lower temperatures than black bodies though.

I'm assuming the 500 (not my claim) has a source, for example the surveyors exceeded 420 degrees Kelvin (I wouldn't use degrees with Kelvin, but it is legit)

Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #70 on: 06/01/2023 06:09 pm »



That's the temperature for a black body sphere

Far higher temperatures are achieved by a single surface facing the sun (no back surface)
Can I ask how you can have a surface with no back? 

Do you mean a heavily insulated rear surface?
No, I mean an interior.

If you need that explained further,  a black body calculation is a massive simplification, which gives very good results. Black bodies are isothermal, so anything inside has to be treated an insulator, doesn't matter whether it's a good or bad insulator, because that only effects the time taken to reach a steady state, not the steady state reached. (that of course, is only strictly true with this second order, but still very simplified model, but it gives very good results)

The steady state achieved will be a thermal gradient across the interior with the hot side the temperature of the heat source facing single surface black body, and the cold side the temperature of the ambient facing single surface black body
I agree that a black body is isothermal which means that its entire surface is at the same temperature. 
However this implies that is a perfect thermal conductor with zero thermal resistance which of course can only be approximated as a real world object.  Many metals such as copper and aluminium are close enough to meeting that definition. 


No, not just the surface, the entire body.

And yes, that's what it implies.

Yes, an object that is made solely of such metals are close enough.

but payloads aren't made of solid metal (well, some are, but they're outliers)

... or perhaps NASA were delusional when they put Apollo into a slow roll.

« Last Edit: 06/01/2023 06:21 pm by JCRM »

Offline Steven Pietrobon

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Re: CIS Lunar Transporter, what do we know?
« Reply #71 on: 06/03/2023 03:28 am »
... or perhaps NASA were delusional when they put Apollo into a slow roll.

The slow roll was to protect the heatshield from cracking due to a thermal difference between the hot and cold sides. Rolling evenly distributed the temperature.
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Offline JCRM

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Re: CIS Lunar Transporter, what do we know?
« Reply #72 on: 06/03/2023 09:57 am »
... or perhaps NASA were delusional when they put Apollo into a slow roll.

The slow roll was to protect the heatshield from cracking due to a thermal difference between the hot and cold sides. Rolling evenly distributed the temperature.
... because the surface wasn't isothermal

Re: CIS Lunar Transporter, what do we know?
« Reply #73 on: 06/03/2023 04:10 pm »
Here's a question: If you have a cryocooler on the Transporter anyway, will that minimize boil-off enough that a 6-12 month transfer to the Moon using Solar Electric Propulsion is possible, without losing too much hydrogen?

Because if you can swing that, it suddenly becomes plausible to launch the entire propellant load for Blue Moon in a single New Glenn launch. It would also further explain why Blue brought in Lockheed Martin for the Transporter, since LM has spent a lot more time studying not only cryogenics and depots, but also SEP.
Wait, ∆V? This site will accept the ∆ symbol? How many times have I written out the word "delta" for no reason?

Offline Tywin

Re: CIS Lunar Transporter, what do we know?
« Reply #74 on: 06/03/2023 07:06 pm »
Here's a question: If you have a cryocooler on the Transporter anyway, will that minimize boil-off enough that a 6-12 month transfer to the Moon using Solar Electric Propulsion is possible, without losing too much hydrogen?

Because if you can swing that, it suddenly becomes plausible to launch the entire propellant load for Blue Moon in a single New Glenn launch. It would also further explain why Blue brought in Lockheed Martin for the Transporter, since LM has spent a lot more time studying not only cryogenics and depots, but also SEP.

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Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #75 on: 06/03/2023 10:45 pm »
Here's a question: If you have a cryocooler on the Transporter anyway, will that minimize boil-off enough that a 6-12 month transfer to the Moon using Solar Electric Propulsion is possible, without losing too much hydrogen?

Because if you can swing that, it suddenly becomes plausible to launch the entire propellant load for Blue Moon in a single New Glenn launch. It would also further explain why Blue brought in Lockheed Martin for the Transporter, since LM has spent a lot more time studying not only cryogenics and depots, but also SEP.

I don't know what low-thrust delta-v is from LEO to NRHO, but the rule-of thumb is to subtract the departure orbit speed (about 7780m/s) from the destination orbit speed (the Moon orbits the Earth about about 1020m/s).  Then we'd have to add some fudge factor for actually inserting into NRHO--maybe 500m/s?  So we're looking at 7260m/s of delta-v each way.

Let's assume a 14t dry mass (hydrolox tankage, solar arrays, and noble gas propellant tankage).  Use Hall thruster Isp of... 2500s?  So, to get back from NRHO to LEO, with empty hydrolox tanks, we'll need 4.8t of propellant.

