Lockheed Martin's "Jupiter" reusable space tug, CRS-2 bid

[cdleonard]

Back to topic.  Jupiter would be a better deal if it took satellites to GSO from LEO or took them to L1 or L2 then returned.  Moving around in LEO doesn't mean much, unless it picks up old satellites and space debris and shoots is back into the atmosphere over an ocean for destruction.

Would it really be a good deal? Satellites already have propulsion systems for station-keeping. All that they need in order to do their orbit insertion is extra fuel and maybe even a special stronger engine.

Let's say you used a tug. Instead of paying for launching extra fuel in a bigger tank on your satellite you now have to pay in order to launch extra fuel for the the tug. You need more fuel because the tug needs to also take itself to GSO and back. Strictly from a mass-to-orbit perspective you would probably end up worse, right? And that's the biggest cost factor.

Where a tug would make sense is slowly transferring a very large and mostly dumb payload over a large delta-V. Something like a space station module or cargo pod. Sadly there's not much of a market for that.

Or maybe the NRO could pay for a tug instead of the Delta 4 Heavy for a GSO direct-inject mission. But those are really rare.

[savuporo]

The reason Jupiter is exciting is that it would be the first case of a vehicle that moves around in space and doesn't have to come back to Earth's surface to get refuelled.  That's pretty big. 

Uh .. this has been done since Salyut 6 IIRC.

Yeah, https://en.wikipedia.org/wiki/Salyut_6_EO-1#Progress_1
Progress: Refuelling things in Space (TM) Since January 29, 1978.

That's why I said "moving around".  There's a difference between a station being refuelled for maintaining its orbit and a vehicle that does substantial movement between orbits, and is, in fact, designed precisely for moving things from one orbit to another.

Is there actually a useful distinction here ? Progress and TKS and its descendants have moved things from low orbits to higher orbits, i.e. 'moving around' in space, good example being Salyut-7. Progress is precisely designed as a resupply vehicle as well.
I really wonder if Chinese sourced the propellant transfer and management from Russia for Shenzhou or no, because this is one unique capability that Russia has possessed with literally multiple decades of operations and experience, at large scale.

[Space Ghost 1962]

The point is that the problem is not technology, not operations.

Its just the dollars flowing to cheap payloads that might go out of country.

On the fear of losing "deal size" and ownership, we don't advance efficiency. Ever.

A battle of business models, masquerading as lessened risk.

Which makes perfect sense, if you believe in no increase in launch frequency. Zero sum game.

There's no need to get better because we are already perfect.

Jupiter's just one of many, and I'm not an advocate. Just annoys to see something near the threshold of change, and have things such as this narrow line of reasoning as the petty (but true) put down.

A better put down of Jupiter is the risk of an expensive tug needing to be frequently replaced. Or the off nominal "rescue" situations. However, a S/C vendor can deal with these in contract - that is why they are not raised.

[a_langwich]

One flaw in this argument is that Cygnus is riding on top of an execrable (for this application) solid rocket motor.  If Orbital were using a fantastically capable, space-restartable, high ISP upper stage which could refuel the tug and de-orbit the expended portions, they might easily offer NASA the ability to work on a Tug/Cargo upgrade.  But with the solid, they would only have a one-use tug/cargo system which has little benefit.

Not really. You could start the path of upgrade by creating an returnable cargo module with an detachable disposable stage. The inflatable heat-shield could offer some method or Orbital could partner with someone else to develop something that would increase station down mass but be low cost and quick to develop. Once you get re-usability then work on the tug part to make it reusable.

Jupiter doesn't do down mass.  That might be a nice feature, and in fact if Orbital does eventually do that test of NASA's HIAD on reentry, it may look into it as an out-past-CRS-2 future option for other Cygnus variants.

If you were thinking you could just inflate a HIAD or some other drag device to deorbit your cargo module, I don't think that's going to give you the accuracy to meet reentry safety criteria, it probably won't be very timely, and it limits the usefulness of your tug architecture to ISS or below.  And there's still the question, which I think Orbital will ultimately have to address anyway, of whether its solid upper stages are contributing to the space junk problem. 

Simply hauling an tank of propellant and using the smaller cheaper rocket could make up the difference. Now you won't get as much upmass as Jupiter, but Jupiter isn't the only starting point for an tug and this path could be easier for an company to develop and could run aside with Cygnus keeping the Original disposable form.

