Kerbol Escape using only Boosters

[UmbralRaptor]

I\'m blaming Foamyesque for this one.

My rocket has 135 SRBs, 7 stages, and masses 250.56 tonnes (excluding struts). This is in fact smaller than some late model drag racers.

I launched at dawn, to get a good lineup. No maneuvers were performed.

So, anyone want to work out the smallest SRB-only rocket capable of going into interstellar space? Or if you\'re feeling really insane, sundiving with SRBs?

[jebbe]

So the challenge is to leave Kerbins SOI with SRB\'s?

I did this a while back - it\'s not exactly the smallest possible design, but I was able to return and land safely:

http://kerbalspaceprogram.com/forum/index.php?topic=7055.msg99308#msg99308

[foamyesque]

So the challenge is to leave Kerbins SOI with SRB\'s?

I did this a while back - it\'s not exactly the smallest possible design, but I was able to return and land safely:

http://kerbalspaceprogram.com/forum/index.php?topic=7055.msg99308#msg99308

No, it\'s to leave KerBOL\'s. Leaving Kerbin\'s is easy.

I had to go to.sleep. Curse you, Raptor. =(

[cardgame]

So is this stock parts only?

[foamyesque]

So is this stock parts only?

It is pretty trivial otherwise.

[UmbralRaptor]

It is pretty trivial otherwise.

Yep. substantially better Isp, mass ratios, and burn times available in, say, NovaPunch would likely result in *much* smaller rockets.

[jebbe]

Ok, I made Kerbol escape with 195 boosters, 12 decouplers, 183 struts, 4 winglets and the stock pod. If I didn\'t miscount... Pretty sure there\'s a lot of potential for optimization though.

[UmbralRaptor]

A marginal decent improvement: 117 105 boosters, 6 stages, 1 ASAS, 12 winglets, and a pile of struts. I suspect that gravity drag is a bigger enemy than aerodynamic drag with this design. Maybe if I included a pitchover...?

I\'m going to say that a mechjeb or the like is okay. Also, I\'m unsure if the numbers I\'m getting out of my spreadsheets are reasonable. Is it normal for ?V for lower stages to be lower than for upper stages for a minimum mass design?

Edit: I did better than I thought. <100 boosters should be possible...

Edit 2: Okay, that\'s hilarious. My paper ?V for this is *lower* than for my stock single stage to Kerbol escape.

[jebbe]

Sorry I\'m a little confused: Are you going for Kerbin escape (entering the sun\'s sphere of influence), or Kerbol escape (escaping the sun)? Title and text specify Kerbol escape, but I can\'t really tell from your screenshots where you\'re going. If you escape Kerbol with your craft, wew, then I really need to work on my design...

[UmbralRaptor]

Kerbol escape -- getting on an escape trajectory from the sun. Sorry about the screenshots being unclear, I just wanted to show that it was hyperbolic as of entering Kerbol\'s SOI.

[jebbe]

You got me pretty impressed, but I felt like I had to do better: Taking some inspirations from your design, it still took me quite some time and a lot of attempts, but I finally made it with 104 srbs, 6 decouplers, 97 struts and the pod. No fins, SAS or ASAS. Oh, and I left quite a lot of debris and crews stranded in almost-escape orbits...