NASA SLS/Orion/Payloads

[Canopus]

2 minutes ago, sevenperforce said:

EM-1 can be done in two launches with Delta IV Heavy or Falcon Heavy. EM-2 can be done in 3 launches with Falcon Heavy or 4 with Delta IV Heavy. And I believe Europa Clipper can be done via direct Hohmann on Falcon Heavy with two launches.

Only from pure point of view of mass, since as already stated, without some major changes to the Upper stages, complex multilaunch mission like that aren't possible with Delta IV or Falcon Heavy.

[sh1pman]

9 minutes ago, Canopus said:

Only from pure point of view of mass, since as already stated, without some major changes to the Upper stages, complex multilaunch mission like that aren't possible with Delta IV or Falcon Heavy.

Not really major, just a payload mating adapter for FH S2. Launch a Europa Clipper on F9 and one FH with no payload and this custom adapter. The S2 will have something like 90t of propellant once in orbit. Dock it with the Clipper, do the burn, decouple the S2. Done.

[tater]

One aspect of unmanned spaceflight that has not internalized launch cost changes is spacecraft mass, reliability, and cost interactions.

Europa clipper is huge, particularly with a lander, hence SLS. It’s also insanely pricey.

What mass can FH throw direct to the he same targets? Instead of all the eggs in one basket, why not make a simple bus (or reuse and extant design), then bang a few out. The goal would be radically reduced cost. All would have power, high gains, radios, etc in common. Think bigger cubesats. Could you make such a craft for some fraction of the X billion it costs to launch SLS, then launch a few of them? Send the lander by itself, for example.

[Canopus]

2 minutes ago, sh1pman said:

Not really major, just a payload mating adapter for FH S2. Launch a Europa Clipper on F9 and one FH with no payload and this custom adapter. The S2 will have something like 90t of propellant once in orbit. Dock it with the Clipper, do the burn, decouple the S2. Done.

This isn't KSP where you can simply slap a docking node in front and a few RCS thrusters on the side of a stage and call it a day. Rendezvous and autonomous docking (something which hasn't been done by SpaceX yet) means you have to build a whole new stage. Essentially  a space tug. It's not easy

6 minutes ago, tater said:

Europa clipper is huge, particularly with a lander, hence SLS. It’s also insanely pricey.

What mass can FH throw direct to the he same targets? Instead of all the eggs in one basket, why not make a simple bus (or reuse and extant design), then bang a few out. The goal would be radically reduced cost. All would have power, high gains, radios, etc in common. Think bigger cubesats. Could you make such a craft for some fraction of the X billion it costs to launch SLS, then launch a few of them? Send the lander by itself, for example.

The Lander is actually long gone from Europa Clipper.

[sh1pman]

1 minute ago, Canopus said:

This isn't KSP where you can simply slap a docking node in front and a few RCS thrusters on the side of a stage and call it a day. Rendezvous and autonomous docking (something which hasn't been done by SpaceX yet) means you have to build a whole new stage. Essentially  a space tug. It's not easy

If there was such a demand, they’d do it. They’re going to need rendezvous and autonomous docking for BFR anyway. If BFR wasn’t in the plans, it would even be a sensible thing to do, along with extending S2 and maybe trying orbital refueling with it.

[PB666]

2 hours ago, Canopus said:

Both refueling and orbital maneuvers like rendezvous with already launched cargo would basically require a new upper stage for Falcon to be developed, something which doesn't seem to be on the plan for SpaceX. That's why i think a more realistic SLS replacement could be Vulcan ACES where all those capabilities are already going to be included.

I don't think either CST-100 or Dragon 2 are able to carry out missions long enough and don't have the capacity to maneuver to be of any real use beyond low earth orbit. So Orion might even outlive SLS and fly on other LV's.

By the time Vulcan is ready to launch ULA may be out of business.

[Starman4308]

55 minutes ago, Canopus said:

This isn't KSP where you can simply slap a docking node in front and a few RCS thrusters on the side of a stage and call it a day. Rendezvous and autonomous docking (something which hasn't been done by SpaceX yet) means you have to build a whole new stage. Essentially  a space tug. It's not easy

Is it $2 billion "not-easy"? SpaceX can literally afford to send up multiple Dragons for the sole purpose of testing autonomous rendezvous and docking for the price differential between a pair of Falcon Heavy launches and a single SLS.

And that's ignoring the option I'd favor, which is to simply abandon the direct Hohmann transfer and launch it on an EVJ trajectory. Sure, it takes a few more years, but it's an unmanned mission: mission costs don't go up a huge deal because of that.

[sevenperforce]

1 hour ago, Canopus said:

This isn't KSP where you can simply slap a docking node in front and a few RCS thrusters on the side of a stage and call it a day. Rendezvous and autonomous docking (something which hasn't been done by SpaceX yet) means you have to build a whole new stage. Essentially  a space tug. It's not easy

Dragon can already perform autonomous rendezvous. Dragon 2 and Orion will both be able to autonomously dock. Doing the same with Europa Clipper or the DSG PPM is just a matter of software, since both Europa Clipper and the PPM will have all the necessary hardware.