You can't just add a tank of propellant.  You have to add another stage, a transfer stage, that will have to fly on each flight, manuever in space with propulsion and inertial guidance, and then do the reentry burn.  In essence, a second tug to be expended, to enable the first tug to remain in orbit and be reusable.

If your tug has to do all the manuevering to reach a dumb tank, that means the propellant it needs per mission goes up.  Rendezvous with a dead, possibly tumbling object is much harder than with one under attitude and position control.

Once you've wiped out the upmass, the cost savings, the flexibility for so many different situations, have you really made an alternative?  Or have you built a steam-powered aeroplane which cannot get off the ground but which steampunk nerds think is cool?

Exchanging cargo modules is only one way to get an tug and it limits you to rockets with restart-able upper stages capable of lingering in Orbit and only ULA at the moment has or is very close to one of those. If there were two rockets that could lift and de-orbit then Jupiter could have some immediate benefit(i.e. allow the commercial cargo company to switch flights). But as it stands now there isn't and you would be limited to Atlas(or the un-competitive Delta) until raptor comes online.

Sure, there are other ways to modularize a cargo architecture.  A tiny few of them may actually make sense and be competitive.  The Jupiter architecture makes sense now.

Why do you think Jupiter has to be able to use multiple different LVs to have benefit?  Even if that were true, it could probably be tweaked to work on Delta IV as well.  But Dragon and AstroLiner can manage to be useful, even on just one LV.  And if SpaceX or Boeing or Orbital had a reason to want this, the Jupiter tug could always rendezvous with one of their cargo vessels and perhaps attach it to on-going work.  Or berth them to a commercial station.

In fact, Atlas is a wonderful launch vehicle.  Beyond its stellar success record, it is among the most flexible launch vehicles in terms of payload and performance to any particular C3, in a reasonable price range.  Delta IV has the Heavy, but the crowning benefit of Atlas has been its ability to reach 95% of the total commercial/military/science launch markets with just one core and add-on solids.  If Vulcan hits its price point, and its add-on solids hit their price points, it could be more than competitive with Falcon Heavy for some payload ranges.

In the context of Jupiter, this means its launch vehicle and the Centaur upper stage support a large variation in payload mass.  Or, support a large variation in the types of orbit it can reach.  Who said a Jupiter tug couldn't make it to GEO?  And its popularity means there might be all sorts of payloads launched on an Atlas with a Centaur upper stage which might then be one step away from using Jupiter to expand their mission capability, or restore their mission capability.

A Jupiter-class tug on top of ULA's distributed launch architecture could easily approach von Braun's vision of assembling a Mars-bound spaceship in earth orbit, but cheaply.  It points the way toward far more practical commercial station maintenance that doesn't require 24/7 staffing by humans.

"Oh there's nothing that the Wompom cannot !"   

[manboy]

But we must not lower the cost of spaceflight! Or increase its frequency! Or improve its reliability... And don't fly those complex missions like Philae, won't work ...

Those science missions do those complex tasks because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans. I'm skeptical Jupiter could compete with those vehicles on a cost basis. Also those pressurized vessels that get thrown away are not cheap.

If increased complexity isn't resulting in cost savings or increased capability then why defend it?

There's no need to get better because we are already perfect.

Who is making that claim?

The reason Jupiter is exciting is that it would be the first case of a vehicle that moves around in space and doesn't have to come back to Earth's surface to get refuelled.  That's pretty big.  Once space vehicles don't have to come back to Earth's surface for fuel, whole new levels of economics become possible.

Like I said, it may not work out to be worth it for the very narrow case of ISS resupply, but if we have larger aspirations, such a capability has very clear, huge advantages.

Then it sounds like you're not defending Jupiter but instead defending what you think it represents. Look I believe in-orbit refueling is probably the best path towards colonization but I just think the Jupiter proposal as a whole isn't a very good one.

[Space Ghost 1962]

Those science missions do those complex tasks because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans. I'm skeptical Jupiter could compete with those vehicles on a cost basis.

They represent developed, proven hardware that DOES DO THOSE THINGS. And they already function reliably over longer duration than the ENTIRE LIFE OF 10's to 100's of "deliveries".

Since one of them is needed to perform the function of 10 or 100 or more, perhaps the cost basis isn't the same as a one-shot?

Also those pressurized vessels that get thrown away are not cheap.