So inert mass for the outbound trip is 14t dry mass + 45t hydrolox + 4.8t return prop = 63.8t.  So 7260m/s of delta-v costs 22.0t of additional prop.

Total wet mass from LEO:  14t dry + 26.8t prop + 45t hydrolox = 85.8t, 71.8t of which have to be brought as consumables for the next mission.

That's 2 New Glenns, instead of 3 for a hydrolox propulsion system.  Better'n a sharp stick in the eye, but it's a lot of work.

Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.

Re: CIS Lunar Transporter, what do we know?
« Reply #76 on: 06/03/2023 11:21 pm »
Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.

Wait, what? Why would the military need the CIS Lunar Transporter? What are they gonna do, launch 45 ton GEO birds? What is that gonna do that LEO mega constellations can't?
Wait, ∆V? This site will accept the ∆ symbol? How many times have I written out the word "delta" for no reason?

Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #77 on: 06/03/2023 11:42 pm »
Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.

Wait, what? Why would the military need the CIS Lunar Transporter? What are they gonna do, launch 45 ton GEO birds? What is that gonna do that LEO mega constellations can't?
Well, whatever the heck DARPA wants to use nuclear thermal propulsion for, for one.
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Re: CIS Lunar Transporter, what do we know?
« Reply #78 on: 06/04/2023 12:00 am »
Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.
Wait, what? Why would the military need the CIS Lunar Transporter? What are they gonna do, launch 45 ton GEO birds? What is that gonna do that LEO mega constellations can't?
Well, whatever the heck DARPA wants to use nuclear thermal propulsion for, for one.
Fair enough.
Wait, ∆V? This site will accept the ∆ symbol? How many times have I written out the word "delta" for no reason?

Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #79 on: 06/04/2023 03:34 am »
Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.

Wait, what? Why would the military need the CIS Lunar Transporter? What are they gonna do, launch 45 ton GEO birds? What is that gonna do that LEO mega constellations can't?

Sit in GEO or MEO (or LEO, for that matter) with giant telescopes looking at fixed spots on the ground 24/7/365.  And then, when anti-satellite systems come after them, they're gonna run away, which takes propellant.  Which they're going to have to get from somewhere.

None of this should be news.  It's been widely reported that the military wants refueling capabilities as part of their strategy to make space assets more robust.  And there's nobody better positioned to provide those capabilities than LockMart.

Re: CIS Lunar Transporter, what do we know?
« Reply #80 on: 06/04/2023 03:19 pm »
Another thing to consider:  LockMart almost certainly wants to use this thing for military missions, which have much tighter time constraints on them than a once-a-year Artemis cadence.  SEP might not work for those.

Wait, what? Why would the military need the CIS Lunar Transporter? What are they gonna do, launch 45 ton GEO birds? What is that gonna do that LEO mega constellations can't?

Sit in GEO or MEO (or LEO, for that matter) with giant telescopes looking at fixed spots on the ground 24/7/365.  And then, when anti-satellite systems come after them, they're gonna run away, which takes propellant.  Which they're going to have to get from somewhere.

None of this should be news.  It's been widely reported that the military wants refueling capabilities as part of their strategy to make space assets more robust.  And there's nobody better positioned to provide those capabilities than LockMart.

Ok, sure. But I've never had any reason to suspect they meant anything besides hypergolic refueling. Why on Earth would they need cryogenic propellant to fulfil that mission?

Also, I might suggest that Northrop Grumman, having already demonstrated much of the necessary technology with the Mission Extension Vehicle, are better positioned to provide those capabilities than LM.
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Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #81 on: 06/04/2023 04:26 pm »
Why on Earth? Because of the much higher Isp it allows. The same reason DARPA apparently wants nuclear thermal propulsion.
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Re: CIS Lunar Transporter, what do we know?
« Reply #82 on: 06/04/2023 05:57 pm »
Why on Earth? Because of the much higher Isp it allows. The same reason DARPA apparently wants nuclear thermal propulsion.

Ok, then why do they think they need higher isp for the use case described. Which was (I think rather clearly) my actual question.
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Offline Robotbeat

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Re: CIS Lunar Transporter, what do we know?
« Reply #83 on: 06/04/2023 07:23 pm »
To have a maneuvering advantage over enemies using storables. Also, the technology for hydrolox cryogenic refueling is kind of a prerequisite to doing the same for nuclear thermal.

Hydrolox may only have a 50% greater Isp advantage over storables, but nuclear thermal has a 200% greater advantage (meaning for the same mass of propellant, you can maneuver thru 3 times the delta-v), and hydrolox refueling buys down a ton of risk for nuclear thermal.
« Last Edit: 06/04/2023 07:29 pm by Robotbeat »
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Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #84 on: 06/04/2023 08:13 pm »
Ok, sure. But I've never had any reason to suspect they meant anything besides hypergolic refueling. Why on Earth would they need cryogenic propellant to fulfil that mission?