All the Falcon upper stage needs to do is use its cold gas thrusters for pointing, which is already within the Falcon 9 user guide available functions. Bolting an IDA onto a Falcon upper stage is hardly challenging.

[PB666]

1 hour ago, tater said:

Mission duration could be achieved for cst-100 or D2 via docking with a hab module in LEO, and I suppose both companies could make proper service modules.

It could be possible to launch  capsule, and follow up with FH lofting a hab (not dense) with loads of remaining propellant, and that gets used to push the pair wherever within the limits S2 coast times.

All that said, I don’t see FH replacing SLS, because I don’t see many useful SLS missions worth replacing.

Right, all F9 and a single flight would need to launch a multiport hub with a guidance system and RCS fuel and RCS thrusters. If it got that then anything with a docking port could be 'potentially' fuel through the hub to anything else. Its smarter to do that anyway because you can have a flight with a single two intercyclinder tanks that one can load in a single trip, then add kerosene (or methane) in another trip and another one with oxygen. The cylinder itself could have its own solar panels and oxygen/methane recycling system. The trick side of this is refueling what needs to go into deep space. This is much more difficult for H2 rockets because of the recycling problem. (albeit O2 and methane are also hard). This is not the 1960s where soyuz botched several flights trying to dock, computers can do essentially everything now. SpaceX does even need to build the hub, they could contract it out to agencies that have previously built for nasa. Just about anything would be cheaper than the DSG (or whatever its now called)

But to the point, other than the proof of concept missions, there is nothing for a SX docking hub to interact with except other SX vehicles (there are far fetched scenarios like SX providing fuel for other public sector space agencies). But the game is still young, we have to see what develops over the next year or so.

[sevenperforce]

38 minutes ago, PB666 said:

Right, all F9 and a single flight would need to launch a multiport hub with a guidance system and RCS fuel and RCS thrusters. If it got that then anything with a docking port could be 'potentially' fuel through the hub to anything else. Its smarter to do that anyway because you can have a flight with a single two intercyclinder tanks that one can load in a single trip, then add kerosene (or methane) in another trip and another one with oxygen. The cylinder itself could have its own solar panels and oxygen/methane recycling system. The trick side of this is refueling what needs to go into deep space. This is much more difficult for H2 rockets because of the recycling problem. (albeit O2 and methane are also hard). This is not the 1960s where soyuz botched several flights trying to dock, computers can do essentially everything now. SpaceX does even need to build the hub, they could contract it out to agencies that have previously built for nasa. Just about anything would be cheaper than the DSG (or whatever its now called)

But to the point, other than the proof of concept missions, there is nothing for a SX docking hub to interact with except other SX vehicles (there are far fetched scenarios like SX providing fuel for other public sector space agencies). But the game is still young, we have to see what develops over the next year or so.

This is off-topic for SLS, but is there any commercial case to be made for a LEO tug/station/hub for sending payloads from LEO to GTO or to GEO? Could a robotic orbital assembly/mating station turn a profit?

[tater]

SLS could launch a huge tug, I suppose, but the cadence is so low, there'd be nothing left propellant wise by the time it flew something to get tugged.

Edited March 3, 2018 by tater

[_Augustus_]

11 minutes ago, tater said:

SLS could launch a huge tub, I suppose, but the cadence is so low

I'm hoping this is a typo?

[tater]

2 minutes ago, _Augustus_ said:

I'm hoping this is a typo?

Tug

I'm enjoying this $50 pinot someone gave us, though.

[PB666]

4 hours ago, sevenperforce said:

This is off-topic for SLS, but is there any commercial case to be made for a LEO tug/station/hub for sending payloads from LEO to GTO or to GEO? Could a robotic orbital assembly/mating station turn a profit?

It would have to all be docking ports, the shuttle is gone, unless they spent 5 years fashioning a replacement robotic arm on some device.

[Canopus]

6 hours ago, PB666 said:

By the time Vulcan is ready to launch ULA may be out of business.

In 2020? I somehow doubt that.

6 hours ago, Starman4308 said:

Is it $2 billion "not-easy"? SpaceX can literally afford to send up multiple Dragons for the sole purpose of testing autonomous rendezvous and docking for the price differential between a pair of Falcon Heavy launches and a single SLS.

And that's ignoring the option I'd favor, which is to simply abandon the direct Hohmann transfer and launch it on an EVJ trajectory. Sure, it takes a few more years, but it's an unmanned mission: mission costs don't go up a huge deal because of that.

They could but since they are a launch provider looking to maximise profits they won‘t since there is no Payload that would necessitate such capabilities. You are right about Europa Clipper though. Makes more sense to launch it the traditional way. Even if that takes 6 years.

[PB666]

5 hours ago, Canopus said:

In 2020? I somehow doubt that.

They could but since they are a launch provider looking to maximise profits they won‘t since there is no Payload that would necessitate such capabilities. You are right about Europa Clipper though. Makes more sense to launch it the traditional way. Even if that takes 6 years.

What makes you think it will be ready to launch in 2020? The RL10 engines they are going to put on the Centaur second stage is likely to be the RL10C-1, they are still pretty much in early testing.