No they are not. By the way, the initial containerized, intermodal containers were also 10x more expensive (as well as having tracking/routing "features" that only now have a point) - once it was discovered that container reuse was much less infrequent, and that "intermodal" had a longer, riskier, harder time to be "absorbed" into the stodgy transportation industry, they got massively cheaper. Things adapt as you use them.

If increased complexity isn't resulting in cost savings or increased capability then why defend it?

Depends on the time it takes to recover the cost and/or prove the capability. Break even is typically what you look at, and that was around 10 or so. There are other benefits on top as well that are less "apples to apples".

There's no need to get better because we are already perfect.

Who is making that claim?

Implicit in the form used to eliminate the benefit as risk. I.e. that fewer dependent operations make for less mission risk, thus by induction the fewest operations (i.e. what we have now) is optimum, so you can't improve upon that. QED.

I run into this all the time. It's tiresome.

Business model changes in how we handle space are now essential to the business is my top level point here. This example with Jupiter is otherwise unremarkable.

[pathfinder_01]

You can't just add a tank of propellant.  You have to add another stage, a transfer stage, that will have to fly on each flight, manuever in space with propulsion and inertial guidance, and then do the reentry burn.  In essence, a second tug to be expended, to enable the first tug to remain in orbit and be reusable.

If your tug has to do all the manuevering to reach a dumb tank, that means the propellant it needs per mission goes up.  Rendezvous with a dead, possibly tumbling object is much harder than with one under attitude and position control.

I was thinking of an somewhat less passive cargo container. One that has some propulsion and station keeping capability.

Sure, there are other ways to modularize a cargo architecture.  A tiny few of them may actually make sense and be competitive.  The Jupiter architecture makes sense now.

Questionable that it makes sense now. Risky but there are not enough other carriers to mitigate it. It's one thing when you have enough cargo coming from other companies, but right now there are only two and I doubt NASA would select more than 2-3 companies for this contract. And the reason why we use modularity in transport on earth is because it give an clear benefit for operations involving that cargo(loading/unloading, switching between vehicles, switching between modes of transport). 

Here Jupiter is attempting reuse via modularity, but the dumb cargo container is attached to an modified expensive upper stage(Centaur), launched by an expensive rocket(Atlas or Delta). It is competing with vehicles already developed and in service(Cygnus, Dragon) and vehicles that could add a little extra cargo without as much development cost or fixed upkeep costs(CST-100).

Why do you think Jupiter has to be able to use multiple different LVs to have benefit?  Even if that were true, it could probably be tweaked to work on Delta IV as well.  But Dragon and AstroLiner can manage to be useful, even on just one LV.  And if SpaceX or Boeing or Orbital had a reason to want this, the Jupiter tug could always rendezvous with one of their cargo vessels and perhaps attach it to on-going work.  Or berth them to a commercial station.

They don't need Jupiter to berth them. To berth all you need is an robot arm. The berthing process could be automated but if humans are on board they should control it or monitor it. There is also the possibility of automatic docking.  The reason why you want the ability to switch rockets is because you may need it. This is an advantage of Cygnus which would be Jupiter's prime competitor. CST-100 is also able to switch. Dragon isn't but it has down mass as an selling point.

Who said a Jupiter tug couldn't make it to GEO?  And its popularity means there might be all sorts of payloads launched on an Atlas with a Centaur upper stage which might then be one step away from using Jupiter to expand their mission capability, or restore their mission capability.

The satellite would have to be designed for serving first.

A Jupiter-class tug on top of ULA's distributed launch architecture could easily approach von Braun's vision of assembling a Mars-bound spaceship in earth orbit, but cheaply.  It points the way toward far more practical commercial station maintenance that doesn't require 24/7 staffing by humans.

The ISS is already capable of having it's robot arm do things commanded from the ground.  And the assemble may or may not need an tug(The thing could have docking ports or arms).  Stations also don't need 24/7 staffing by humans. They are just sate-lights capable of supporting human life.
   

[manboy]

Those science missions do those complex tasks because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans. I'm skeptical Jupiter could compete with those vehicles on a cost basis.

They represent developed, proven hardware that DOES DO THOSE THINGS. And they already function reliably over longer duration than the ENTIRE LIFE OF 10's to 100's of "deliveries".

Since one of them is needed to perform the function of 10 or 100 or more, perhaps the cost basis isn't the same as a one-shot?