Also, I might suggest that Northrop Grumman, having already demonstrated much of the necessary technology with the Mission Extension Vehicle, are better positioned to provide those capabilities than LM.

Fair point, although getting lots of hypergolics to where they need to go is still a legitimate use for hydrolox--especially if you already have the tech.

Another point:  LH2 is also a refrigerant consumable for a lot of optical sensor applications.

It'd be interesting to look at a full-up mass balance for big military payloads using hydrolox propulsion rather than storables.  The mass and volume of the tanks is obviously an issue, but it's a lot less of an issue with Category C fairings and heavier lifters.  Medium term, if you're running away from co-orbital ASATs, the strategy is to ensure that the predator runs out of medium-thrust delta-v before the prey.  If hydrolox helps with that, and the ZBO tech exists to enable its long-term storage, why wouldn't the DoD start using it?

I'm skeptical that anything will come of DRACO, but it's certainly oriented toward exactly this kind of "nyah, nyah, nyah, can't catch me!" strategy.
« Last Edit: 06/04/2023 08:45 pm by TheRadicalModerate »

Re: CIS Lunar Transporter, what do we know?
« Reply #85 on: 06/04/2023 09:08 pm »
I guess the only other thing I want to say on this is that it seems like you have sort of skipped to step 3 of this arms race. I agree with your logic here; some day in the future, military satellites will need more performance, and some day after that, they'll need the further performance boost hydrogen can provide. But they don't need it today, and I don't see any reason to believe they'll need it in the next 10 years, barring an actual world war great power conflict. So I don't see much reason for Lockheed Martin to be thinking about military missions while making decisions for the Cislunar Transporter, which is definitely a next-5-years project.

I don't think the Transporter has military relevance as anything other than a technology demonstrator/incubator.
« Last Edit: 06/05/2023 04:55 pm by JEF_300 »
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Offline TheRadicalModerate

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Re: CIS Lunar Transporter, what do we know?
« Reply #86 on: 06/05/2023 05:28 am »
I guess the only other thing I want to say on this is that it seems like you have sort of skipped to step 3 of this arms race. I agree with your logic here; some day in the future, military satellites will need more performance, and some day after that, they'll need the further performance boost hydrogen can provide. But they don't need it today, and I don't see any reason to believe they'll need it in the next 10 years, barring an actual world war great power conflict. So I don't see much reason for Lockheed Martin to be thinking about military missions while making decisions for the CIS Lunar Transporter, which is definitely a next-5-years project.

I don't think the Transporter has military relevance as anything other than a technology demonstrator/incubator.

I'd think that USSF and NRO would be designing the payloads for that arms race now, and they'd need to know that they were refuelable, with hydrolox or otherwise, in high-energy orbits, before they committed to the designs.

And I know that I'm being borderline obsessive and annoying, but I can't help myself:  "Cislunar," not "CIS Lunar".

Offline DrHeywoodFloyd

Re: CIS Lunar Transporter, what do we know?
« Reply #87 on: 06/05/2023 05:42 am »
I guess the only other thing I want to say on this is that it seems like you have sort of skipped to step 3 of this arms race. I agree with your logic here; some day in the future, military satellites will need more performance, and some day after that, they'll need the further performance boost hydrogen can provide. But they don't need it today, and I don't see any reason to believe they'll need it in the next 10 years, barring an actual world war great power conflict. So I don't see much reason for Lockheed Martin to be thinking about military missions while making decisions for the CIS Lunar Transporter, which is definitely a next-5-years project.

I don't think the Transporter has military relevance as anything other than a technology demonstrator/incubator.

I'd think that USSF and NRO would be designing the payloads for that arms race now, and they'd need to know that they were refuelable, with hydrolox or otherwise, in high-energy orbits, before they committed to the designs.

And I know that I'm being borderline obsessive and annoying, but I can't help myself:  "Cislunar," not "CIS Lunar".

I have the same problem... "CT" perhaps?

Offline meekGee

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Re: CIS Lunar Transporter, what do we know?
« Reply #88 on: 06/05/2023 10:15 am »
To have a maneuvering advantage over enemies using storables. Also, the technology for hydrolox cryogenic refueling is kind of a prerequisite to doing the same for nuclear thermal.

Hydrolox may only have a 50% greater Isp advantage over storables, but nuclear thermal has a 200% greater advantage (meaning for the same mass of propellant, you can maneuver thru 3 times the delta-v), and hydrolox refueling buys down a ton of risk for nuclear thermal.
To nit pick, and it's a large nit, and applies to all the high ISP technology discussions.

