Forum designs new rocket to replace the SLS

[ZooNamedGames]

I was talking to @tater a few days back about the SLS when he mentioned an interesting question;

Quote

 

Specifically,

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if you took the XX billions to develop SLS, then offered half as a lump sum for a working replacement, I wonder what the result would be?

So I was curious what we forumers could come up with as an alternative to NASA's Space Launch System (SLS) within the budget of 5 billion dollars with our goal and purpose of our new rocket being to ferry larger payloads than 70,000kg. The idea being to provide the largest launcher available for those who require it. Making it modular as far as rocket segments would also be ideal however not required.

So, let me know what your designs and concepts would be for a 5 billion dollar rocket.

[_Augustus_]

[NSEP]

I made a rocket in RO that can send 250tons to LEO using real engines, but thats probably too expensive, simple and big to be a real thing.

But i will maybe get to making something. If i have time.

[ZooNamedGames]

9 minutes ago, _Augustus_ said:

Just pointing out that UA is intending to filter out their Atlas and Delta rocket families with their new Vulcan rocket series and yes, I know there is issues around getting the engine right now but that doesn't avoid that the Delta and Atlas systems are due an update.

[magnemoe]

Well an 4 booster version of falcon heavy makes sense, perhaps even an 6 booster one. 
Its basically an strengthen core with more attachments, you would also need to reinforce the upper stage, no crossfeed as its complex, but I would shut of engines, probably turn off the core engines during flight, then trim back on the second set of boosters so they burn longer than the first set. 
for the 6 booster extreme edition it would probably have to be all expendable because of room around boosters and complexity. You could probably forget to recover the last two anyway. 
All this would be cheap, for an 2+2+1 test you could  recover the 4 boosters. 

Option for lengthened core and perhaps an new upper stage using methane who would be nice for an moon landing. 
An heavy version of new Glen would be next step but farther ahead. 

[ZooNamedGames]

3 minutes ago, magnemoe said:

Well an 4 booster version of falcon heavy makes sense, perhaps even an 6 booster one. 
Its basically an strengthen core with more attachments, you would also need to reinforce the upper stage, no crossfeed as its complex, but I would shut of engines, probably turn off the core engines during flight, then trim back on the second set of boosters so they burn longer than the first set. 
for the 6 booster extreme edition it would probably have to be all expendable because of room around boosters and complexity. You could probably forget to recover the last two anyway. 
All this would be cheap, for an 2+2+1 test you could  recover the 4 boosters. 

Option for lengthened core and perhaps an new upper stage using methane who would be nice for an moon landing. 
An heavy version of new Glen would be next step but farther ahead. 

Possibly, but reusability limits range. The idea is we're sacrificing reuse for range.

Plus... am I the only one who thinks that Elon's solution to increased payload mass is just a bit too Kerbalish? In that he goes for the asparagus staging route... I mean it works but it is a bit Kerbal.

[Gaarst]

/thread

[ZooNamedGames]

8 minutes ago, Gaarst said:

/thread

Too bad the SU collapsed along with the facilities and development for the Energia program. Think that the Energia in the Buran configuration only flew twice.

[Frozen_Heart]

Well first we have to ask what is the SLS meant to do?

 

We could make the assumption that its main purpose is to give jobs to various lobbyists states, in which case it does its job perfectly.

 

However i'm assuming you're asking more for something designed to be able to throw unmanned probes to the far reaches of the solar system, and carry manned payloads as far as Mars? All for a lot cheaper than the SLS.

[ZooNamedGames]

3 minutes ago, Frozen_Heart said:

Well first we have to ask what is the SLS meant to do?

 

We could make the assumption that its main purpose is to give jobs to various lobbyists states, in which case it does its job perfectly.

 

However i'm assuming you're asking more for something designed to be able to throw unmanned probes to the far reaches of the solar system, and carry manned payloads as far as Mars? All for a lot cheaper than the SLS.

We're going with the original purpose of the SLS before nasty politics and everything else started to enter the picture with the goal of this replacement being (as shown in bold in the OP), to launch heavier hardware than what others can provide. Whether they be manned or unmanned is irrelevent. We just want a vehicle we can use.

[Bill Phil]

Hmm...

Skyhook-Venturestar.

That's 5 billion per year, right? If so, then the Skyhook could be built in pieces, using the already existing hook to make subsequent launches cheaper and cheaper. A 1000 km long non-rotating skyhook would reduce the delta-V required by about 1km/s. Even 1km/s would be a huge benefit. Make it even longer, and you'd get more benefits. Now, a skyhook isn't a space elevator, but rather a cable that goes from two separate altitudes. Dangle a cable from some high altitude down to 200km, and then get a launch vehicle (perhaps SLS, it is already developed...?) to do a rendezvous and release its payload. Lowering the Delta-V requirement would enable Single Stage to Skyhook, and lower mass ratios, thus increasing payload mass fractions. Then a vehicle like Venturestar could be practical, and with more payload to boot. More payload per launch, and a set cost per launch, reduces the cost per kg.