They do some of those things but they don't capture, perform vessel hand over, fuel transfer or rendezvous with other vehicles. The complex tasks they do are done because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans.

Depends on the time it takes to recover the cost and/or prove the capability. Break even is typically what you look at, and that was around 10 or so.

Minimum amount of missions to be awarded is 6.

Implicit in the form used to eliminate the benefit as risk. I.e. that fewer dependent operations make for less mission risk, thus by induction the fewest operations (i.e. what we have now) is optimum, so you can't improve upon that. QED.

I run into this all the time. It's tiresome.

Business model changes in how we handle space are now essential to the business is my top level point here. This example with Jupiter is otherwise unremarkable.

You haven't even proven there's any benefit. What's the advantage of Jupiter over Dragon? They both carry internal and external cargo. The only thing that get's thrown away on Dragon is the radiator and solar arrays. There are also many other in-orbit refueling proposals that are vastly superior to Jupiter.

[a_langwich]

I was thinking of an somewhat less passive cargo container. One that has some propulsion and station keeping capability.

Again, you've just included most of the expense of the tug.  The guidance and control, propulsion, communication and the power system to run them are the pieces on which Jupiter is saving cost by only launching once.  It can do this because it can take advantage of Centaur's continued availability after orbital insertion, and Centaur's proven version of all these components.  Orbital currently only ends up with a dead solid beneath it after launch, so changing that would be necessary. 

Maybe Orbital-ATK's solid stage is so cheap they can afford to include another GEOStar-based platform to be expended, in addition to the one for Cygnus.  The economics (how much you are saving, and how much payload penalty there is) and deltaV aren't as good, but as you say that is at least partly balanced by the cheaper launch vehicle.  The original Antares was underpowered even for CRS-1, so it couldn't support this concept, but maybe the full capacity of Antares II would have enough mass capability to do it.

Questionable that it makes sense now. Risky but there are not enough other carriers to mitigate it. It's one thing when you have enough cargo coming from other companies, but right now there are only two and I doubt NASA would select more than 2-3 companies for this contract.

This is irrelevant.

And the reason why we use modularity in transport on earth is because it give an clear benefit for operations involving that cargo(loading/unloading, switching between vehicles, switching between modes of transport). 

Yes!  Only I think you have fixated on the intermodel container analogy.  Think of a tractor-trailer rig.  One engine and control piece can be attached to many different cargo carriers, and it is still very useful even if one company makes all of those cargo containers.  Being able to unload one trailer, while the tractor is going to pick up another one, is useful.  That usefulness still applies even if your competitors are using moving vans, and they don't have trailers of their own that you can tow around.  If you are filling your trailers with trash and burning them up, it makes tremendous sense not to burn up the tractor portion with the trailer, and the more trailers you burn up the more you've saved by not expending the tractor.

Here Jupiter is attempting reuse via modularity, but the dumb cargo container is attached to an modified expensive upper stage(Centaur), launched by an expensive rocket(Atlas or Delta).

Not sure what you mean by "attached".  It rides on top of a Centaur, true, like any payload, but no more.  You have no idea what a Centaur costs relative to any other upper stage, so you really shouldn't assume.  And you aren't paying any extra for that Centaur, above your launch cost.

Granted, the Atlas V is a premium ride into orbit these days, not the cheapest.  But it is cheap enough that Orbital just bought two flights to help fill out their CRS-1 obligations, so it's not that outrageous either.  A Falcon+Dragon flight costs about $140 million for CRS-1, and Antares+Cygnus ran about $238 million.   

I think it's likely you could build a Jupiter-like architecture that would be price competitive with those even on an Atlas, but how LM chose to try to recover its R&D costs and price their idea, I don't know.  I know what the rumors say, and it seems like many on this forum are trying to use their logic to justify that assumed reality.  LM may well have assumed they could command too high a price, or decided on too large a profit margin, or decided to recover their development costs on too quick a time frame.  But I don't know.

Who said a Jupiter tug couldn't make it to GEO?  And its popularity means there might be all sorts of payloads launched on an Atlas with a Centaur upper stage which might then be one step away from using Jupiter to expand their mission capability, or restore their mission capability.

The satellite would have to be designed for serving first.