You get 3x the impulse, not 3x the dV.

The dV is equally influenced by dry mass, which for many high ISP technologies is high.

We all know that, but it's easy to forget.

For high-dV mission profiles, eventually the ISP wins, but I am not sure all this maneuvering requires high dV.

It might require high thrust/mass though.
ABCD - Always Be Counting Down

Re: CIS Lunar Transporter, what do we know?
« Reply #89 on: 06/05/2023 04:54 pm »
And I know that I'm being borderline obsessive and annoying, but I can't help myself:  "Cislunar," not "CIS Lunar".

I genuinely had no idea which was right. I was just going off the threat title.
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Offline DrHeywoodFloyd

Re: Cislunar Transporter, what do we know?
« Reply #90 on: 06/08/2023 12:42 pm »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage

Online TrevorMonty

Re: Cislunar Transporter, what do we know?
« Reply #91 on: 06/08/2023 05:06 pm »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage
From the article.

The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket. 

Online Asteroza

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Re: Cislunar Transporter, what do we know?
« Reply #92 on: 06/09/2023 12:02 am »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage
From the article.

The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket.

So tank module and service module perhaps? Makes sense from a function and mass split, but if you want a relatively dumb tank block, the service module will need a minimum amount of propellant storage for RPOD/tank chasing.

Offline GWH

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Re: Cislunar Transporter, what do we know?
« Reply #93 on: 06/09/2023 01:01 am »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage
From the article.

The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket.

So tank module and service module perhaps? Makes sense from a function and mass split, but if you want a relatively dumb tank block, the service module will need a minimum amount of propellant storage for RPOD/tank chasing.

The inside of the fairing is about 17 meters tall (I think the PUG has it at 18.5, the below graphic is a bit older). So roughly two full length modules to make up the 34 meters.

H2 tank and then O2 tank + service module would make up the split a bit better I'd think.

Way larger than I was expecting! I'm pretty excited that they're thinking at that scale.
« Last Edit: 06/09/2023 01:02 am by GWH »

Offline Hug

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Re: Cislunar Transporter, what do we know?
« Reply #94 on: 06/09/2023 01:33 am »
I mean I was certainly wrong and this is a huge stage. Like almost bigger than the New Glenn second stage which blows past my assumptions. At this size they doing propulsive burn to get back to LEO instead of aerobraking right?
« Last Edit: 06/09/2023 01:38 am by Hug »

Offline GWH

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Re: Cislunar Transporter, what do we know?
« Reply #95 on: 06/09/2023 01:53 am »
A Centaur V derived tank would make a lot of sense here.  5 meter diameter, fantastic mass fraction, tooling is available.

Then they can take up the extra 1.2m of space with a combination of insulation and a sun shield stood off the sides of the tank. All tucked away under the fairing for launch.
« Last Edit: 06/09/2023 01:54 am by GWH »

Offline TheRadicalModerate

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Re: Cislunar Transporter, what do we know?
« Reply #96 on: 06/09/2023 06:43 pm »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage
From the article.

The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket.

So tank module and service module perhaps? Makes sense from a function and mass split, but if you want a relatively dumb tank block, the service module will need a minimum amount of propellant storage for RPOD/tank chasing.

This is close to what I was thinking of here, but instead of just a bus and a variety of different tanks, it sounds like they could be launching a full Centaur V kitted up with ACES extensions, sunshades, and radiators, and then a big hydrolox tank.

Centaur V holds 54t of prop in a tank that's ~8m long by 5.4m wide.  (8m is an arm-wave because I don't know the dimensions of the end caps and the width of the inter-tank bulkhead.  RL10CX is supposed to be O:F=5.5:1, which would make boiling average density of the hydrolox about 350kg/m³, which would require 154m³ of volume.  At a 5.4m diameter, that's 6.7m of cylindrical length.)

A second 5.4m-wide tank, assuming that it's docked to the Centaur by the New Glenn second stage (i.e., it doesn't have its own bus, with RCS thrusters), could be as long as ~14m, which would allow it to contain 101.7t of prop.  (I applied the same volume fudge-factor, about 30m³, to this as I did to the Centaur computation.)

That's more than enough prop to refuel the Blue Moon and have both the Centaur and the dumb tank return to LEO via a propulsive insert.  It's also has a low enough structural coefficient that they can probably manage to fill a Blue Moon for a polar landing with 3 New Glenn propellant launches.  (An equatorial mission will take 4.)

