SLS/Falcon 9 concept design

[BringBackSuperHeavies!]

An SLS concept where the Solid Rocket Boosters are replaced by Falcon 9 first stages attached to the external tank in a circle. That’s the only difference.
Given the difficulty of making those Falcon 9 stages they should be made reusable like in the actual Falcon9 rocket. I got the idea from reading an article stating that if the SRBs were replaced by Falcon Heavy rockets, there would be 50 percent more thrust.

[spacenut]

Design is ok and would work, but why.  Starship/Superheavy will do more payload to orbit and be fully reusable in a single stick. 

The problem with the SLS is two things I see.  One is the core is huge for hydrogen storage which is the most inefficient first stage fuel of all.  Second is the solids.  They are heavy but have a lot of thrust for a short period of time with is limiting. 

The transport crawler would have to be changed also, which is expensive.

Something that has already been discussed is a 5.5 m diameter kerolox rocket that would directly replace the two solids.  One idea was using two upgraded F-1 engines on each booster.  The F-1's were used on the Saturn V booster.  In expendable mode it would allow the SLS to get 150 tons to orbit.  NASA threw this out as too expensive. 

About 15 years ago, another idea was using the Atlas V rocket by strapping several around the core.  This is similar to your idea.  It too was thrown out. 

It is not going to happen, billions more dollars needed, SpaceX isn't interested, neither is NASA, Congress isn't interested (where the money comes from).  So, the best alternative is Starship/Superheavy right now. 

Using a core with strap on solids is old school from the 1970's.  Shuttle was a compromise.  Back then there were several suggestions for building a large flyback booster to carry the Shuttle to orbit.  Never happened due to cost. 

Simple two stage reusable rockets are what is coming in the future.  New Glenn from Blue Origin, Neutron from Rocketlab, and so on.  At least first stages will be reusable.  Musk said Falcon Heavy was hard and expensive to develop.  The center booster has to be reinforced to handle the side loads.  Single stick stacking is easier and more efficient. 

[TrevorMonty]

Simple two stage reusable rockets are what is coming in the future.  New Glenn from Blue Origin, Neutron from Rocketlab, and so on.

Two stage LVs can't deliver large payloads BLEO on single launch which is why NASA developed large 2.5 stage SLS. In orbit refuel allows any LV to deliver its payload to LLO and beyond. Powers that be killed inorbit refueling idea in favor of jobs in my state SHLV.

[BringBackSuperHeavies!]

But back then Congress didn’t realise that the current idea is probably more expensive than the proposals you mentioned. Now that they know this, they would want to make a cheaper , more powerful if possible, alternative. My design would probably be cheaper than the SLS. Even if development costs are higher the launch costs might be lower owing to the at least partial reusability, outweighing the development costs. You say billions MORE dollars, this appears to suggest more spending on top of the spending on the existing SLS. If that’s not what you meant, then clarify. Also, I think this design could exceed Starship/Super Heavy in terms of Payload Capacity (did you do the maths?). And I think the core stage could be made reusable if anyone was willing. If they aren’t interested in the concept, that’s off a completely wrong basis. If SpaceX heard of it, then they might be interested. Also, why would it be necessary to get a new crawler?

I’m sure if this idea were more widely spread, there would be some supporters.

[edzieba]

But back then Congress didn’t realise that the current idea is probably more expensive than the proposals you mentioned. Now that they know this, they would want to make a cheaper , more powerful if possible, alternative.

There were cheaper more powerful alternatives proposed when SLS was being formulated after the cancelation of Constellation (not only but including a SpaceX manufactured single-core all-kerolox version resembling the old Falcon XX concept).
Throw weight and cost were not metrics Congress were using for selection of SLS. Whether it kept the same industries in the same physical locations funded as were active for Constellation and STS was the primary metric. Any replacement would need to satisfy that, regardless of what the rocket (or whatever other project were proposed) would look like or be capable of.