Well that was what I had in mind, that the satellite manufacturer and satellite operator would see the possibilities and jump to take advantage of them.  But strictly speaking, DARPA and various other organizations (NASA too, I think) have looked at satellite servicing even on satellites not designed for it.  Refuelling seems to be possible.  Certainly it could tug a prematurely failed satellite to a disposal orbit, although the more deltaV I wave my hands around, the more likely it would want swapping in an electric thruster system.   

In the recent Intelsat / Russian Luch satellite deal, one wonders what would happen if Intelsat had a Jupiter tug come nearby, and call up and offer the Russians a friendly tow to wherever they meant to be going before they surely lost control and it wandered too close to commercial sats?  Putin seems to respond well to the big stick approach, it just seems he hasn't been shown it quite enough.

A Jupiter-class tug on top of ULA's distributed launch architecture could easily approach von Braun's vision of assembling a Mars-bound spaceship in earth orbit, but cheaply.  It points the way toward far more practical commercial station maintenance that doesn't require 24/7 staffing by humans.

The ISS is already capable of having it's robot arm do things commanded from the ground.  And the assemble may or may not need an tug(The thing could have docking ports or arms).  Stations also don't need 24/7 staffing by humans. They are just sate-lights capable of supporting human life.
   

You missed the key word commercial station.  Yes, the ISS has several Canadian arms (in response to rather ignorant comments made by some earlier in the thread about LM going outside the country for parts, as if any of NASA's big articulated arms had come from anywhere other than Canada, and as if the US had any knowledge base on arms that needed preserving by means of a cargo vessel). 

But for a commercial station, or multiple mini stations, having a tug with an arm servicing multiple small standalone facilities might be very handy.   Having that arm mounted on a free-flying platform with its own thrusters and attitude control and power gives some of the flexibility of the way the ISS can move its arms around to different places, but without all of the expense and design complexity of the tracks.  An inflatable commercial station, for example, might not find it convenient to mount the hard structure for a track around its perimeter.   If you add free flyers in formation, Jupiter allows you to send an arm to a non-contiguous part of ISS and service it.

Yes, it's true a spacecraft could self-assemble, but again you are missing the way the tug allows you to separate out the expensive parts that do inertial control, station maintenance, attitude control, docking, and manipulation.  You can use one tug for multiple assemblies.  You know, that's the reason each segment of ISS doesn't have its own thrusters and attitude control and comm and power and certainly not arms:  it had the shuttle as a tug to help assemble them.

And lastly, you missed the key word maintenance.  Things break, and humans must then get involved.  Having an arm on a mobile platform, with which you might be able to go around and fix things telerobotically, might allow you to dispense with some EVAs and associated training and equipment. 

At ISS they would freak at the thought of a free flyer moving around in really close proximity, and they've spent many many billions to design other ways of accomplishing this (multiple arms, the track, constant human presence, extensive EVA training, etc).  So a station maintenance capability is not likely to be useful for ISS.  But a commercial station might find using something like Jupiter was a cheaper way to do things, especially if they had a Jupiter hanging around for cargo resupply.

[a_langwich]

You haven't even proven there's any benefit. What's the advantage of Jupiter over Dragon? They both carry internal and external cargo. The only thing that get's thrown away on Dragon is the radiator and solar arrays. There are also many other in-orbit refueling proposals that are vastly superior to Jupiter.

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

And, whether or not NASA chooses to try recycling an already-used Dragon, every single pound of Dragon must be launched into space every time cargo is flown.

For Jupiter, the solar arrays and batteries, the propulsion and attitude control system, the guidance and communication computers and systems, the rendezvous sensors, all get launched once.  Subsequent launches are purely dumb aluminum cans.

Dragon is a bad choice for comparison, because it's a completely different vehicle with many systems involved in reentry capability.  Dragon's down mass ability is a substantial drag on its upmass capability (sorry).  Let's look at Orbital's Cygnus:  Cygnus is the marriage of an Orbital GEOStar satellite core with an Alenia keg.  In the Jupiter architecture, the equivalent of the Orbital GEOStar base is launched once and stays in space, and only the kegs get launched after that.  Not only have you saved the cost of building another GEOStar base equivalent, but you've saved however many thousands of dollars for each kg it weighs in launch costs.  Multiplied by how many times you fly.

Then, beyond the price savings, you get an independently capable tug in space.  After Dragon is launched, all it can do is maneuver up to ISS and wait for to berth it.  Jupiter has an arm, it can manipulate things...that opens the door to all sorts of shenanigans, at the ISS end or in the general neighborhood of ISS, at the Centaur end where it's used to swap kegs and refuel itself, and ultimately in all sorts of future NASA missions.