And if you want a new vehicle, we could revive Venturestar, or at least something similar to it. SSTS is far easier than SSTO.

Edited May 20, 2017 by Bill Phil

[magnemoe]

3 hours ago, ZooNamedGames said:

Possibly, but reusability limits range. The idea is we're sacrificing reuse for range.

Plus... am I the only one who thinks that Elon's solution to increased payload mass is just a bit too Kerbalish? In that he goes for the asparagus staging route... I mean it works but it is a bit Kerbal.

True, therefor reuse of boosters was for testing, and some an partial replacement for falcon heavy in disposable mode.
Not sure if FH will ever use crossfeed, my 4 and 6 booster idea does not, it used engine shutdown to save fuel in core stage. 

[ZooNamedGames]

23 minutes ago, magnemoe said:

True, therefor reuse of boosters was for testing, and some an partial replacement for falcon heavy in disposable mode.
Not sure if FH will ever use crossfeed, my 4 and 6 booster idea does not, it used engine shutdown to save fuel in core stage. 

Interesting exchange for fuel. It's reasons like this, is why I like to let ideas fall to others since often you think of something I only had considered.

[MajorLeaugeRocketScience]

I've had some concepts going in my head for a while, so here's some:

Artemis Series:

The first stages come in 'blocks'. Block 1 is about 4m diameter, somewhere around 35m long. It should use either a RS-68 derivative or something in that class. Used as 1st stage in Artemis 1, boosters in Artemis 2 Medium. Block 2 is 6-7m diameter, and somewhere around 45m long. It should use 4-5 of the previously mentioned engines. Used as Artemis 2 First stage, Artemis 2 Heavy Boosters, and Artemis 3 Boosters. Block 3 is 10m diameter and 60m long. It will use either 8-10 perviously mentioned engines or 3 much larger engines. This block is used as the Artemis 3 Core Stage. Block 3 is designed to be reusable. 

Second Stages also come in blocks. Block 1 is pretty much just a F9 upper stage using LH2 instead of RP-1 and with an RL-10B-2. It can be used on any launch vehicle. Block 2 upper stage will use 3 new LOX/LH2 engines designed for maximum efficiency. Can be used on Artemis 2 or 3, possibly on top of the Block 3 Upper stage. Block 3 upper stage will use 1-2 J-2X derived engines, made to be more cost effective. 

Here is a recap:

Block 1 First Stage	Block 2 First Stage	Block 3 First Stage	Block 1 Second Stage	Block 2 Second Stage	Block 3 Second Stage
Can be used on Artemis 1, or on 2 Medium	Can be used on Artemis 2 as CCB, or as Artemis 3 Boosters	Used as Artemis 3 Core	Used on any LV	Used on Artemis 2 and 3, can go on top of Block 3 upper stage	Used on Artemis 3
Parachute Recovery	Ocean soft landing	Boost-back return	No recovery	No recovery	Can be used for on orbit transfer, like ACES

 

[wumpus]

7 hours ago, ZooNamedGames said:

Too bad the SU collapsed along with the facilities and development for the Energia program. Think that the Energia in the Buran configuration only flew twice.

About as likely as this:https://en.wikipedia.org/wiki/Saturn_C-3  (or on video) https://www.youtube.com/watch?v=PetUQPu1wTA [vintage space]

Although I've called this the "Apollo Launch System" and would expect it to be as political as the SLS (since the whole idea of both was to reuse/maintain the infrastructure and the jobs involved).  It looks good, but I really don't expect the "Apollo recovery" to really work.

 

[ZooNamedGames]

10 minutes ago, wumpus said:

About as likely as this:https://en.wikipedia.org/wiki/Saturn_C-3  (or on video) https://www.youtube.com/watch?v=PetUQPu1wTA [vintage space]

Although I've called this the "Apollo Launch System" and would expect it to be as political as the SLS (since the whole idea of both was to reuse/maintain the infrastructure and the jobs involved).  It looks good, but I really don't expect the "Apollo recovery" to really work.

 

Yeah by this point Saturn requires a severe engineering and design overhaul for the times as some aspects of it like the Apollo S-IVB computer was massive and significantly outdated.

[YNM]

I presume modularity shall be the centre piece. Take some good existing design and just add moar boosters.

[magnemoe]

9 minutes ago, YNM said:

I presume modularity shall be the centre piece. Take some good existing design and just add moar boosters.

Yes, like the atlas evolution or mine super heavy falcon who is even more modular.

[Norcalplanner]

It seems to me that the major decision point is whether or not the launcher is man-rated.  If we're talking about something like Skylab / Saturn IB, where you have a large payload launched to orbit and the crew coming up separately a few hours later.  Then we don't need to bother man-rating the whole thing and rely on Falcon 9/Dragon or something similar to get the crew up.  