This is obviously all predicated on the idea that they're starting from Centaur V, which in turn pretty much requires that LockMart buy Boeing out of ULA.  But the idea of using standard Centaur V tank manufacturing, coupled with all the ACES mods they left on the shelf, yields a project with low development risk that's highly flexible for other missions.  If you want to ship LH2 to a nuke, you can replace the dumb hydrolox tank with a dumb LH2 tank.  You could even stack multiple dumb tanks.

The other thing that a dumb tank provides is the infrastructure to execute Tory's "Strategic Propellant Reserve" vision:  The CT can move the dumb tanks to where they're needed, dock them to some kind of stripped-down ACES infrastructure, and return back to LEO for more.

Kinda slick.

Offline DrHeywoodFloyd

Re: Cislunar Transporter, what do we know?
« Reply #97 on: 06/09/2023 11:52 pm »
This is interesting, and the author talks with Kirk Shireman of Lockheed about the difficulties of cryogenic refueling, and what they are doing to resolve it...

https://qz.com/emails/space-business/1850514330/space-business-cold-storage
From the article.

The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket.

So tank module and service module perhaps? Makes sense from a function and mass split, but if you want a relatively dumb tank block, the service module will need a minimum amount of propellant storage for RPOD/tank chasing.

This is close to what I was thinking of here, but instead of just a bus and a variety of different tanks, it sounds like they could be launching a full Centaur V kitted up with ACES extensions, sunshades, and radiators, and then a big hydrolox tank.

Centaur V holds 54t of prop in a tank that's ~8m long by 5.4m wide.  (8m is an arm-wave because I don't know the dimensions of the end caps and the width of the inter-tank bulkhead.  RL10CX is supposed to be O:F=5.5:1, which would make boiling average density of the hydrolox about 350kg/m³, which would require 154m³ of volume.  At a 5.4m diameter, that's 6.7m of cylindrical length.)

A second 5.4m-wide tank, assuming that it's docked to the Centaur by the New Glenn second stage (i.e., it doesn't have its own bus, with RCS thrusters), could be as long as ~14m, which would allow it to contain 101.7t of prop.  (I applied the same volume fudge-factor, about 30m³, to this as I did to the Centaur computation.)

That's more than enough prop to refuel the Blue Moon and have both the Centaur and the dumb tank return to LEO via a propulsive insert.  It's also has a low enough structural coefficient that they can probably manage to fill a Blue Moon for a polar landing with 3 New Glenn propellant launches.  (An equatorial mission will take 4.)

This is obviously all predicated on the idea that they're starting from Centaur V, which in turn pretty much requires that LockMart buy Boeing out of ULA.  But the idea of using standard Centaur V tank manufacturing, coupled with all the ACES mods they left on the shelf, yields a project with low development risk that's highly flexible for other missions.  If you want to ship LH2 to a nuke, you can replace the dumb hydrolox tank with a dumb LH2 tank.  You could even stack multiple dumb tanks.

The other thing that a dumb tank provides is the infrastructure to execute Tory's "Strategic Propellant Reserve" vision:  The CT can move the dumb tanks to where they're needed, dock them to some kind of stripped-down ACES infrastructure, and return back to LEO for more.

Kinda slick.

Thank you, excellent analysis!
My hypothesis: A key part of this of this strategy [not mentioned, but makes sense..] would be the establishment of fuel depots at LEO and Lunar Orbit, why: Decoupling!

Value added: Decoupling
One of the biggest benefits of a propellant depot, particularly one with fairly decent sized tanks is the  complete decoupling between endcomplete decoupling between end--user's vehicle and suppliers' vehiclesuser's vehicle and suppliers' vehicles. For instance, with a buffer tank like that, you could reasonablyuse high flight-rate, small RLVs (in the 1000-3000lb payload class) to refuel the depot, while the depot refuels a large transfer stage (e.g. 100,000lb propellant class). The large transfer stage only has to deal with a single docking event, so the odds of damage to it are much smaller than if it had to handle 30-100 docking events. "
>> Propellant Depots for In-orbit Lunar infrastructures, ESA: https://sci.esa.int/c/portal/doc.cfm?fobjectid=42075




>> LEO Propellant Depot: Servicing Impact on Space Missions, NASA (.gov), NASA GSFC International Servicing Workshop. March 24-26, 2010, https://nexis.gsfc.nasa.gov/workshop_2010/day1/Dallas_Bienhoff/100324_LPD_GSFC_Servicing.pdf

>> "Commentary | Propellant Depots Instead of Heavy Lift?":  https://spacenews.com/propellant-depots-instead-heavy-lift/

>> NASA Is Considering Fuel Depots in the Skies: https://www.nytimes.com/2011/10/23/science/space/23nasa.html


Offline TheRadicalModerate

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Re: Cislunar Transporter, what do we know?
« Reply #98 on: 06/10/2023 03:49 am »
My hypothesis: A key part of this of this strategy [not mentioned, but makes sense..] would be the establishment of fuel depots at LEO and Lunar Orbit, why: Decoupling!