[ChrisWilson68]

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

That's only because NASA told SpaceX to bid for a new Dragon every flight on CRS1.  Nobody outside SpaceX and NASA knows if the SpaceX CRS2 bid includes reflying Dragons.

[MattMason]

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

That's only because NASA told SpaceX to bid for a new Dragon every flight on CRS1.  Nobody outside SpaceX and NASA knows if the SpaceX CRS2 bid includes reflying Dragons.

My understanding from another thread indicates that components of flown Dragons are being reused in later CRS flights.

[baldusi]

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

That's only because NASA told SpaceX to bid for a new Dragon every flight on CRS1.  Nobody outside SpaceX and NASA knows if the SpaceX CRS2 bid includes reflying Dragons.

My understanding from another thread indicates that components of flown Dragons are being reused in later CRS flights.

I don't want to get into hijacking the LM thread, but SpaceX failed at its first attempt of reusability in everything (rocket, capsules, etc). Look their evolution from F1 to F9 v1.1 Full Thrust (plus the Grashopper program). Look at Dragon v1, V1.5 and v2. And yet they haven't started with the DragonFly project.
Do you think that LM could hit the right trade in reusability on the first try and gamble your 100B+ project utilization on that? That's the core issue with LM Jupiter/Exoliner proposal. They want to do a high risk/high payoff experiment on the final days of a fully operational multi-decade multi-billion USD project.

[manboy]

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

I was referring to future variants which is as real as Jupiter is at this point.

For Jupiter, the solar arrays and batteries, the propulsion and attitude control system, the guidance and communication computers and systems, the rendezvous sensors, all get launched once.  Subsequent launches are purely dumb aluminum cans.

What's the mass breakdown?

Dragon is a bad choice for comparison, because it's a completely different vehicle with many systems involved in reentry capability.  Dragon's down mass ability is a substantial drag on its upmass capability (sorry).

It's a great comparison because they it accomplishes the same goals of Jupiter, has greater re-use, has significantly less complex mission procedures, is most likely cheaper and even has the ability to return cargo to Earth.

Of course it's a very different vehicle but that's what makes it superior and at the end of the day they're both competing for the same Commercial Cargo program.

Then, beyond the price savings, you get an independently capable tug in space.  After Dragon is launched, all it can do is maneuver up to ISS and wait for to berth it.  Jupiter has an arm, it can manipulate things...that opens the door to all sorts of shenanigans, at the ISS end or in the general neighborhood of ISS, at the Centaur end where it's used to swap kegs and refuel itself, and ultimately in all sorts of future NASA missions.

Can you please explicitly list the advantages of a ISS cargo resupply vehicle having its own arm?

[savuporo]

Can you please explicitly list the advantages of a ISS cargo resupply vehicle having its own arm?

Rendezvous and berthing with relatively simple cargo modules and other spacecraft in space. In theory it could deploy and retrieve free-flying co-orbiting experiments from ISS without its own significant propulsive capabilities.

It could potentially operate as an independent robotic orbital assembly and servicing platform.

From what i understand, the propellant transfer and robotic capabilities would effectively have been up-scaled Orbital Express ASTRO satellite. OrbEx demonstrated monoprop hydrazine transfers, which is the spacecraft bus proposed here is flying on, too. OrbEx also demonstrated orbital replacement units of batteries and other things IIRC.

[Space Ghost 1962]

Those science missions do those complex tasks because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans. I'm skeptical Jupiter could compete with those vehicles on a cost basis.

They represent developed, proven hardware that DOES DO THOSE THINGS. And they already function reliably over longer duration than the ENTIRE LIFE OF 10's to 100's of "deliveries".

Since one of them is needed to perform the function of 10 or 100 or more, perhaps the cost basis isn't the same as a one-shot?

They do some of those things but they don't capture, perform vessel hand over, fuel transfer or rendezvous with other vehicles.

Yes, thank you Mr Flat Earth. No exact match of flown craft. However, Progress has done this for decades. As well as using Soyuz as a tug (an alternative approach for same, and even cheaper if you want to pay for the service).

The complex tasks they do are done because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans.

This virtue is actually a curse, not a virtue.