Off the top of my head, it seems like when you want cheap power, designs gravitate to SRBs and Kerolox.  Hydrolox is efficient, but just too expensive, and the current SLS is having problems with the tank.

In my mind, a heavy cheap Kerolox/SRB lifter would be something like an 8-10-meter core made using modern aluminum/lithium alloy (similar to Falcon 9), with 5 to 7 modern deep-throttleable Kerolox engines (TR-107 or similar) with large disposable SRBs (possibly as large as 4 or 5-segments, with 2, 4, or possibly even 6 depending on the payload) and a Kerolox upper stage with 2 or 4 Merlin 1D vacuum engines. 

 

[DDE]

My own idea for am Evolved Energiya includes two stage sizes - 4.1 Baiterek core, rail-transportable, and 8 m Energiya core, air-transportable. The system covers everything from upper-medium to the superheavy class, by using one-to-three 4.1 m or an 8 m with two-to-six 4.1 m strap-ons as the first stage, possibly with propellant crossfeed, and 4.1 or 8 m upper stages. It would of course put the ULA range out of business; no reusability decreases initial costs.

The big idea is using methalox on all stages. First stage engine would be the RD-0141, derived from RS-25E-equivalent RD-0120; four for an 8 m and one per each 4.1 m. Upper stage motors would either be two or four RD-190s (heavily upgraded RD-120s) with telescoping nozzle extenders. Evolved upper stages would use RD-0140s, a new member of the RD-4xx solid-core fission thermal rockets family, or the coveted RD-600 vortex-confined gas-core nuclear thermal motor, but that is way over budget.

The old Energiya pads were rated for Vulkan's eight RD-170 strap-ons, so they should be usable considering they've survived N-1 "launches". Methane/LNG infrastructure is quite affordable.

I don't have any math for it.

Edited May 21, 2017 by DDE

[sevenperforce]

Raptor-derived Falcon X, and devote a bunch of funding to orbital prop transfer. With reliable orbital prop transfer and a single HLV, you can send anything anywhere.

[shynung]

38 minutes ago, sevenperforce said:

Raptor-derived Falcon X

This, with strap-on kerolox boosters that glide back to the launch site.

[sevenperforce]

6 minutes ago, shynung said:

This, with strap-on kerolox boosters that glide back to the launch site.

Glide back or boostback? I think the latter is more fuel efficient.

But yeah, for Falcon X I'm thinking something roughly New Glenn sized, or slightly larger, with ten Raptors. But lithium-aluminum bodies rather than composite, to save cost and permit expendable missions. One nice thing about the Raptor family is being able to use methalox for RCS and optional upper-stage landing thrusters.

I'm a sucker for biconic reentry and dual-thrust-axis landing of the upper stage but that's probably not realizeable.

This whole topic is interesting given that the SLS is derived from a design that our buddies over at NSF originally proposed. 

Edited May 21, 2017 by sevenperforce

[TheEpicSquared]

I'm with @magnemoe I'm this one. FH can already take 63.8 tons to LEO and adding two or four more first stages would easily take the payload capacity above 70 tons.

Another idea would be to literally take a Falcon 9, and add 4 more Falcon 9's to it. Upper stage included. Of course, the center rocket would have to be heavily modified to be able to support four more rockets, but hey, we have 5 billion dollars!  

Maybe the four side stages would burn at liftoff, or the middle as well at a low thrust if needed. Some time into the flight, two of the side cores could throttle down, with the other 2 side cores operating at full thrust until burnout (I'm assuming an expendable configuration here). When the first two side cores separate, the two remaining throttle up to full power, and the middle core ignites and throttles to 50% or so to aid with thrust (if the middle core ignited from liftoff it would just throttle up to 50% or so). 

When the two remaining side cores burn out and are jettisoned, the middle core throttles up to full thrust until burnout and jettison.

At this stage you would have a middle upper stage of an F9, along with four strap-on upper stages. The staging sequence would go similarly to the first stages' staging sequence. 

The four strap-on would ignite first, with two throttling down a bit to conserve propellant. When the 2 strap-ons that were operating at full thrust burn out and separate, the 2 remaining strap-ons throttle up to full and the core ignites to 50% thrust or so. When the final 2 strap-ons burn out and separate, the core second stage throttles up to full thrust and carries the payload to orbit and beyond.

Also, if the core second stage was converted to use a a hydrolox or other high isp propellant, this would mean more payload could be ferried around while in space.

 

^ Now, I have no idea if that's practical in real life (probably not ), but it's an idea.

And, as stated, we have 5 billion dollars, right?  

[shynung]

3 minutes ago, sevenperforce said:

Glide back or boostback? I think the latter is more fuel efficient.

Glide back, so the booster can use every last drop of propellant to push the main stack. The wings and landing gear would be sized for an empty booster, and it would have no parachutes or wheel brakes -  just a tail hook, to stop it Navy-style.