As a general rule, prop depots in higher-energy orbits (and NRHO or LLO qualify) are a bad idea.  The trick is always to fill your vehicle in the lowest-possible energy orbit that lets it complete its mission without refueling at higher energy.  This always results in the lowest amount of prop launched to LEO.

That said, if you're going to have an HLS that returns from its surface mission essentially empty, then you've already set the lowest-energy orbit to be NRHO, and you haul what you have to haul.

I have no idea what the logistical tail for cislunar space will look like as traffic picks up, and a cislunar depot might indeed be a nice biz case for somebody.  But I wouldn't do that first thing.

One step at a time.
« Last Edit: 06/10/2023 03:49 am by TheRadicalModerate »

Offline clongton

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Re: Cislunar Transporter, what do we know?
« Reply #99 on: 06/11/2023 11:43 am »
I've been told that there are some here at NSF that have ideas on how to do the Cis Lunar transport better than the current Artemis approach. Presenting those thoughts here would take this thread off-topic so I've started a new thread to allow exactly that discussion. It is located here: Alternative Cis Lunar Architectures

If you have thoughts on how you think cis-lunar transport should be done in lieu of how NASA is approaching it, you now have a space to flesh out those ideas and get some feedback. I've a few thoughts of my own so I'll also be presenting them for discussion and feedback. I'm looking forward to the discussions.
« Last Edit: 06/11/2023 11:43 am by clongton »
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Offline yg1968

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Re: Cislunar Transporter, what do we know?
« Reply #100 on: 06/11/2023 12:46 pm »
Space Business: Cold Storage
Elon Musk and Jeff Bezos are betting on unproven tech for NASA's return to the Moon
https://qz.com/emails/space-business/1850514330/space-business-cold-storage

Quote from: the article
The Cislunar Propellant Transporter will be a huge vehicle, some 34 meters long and launched in two parts by Blue Origin’s as-yet-to-fly New Glenn rocket. The idea is that once Blue’s lander reaches orbit around the Moon, it will remain there to shuttle astronauts down to the surface and back again. Afterward, it can be refueled and perform its next mission.

https://twitter.com/JeffVader10/status/1667113565193486336

« Last Edit: 06/11/2023 12:53 pm by yg1968 »

Offline GWH

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Re: Cislunar Transporter, what do we know?
« Reply #101 on: 06/11/2023 04:31 pm »
Over on reddit someone mentioned Lockheed's Jupiter space tug proposal for CRS2. As opposed to something Centaur V derived.

So I'm sitting here pondering the conops of Jupiter and this large two part tug and thinking... "why not both".

If this vehicle were built as a propulsion tug element with a robotic arm, just like Jupiter, then a Centaur V derived propulsion element could dock itself to a separate Centaur V derived storage tank.
Transport that out to NHRO, refuel the lander, and then either discard the tank or leave it in a parkimg orbit. Would save the round trip delta V penalty of that empty tank when taking the lander to LLO and then returning itself to NHRO.

https://en.m.wikipedia.org/wiki/Jupiter_(spacecraft)

« Last Edit: 06/11/2023 04:35 pm by GWH »

Offline DrHeywoodFloyd

Re: Cislunar Transporter, what do we know?
« Reply #102 on: 06/11/2023 09:46 pm »
Over on reddit someone mentioned Lockheed's Jupiter space tug proposal for CRS2. As opposed to something Centaur V derived.

So I'm sitting here pondering the conops of Jupiter and this large two part tug and thinking... "why not both".

If this vehicle were built as a propulsion tug element with a robotic arm, just like Jupiter, then a Centaur V derived propulsion element could dock itself to a separate Centaur V derived storage tank.
Transport that out to NHRO, refuel the lander, and then either discard the tank or leave it in a parkimg orbit. Would save the round trip delta V penalty of that empty tank when taking the lander to LLO and then returning itself to NHRO.

https://en.m.wikipedia.org/wiki/Jupiter_(spacecraft)



Thank you... for some reason, in my chrome browser clicking on the link, it interprets it as "https://en.m.wikipedia.org/wiki/Jupiter_(spacecraft"...anyway manually fixed the link and it works....

Anyway, there is also this video:



I would posit this is our CT... with minor updates

PS: One "out there" hypothesis watching this "space tug" operate with the international space station... is one day we actually might see it operate with Orbital Reef.... Just a thought... but I do believe that. it will be the LEO depot and termination point for CT... we will see how this evolves...