Both for maturing capabilities for missions that make use of them, and for improving aggregate mission success, because instead of optimizing short chains of consequential actions, you optimize on the larger ones. With ever more complex systems that we fly, at some point we fool ourselves by bounding risk in such a way as you describe, because of the combinatorial explosion of the "simple" mission is not necessarily significant from the "complex" mission, due to the way the factors come together (Boeing has discovered this in airlines FYI, as Intel did with Pentium a decade plus back).

Depends on the time it takes to recover the cost and/or prove the capability. Break even is typically what you look at, and that was around 10 or so.

Minimum amount of missions to be awarded is 6.

Yes, I know. Tough for evolving HSF resupply. Not my issue.

Implicit in the form used to eliminate the benefit as risk. I.e. that fewer dependent operations make for less mission risk, thus by induction the fewest operations (i.e. what we have now) is optimum, so you can't improve upon that. QED.

I run into this all the time. It's tiresome.

Business model changes in how we handle space are now essential to the business is my top level point here. This example with Jupiter is otherwise unremarkable.

You haven't even proven there's any benefit.

Nor did I prove a benefit of a Pathfinder rover before flying one. Yet we did fly one, and we don't do Mars landers anymore. Hundred examples like this.

What's the advantage of Jupiter over Dragon? They both carry internal and external cargo. The only thing that get's thrown away on Dragon is the radiator and solar arrays. There are also many other in-orbit refueling proposals that are vastly superior to Jupiter.

As I said, I'm not an advocate. But you said:

It was a terrible proposal. It was unnecessarily complex and the majority of the hardware would have been manufactured by non-U.S. aerospace companies.

And asked:

I don't understand why so many people feel the need to defend this three-legged dog.

To bring this to a quick end, I'll cut to the chase and go to an extremely simplified Jupiter-like system to make my point (we'll assume Jupiter "additions" to this are LMT "fluff" that does not concern this discussion).

 * Unpowered pressure vessel with self powered environmental as part of cargo as needed. Perhaps no shroud as part of lowest cost (to integrate as well) structure, possibly all carbon fiber with domestic automated fabrication.

 * Handoff from US to existing VV with significant prop reserves (like with Progress, Soyuz, Dragon Rider, ...) - various hard attach and operations outside of KOS. No modification of US.

 * Typical cargo entry to KOS and berthing operations, avoiding the usual issues (incl plume impingement). VV recovery following.

 * Typical deberth following VV operations to on station, as well as escape of KOS with VV. Various deorbit of unpowered cargo pressure vessel, including perhaps a tether. VV recovery.

Now assume the details of the above are chosen in such a way that they aren't the stopper for this approach.

What are you left with? Minimal parasitic mass to payload to HSF facility, in this case ISS. Lowest cost to integrate, quickest payload to process, lowest risk to launch (mostly packing, spin table, etc). On orbit assets have operations risk/cost (staff/oversight), consumables (props, pressurant, ...) consumption.

You also gain maximum launcher diversity. You might even make this "extrudable" to considerable extension beyond approaches like Cygnus to scale up per launcher capacity.

Now, like with the containerized cargo referenced earlier, you can reuse the infrastructure for other HSF payloads.
Lets say you have a component/consumable that does not fit an existing VV cargo, either due to risk or capacity given the bus and shroud. Since you don't have bus or shroud, you don't have the limitations of such.

So what you get as advantage is pressurized payload scaling with launch cost, fast resupply missions (in case of failure), more reliable launch (no bus means no launch risk from bus), and the capability to launch highest risk payloads (margin, volume, hazards) limited by only the launcher itself.

And, as we take HSF further beyond LEO, parasitic mass costs more the higher / further / faster we go. If we get to optimum in LEO, then we can carry that outward with us in terms of margin and mission scope/size/duration.

add:
Almost forgot. All of the items I covered above are a direct translation of the containerized cargo business proven in the case studies, so none of this is hypothetical but proven over 50 years of business. More proven than any space architecture scaling ever. So you don't need my help to figure this one out, go argue with Wharton about it.

It also is key to American economic progress over that time.

[ChrisWilson68]

Everything gets thrown away on Dragon.  Oh, sure, it's sitting in a warehouse somewhere, or in some unused space at Hawthorne, but the next time a resupply flight goes up, it's a new Dragon.

That's only because NASA told SpaceX to bid for a new Dragon every flight on CRS1.  Nobody outside SpaceX and NASA knows if the SpaceX CRS2 bid includes reflying Dragons.