Quote

The engine was already in its third year of development by Blue Origin, and ULA said it expected the new stage and engine to start flying no earlier than 2019. Fleischauer, Eric (7 February 2015). "ULA's CEO talks challenges, engine plant plans for Decatur". Decatur Daily. Retrieved 2015-04-17.

Quote

A delay was announced pushing first launch back from 2019 to mid-2020.^[5] Also announced was an upgrade to the Centaur 2nd stage to include 4 RL10 engines in lieu of 1.^[25] This version of the 2nd stage will be called Centaur V

The RL10C-1, C-2 is supposed to replace the RL10B-2 in multiengine configurations were total diameter is less than 6 meters.
 

 

[Canopus]

Right there in your post it quotes the Vice President of ULA who expects first launch of Vulcan in mid 2020. Even if its delayed for one or two years, it doesn‘t make it any more plausible that ULA would go out of business. The whole idea is ridiculous.

[DDE]

50 minutes ago, Canopus said:

The whole idea is ridiculous.

ULA has LockMart and Boeing behind them. They’re virtually unsinkable so long as there even a slight chance of them returning to profitability in the mid-term.

[PB666]

1 hour ago, Canopus said:

Right there in your post it quotes the Vice President of ULA who expects first launch of Vulcan in mid 2020. Even if its delayed for one or two years, it doesn‘t make it any more plausible that ULA would go out of business. The whole idea is ridiculous.

Maybe, but at the rate they are performing they will not hold up long to the competitive threat from SX.

My base assumption here is that they need 4 RL10C-1 engines. That the Aerojet Rocketdyne will not release the 4 until they have at least 6 in the supply chain and that is the subtraction for those already dedicated to other launches. My assumption is based on the fact that the RL10B-2 supply chain is retarded and the C-1 supply chain given its novelty and the time required to build the B-2 will also be retarded. If Rocketdyne picks up the pace and begins cranking these things out they will be on schedule. But I factor into the supply process the typical lags of the shuttle period when suppliers announced when something would be available and when it was actually available for integration.

Edited March 3, 2018 by PB666

[DAL59]

On 3/2/2018 at 7:01 PM, Canopus said:

The Lander is actually long gone from Europa Clipper.

WHAT!  Whats the point even?  Just wasting money?  Really, the fact is, you can sense biomarkers as much as you want, but you cannot actually find life unless you land.  Why not send just a lander if a sat and a lander is too expensive? What is stopping NASA from landing on Europa?  Is this 2010- the year we make contact?   

[Starman4308]

34 minutes ago, DAL59 said:

WHAT!  Whats the point even?  Just wasting money?  Really, the fact is, you can sense biomarkers as much as you want, but you cannot actually find life unless you land.  Why not send just a lander if a sat and a lander is too expensive? What is stopping NASA from landing on Europa?  Is this 2010- the year we make contact?   

Because it'd be an amazingly expensive thing to try when we don't yet know much about the surface of Europa. You'd need something to propulsively land on Europa's surface, since there's no atmosphere of note, that means Good Old Chemical Rocket Propulsion, which would again be expensive. All on a moon we haven't characterized all that well yet.

It does not help that Jupiter's gravity well is enormous, and just braking to match Europa's velocity takes a hefty chunk of delta-V.

I agree with the current mission profile: multiple flybys (which helps reduce time spent in Jupiter's tremendous probe-killing magnetosphere), and then consider sending a lander separately, using the data obtained from the Europa Clipper to be much more confident about how to design the lander.

Also, you're ignoring everything else the Clipper will be doing in favor of chasing after the utterly minute chance it might have life (and if so, it's probably buried deep inside the ice, where you'd need a really, really capable lander to get at!).

[DDE]

3 hours ago, Starman4308 said:

Also, you're ignoring everything else the Clipper will be doing in favor of chasing after the utterly minute chance it might have life (and if so, it's probably buried deep inside the ice, where you'd need a really, really capable lander to get at!).

*ponders a Curiosity-style skyhook carrying a CASABA-HOWITZER charge to blast through the ice*

[Nibb31]

5 hours ago, DAL59 said:

WHAT!  Whats the point even?  Just wasting money?  Really, the fact is, you can sense biomarkers as much as you want, but you cannot actually find life unless you land.  Why not send just a lander if a sat and a lander is too expensive? What is stopping NASA from landing on Europa?  Is this 2010- the year we make contact?   

Do you have any idea how hard it is to land on Europa, and how much dV you need to carry ?

[YNM]

1 hour ago, Nibb31 said:

Do you have any idea how hard it is to land on Europa, and how much dV you need to carry ?

Well worth the hassle I think. You know how good NH was with Pluto.

[Canopus]

14 minutes ago, YNM said:

Well worth the hassle I think. You know how good NH was with Pluto.

NH just shows how much information you can gather from a single flyby. Now imagine multiple flybys of Europa. The lander they had invisioned wouldn‘t have penetrated the ice more than a meter or something so the idea that it could have found Europan sea slugs is wrong anyway. In the end the Orbiter would have collected more data of the moon than the lander ever could.