Anyway here is more information about it...
https://www.space.com/28815-jupiter-exoliner-lockheed-martin-spacecraft-photos.html

https://www.space.com/28817-jupiter-system-space-station-cargo-exploration.html
« Last Edit: 06/11/2023 09:56 pm by DrHeywoodFloyd »

Offline TheRadicalModerate

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Re: Cislunar Transporter, what do we know?
« Reply #103 on: 06/12/2023 04:41 am »
Over on reddit someone mentioned Lockheed's Jupiter space tug proposal for CRS2. As opposed to something Centaur V derived.

So I'm sitting here pondering the conops of Jupiter and this large two part tug and thinking... "why not both".

If this vehicle were built as a propulsion tug element with a robotic arm, just like Jupiter, then a Centaur V derived propulsion element could dock itself to a separate Centaur V derived storage tank.
Transport that out to NHRO, refuel the lander, and then either discard the tank or leave it in a parking orbit. Would save the round trip delta V penalty of that empty tank when taking the lander to LLO and then returning itself to NHRO.

Seems hard to adapt Jupiter to handling cryogens and to have 6000+m/s of delta-v to move around.

But I think you're barking up the right tree with the second tank.  This enables a whole bunch of things:

1) If you want to make a big depot, making it out of fairly dumb tanks is easier/cheaper than making it out of CTs.

2) If you have missions that really stretch the ability of the CT to get back to LEO, discarding the tank before return helps quite a bit.  (It also makes it easier for the CT to aerobrake, if that's what's required.)

3) There's nothing that says the second tank has to be hydrolox.  You can have a methalox variant.  You can have an MMH/NTO variant.  And you can have a pressurized variant, which would be a fine Gateway services competitor to DXL.

4) And, instead of a dumb cargo/prop tank, you can push a variety of human spacecraft here and there, eyeballs-out.

But I think the arm is counterproductive.  Just a slightly enhanced IDSS docking implementation will do fine, although it'll be necessary to flow hydrolox through the dumb tank into the CT tank--or dock a refueling tanker to the CT before it takes on some non-hydrolox payload.

It sure would be handy to use CT to send a tonne or two of storable prop to to GEO for satellite servicing.  But it costs about 8580m/s to go to GEO and back propulsively.    That requires about 70t of transit hydrolox.  If it's based on a Centaur V, that's a tank stretch that still fits in a New Glenn for launch, and can handle a 1-2t payload--plenty for satellite servicing.

This is probably dumb, because spending two New Glenn launches for a GEO service mission is kind of extravagant.  But the small payloads, and jobs those small payloads can do, are extremely flexible.  Given the choice between a well-understood bus that can do all the nitty-gritty maneuvering and a whole bunch of purpose-built gizmos that have to manage under their own power, maybe the extra NG launch starts looking pretty good.
« Last Edit: 06/12/2023 05:06 am by TheRadicalModerate »

Offline DrHeywoodFloyd

Re: Cislunar Transporter, what do we know?
« Reply #104 on: 06/15/2023 11:34 pm »
I am guessing that this press release from NASA might relate to a my hypothesis that orbital Reef would be a LEO depot for transportation of people and cargo out to the Moon...lets see how this evolves in the next ten years....

https://www.nasa.gov/press-release/seven-us-companies-collaborate-with-nasa-to-advance-space-capabilities

Online Asteroza

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Re: Cislunar Transporter, what do we know?
« Reply #105 on: 07/14/2023 06:54 am »

Offline yg1968

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Re: Cislunar Transporter, what do we know?
« Reply #106 on: 07/15/2023 02:36 pm »
« Last Edit: 07/15/2023 04:19 pm by yg1968 »

Online Asteroza

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Re: Cislunar Transporter, what do we know?
« Reply #107 on: 07/16/2023 10:27 pm »
Well, some oddities there.

Shared thin octagon bus for tug and tanker, asymmetric sunshields, surface differences between the three tanks (far white tank on the tug seems to be for LH2 but the size is wrong?)(tug blue tank appears to have something on it's surface)(long tank seems off?)

Offline Robert_the_Doll

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Re: Cislunar Transporter, what do we know?
« Reply #108 on: 07/17/2023 11:30 am »
Here is a higher resolution image of the cover. I would like to know if this is an official Blue Origin, Lockheed-Martin, etc. image as there are a lot of issues. The lander has only two BE-7s, centrally located, while we know it has three.


Offline ThatOldJanxSpirit

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Re: Cislunar Transporter, what do we know?
« Reply #109 on: 07/17/2023 02:52 pm »
Here is a higher resolution image of the cover. I would like to know if this is an official Blue Origin, Lockheed-Martin, etc. image as there are a lot of issues. The lander has only two BE-7s, centrally located, while we know it has three.