My understanding from another thread indicates that components of flown Dragons are being reused in later CRS flights.

I don't want to get into hijacking the LM thread, but SpaceX failed at its first attempt of reusability in everything (rocket, capsules, etc).  Look their evolution from F1 to F9 v1.1 Full Thrust (plus the Grashopper program). Look at Dragon v1, V1.5 and v2.

There's a big difference between failing to achieve something and still being on the road to achieve it, even if that road has taken longer than planned.

And yet they haven't started with the DragonFly project.

Yeah, because NASA is risk-averse and told them to focus on doing things the way they've been done in the past first.  Since NASA is paying the bills, I think we can forgive SpaceX for giving them what they ask for.

Do you think that LM could hit the right trade in reusability on the first try and gamble your 100B+ project utilization on that? That's the core issue with LM Jupiter/Exoliner proposal. They want to do a high risk/high payoff experiment on the final days of a fully operational multi-decade multi-billion USD project.

Not all reusability is created equal.  Reusability of F9 and Dragon is difficult because they have to re-enter the atmosphere.  Remove that and you basically have a static fire.  And SpaceX had no problem mastering re-use after a static fire.

Re-usability of Jupiter is totally different.  It doesn't have to go through the ordeal of re-entry.  It just stays in orbit and continues operating -- just like hundreds of satellites have been doing for decades.  The kind of re-usability Jupiter is talking about is a solved problem.

[manboy]

Can you please explicitly list the advantages of a ISS cargo resupply vehicle having its own arm?

Rendezvous and berthing with relatively simple cargo modules and other spacecraft in space. In theory it could deploy and retrieve free-flying co-orbiting experiments from ISS without its own significant propulsive capabilities.

It could potentially operate as an independent robotic orbital assembly and servicing platform.

From what i understand, the propellant transfer and robotic capabilities would effectively have been up-scaled Orbital Express ASTRO satellite. OrbEx demonstrated monoprop hydrazine transfers, which is the spacecraft bus proposed here is flying on, too. OrbEx also demonstrated orbital replacement units of batteries and other things IIRC.

I crossed out everything that appeared to be irrelevant to the question asked. Is the ability to retrieve free-flying experiments in ISS proximity a desired capability?

Those science missions do those complex tasks because there is no other way to achieve their mission goals. It's not comparable because other vehicles have even greater re-usability while accomplishing the same goals but with significantly less complex mission plans. I'm skeptical Jupiter could compete with those vehicles on a cost basis.

They represent developed, proven hardware that DOES DO THOSE THINGS. And they already function reliably over longer duration than the ENTIRE LIFE OF 10's to 100's of "deliveries".

Since one of them is needed to perform the function of 10 or 100 or more, perhaps the cost basis isn't the same as a one-shot?

They do some of those things but they don't capture, perform vessel hand over, fuel transfer or rendezvous with other vehicles.

Yes, thank you Mr Flat Earth. No exact match of flown craft.

It wasn't even in the same ballpark. The crafts you were comparing had hardly any similarities.

Depends on the time it takes to recover the cost and/or prove the capability. Break even is typically what you look at, and that was around 10 or so.

Minimum amount of missions to be awarded is 6.

Yes, I know. Tough for evolving HSF resupply. Not my issue.

It is if you're using it as the foundation of your argument.

Nor did I prove a benefit of a Pathfinder rover before flying one. Yet we did fly one, and we don't do Mars landers anymore. Hundred examples like this.

The benefit of a rover vs. a lander is obvious.

Almost forgot. All of the items I covered above are a direct translation of the containerized cargo business proven in the case studies, so none of this is hypothetical but proven over 50 years of business. More proven than any space architecture scaling ever. So you don't need my help to figure this one out, go argue with Wharton about it.

And they apparently don't need to be modified for spaceflight.

[savuporo]

I crossed out everything that appeared to be irrelevant to the question asked. Is the ability to retrieve free-flying experiments in ISS proximity a desired capability?

Yes.

[Danderman]

Can you please explicitly list the advantages of a ISS cargo resupply vehicle having its own arm?

It could berth at CBMs where the station arm would have issues, say at the end of a hypothetical Node 4.

Or help solve problems where the station arm is involved in another operation at the time of berthing.

Allows passive containers to be used to carry cargo, with an intermediate berthing prior to arrival at the station.