It’s marked as a ‘Blue Origin concept image’ in the magazine.

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Re: Cislunar Transporter, what do we know?
« Reply #110 on: 07/18/2023 01:11 am »
Huh, so tanker and tug both appear to have the same solar panel and radiator sizes, beyond sharing the same bus body?

Offline Zed_Noir

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Re: Cislunar Transporter, what do we know?
« Reply #111 on: 07/18/2023 05:39 am »
Well, some oddities there.

Shared thin octagon bus for tug and tanker, asymmetric sunshields, surface differences between the three tanks (far white tank on the tug seems to be for LH2 but the size is wrong?)(tug blue tank appears to have something on it's surface)(long tank seems off?)
Wonder if the tug element holds all the oxygen for the stack plus an auxiliary Hydrogen tank. While the tanker element only holds Hydrogen. The tankage on both elements are constrained by the "limited" volume of the New Glenn payload fairing. So you send up tanker element with a large liquid Hydrogen tank up to orbit first to wait for the tug element that has limited Delta-V by itself with the auxiliary Hydrogen tank (white tank?). AIUI the volume of the oxygen on the Cislunar Transport stack is limited by how much Hydrogen in volume you can crammed into the stack.

Offline ThatOldJanxSpirit

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Re: Cislunar Transporter, what do we know?
« Reply #112 on: 07/18/2023 06:51 am »
Huh, so tanker and tug both appear to have the same solar panel and radiator sizes, beyond sharing the same bus body?

The article notes common systems with the lander including the engines. LockMart is noted as providing ‘legacy hardware’ from Orion and its satellite division.

The transporter will include a solar powered ZBO system and can be used as a depot.

It looks to me that Blue is taking the development risk here.

Offline yg1968

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Re: Cislunar Transporter, what do we know?
« Reply #113 on: 07/20/2023 08:09 pm »
This presentation has a bit more on the LM Transporter (see attached image):

https://ntrs.nasa.gov/citations/20230010065

Quote
Human Landing System
Document ID  20230010065
Document Type  Presentation
Authors  Lisa Watson-Morgan
(Marshall Space Flight Center Redstone Arsenal, Alabama, United States)
Date Acquired  July 10, 2023

Online TrevorMonty

Re: Cislunar Transporter, what do we know?
« Reply #114 on: 07/21/2023 03:15 am »
Huh, so tanker and tug both appear to have the same solar panel and radiator sizes, beyond sharing the same bus body?

The article notes common systems with the lander including the engines. LockMart is noted as providing ‘legacy hardware’ from Orion and its satellite division.

The transporter will include a solar powered ZBO system and can be used as a depot.

It looks to me that Blue is taking the development risk here.
Finally somebody is going to create ZBO fuel depot and tank. This is huge step forward in space travel if it happens.

Its not just Blue that benefit from it but also ULA Vulcan. A fully fuelled Centuar V in LEO can deliver some serious payloads to lunar orbit but also elsewhere in solar system. By my estimates 12km/s for 5mt probe.
Also capable of delivering Orion to LLO if need be.

Depot also creates a market for ISRU fuel whether from moon or asteriods.
« Last Edit: 07/21/2023 03:21 am by TrevorMonty »

Offline warp99

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Re: Cislunar Transporter, what do we know?
« Reply #115 on: 07/29/2023 08:36 am »
Huh, so tanker and tug both appear to have the same solar panel and radiator sizes, beyond sharing the same bus body?
My take is that all three sets of propellant tanks are the same size and design differing only in the attachment struts and the type of insulation panels applied.  The difference is that the lander has petal like conformal radiators and solar panels to cope with sun angles at the Lunar south pole while the Transporter and Tanker have mast based panels as they can always adopt a nose to the sun orientation to suit their sun shields.  It is possible that the Lander nose cone can rotate so that the solar panels can stay oriented to the sun which is down on the horizon while the radiators remain in the shade.

The ZBO equipment will be the same for all three systems but packaged around the base of the LOX tank for the Transporter and Tanker while it is packaged on top of the Lander where the radiator and solar panels attach.  My take is that the LOX tank is toroidal for extra structural strength and to allow low heat transfer pass through of the LH2 pipes to the engines and refuelling ports.  However it may be that a double skinned downcomer is used instead for a passthough of an oval tank.

Offline yg1968

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Re: Cislunar Transporter, what do we know?
« Reply #116 on: 10/31/2023 10:53 pm »
https://twitter.com/wapodavenport/status/1719392648258068983

Attached are a few images of the cislunar transporter from these graphics:
« Last Edit: 11/01/2023 02:18 am by yg1968 »

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