[It's finally here!] Apollo Replica "MUNBUG XII" Saturn V, CSM, Lander, Buggy

[Giggleplex777]

You should use the same engine for the S-II and the S-IVB. Also, don't for get the auxiliary propulsion system on the S-IVB!

Edited September 4, 2014 by Giggleplex777

[Mulbin]

You should use the same engine for the S-II and the S-IVB. Also, don't for get the auxiliary propulsion system on the S-IVB!

I know that's how it's done on the real one... but lifting my S2 on five skippers just aint gonna happen

Edited September 4, 2014 by Mulbin

[Mulbin]

A couple more updates, think I'm done for the night!

Hopefully the hour it took to make this perfect circle will be worth it! This ring will hold the interstage between the 2nd and 3rd stages. It works a bit like the half stage on my Atlas.

... and here is the first test flight with the first stage! Plenty of testing and adjusting to do to make sure it has the DV it needs. It certainly looks right... just might not work right yet

[GusTurbo]

Great to see you back on this, Mulbin.

Questions: are those fuel tanks all full? Also, have you tried the Part Angle Display plugin? It allows part rotation at whatever degree increment that you want. It's fantastic.

[Darth Lazarus]

hrmmm ... i want to get my hands on the J-2's cluster ...

[Rune]

Great having you back! I know how it is around babies and don't worry, the fun has just begun But look at the bright side you'll soon get close to 6 hours of sleep a day!

As to Munbug needing an update with the new NASA parts, sure! My Phoebus got one and became much, much closer to the real thing in both form and function... only I kept at it with Skippers as F-1 equivalents (check that out on R-SUV! I built it with all the tricks I learnt from you after all). And right now I have a couple of Phoebus V-25(S)U craft files whose payload's names start with "Duna '69" that you are going to love when I get them finished.

Rune. Amazing how well my engine "translation" (F-1=Skipper, J-2=LVT-45) works when extended to AAP replicas and other stuff with Saturn V derivatives, the big NASA boosters end up just the right size.

[sgt_flyer]

yeh, those tanks contains way too much fuel for a S-V lookalike you should consider emptying those tanks and clipping a few 2.5m tanks for your fuel needs (this way you won't have to worry about the fuel bars being incorrect due to partially fuelled tanks) and you'll be able to use smaller engines

[Mulbin]

I'll have a play around, although initial tests show that the rocket is only just limping into orbit with this setup... don't forget just how many tons of girders I have on the top of this thing

[Majorjim!]

I kept at it with Skippers as F-1 equivalents

I'll have a play around, although initial tests show that the rocket is only just limping into orbit with this setup... don't forget just how many tons of girders I have on the top of this thing

As Mulbin said those ibeam fairings are very heavy so more is required to lift it. And Mulbin, dont even think about scrapping the Ibeam fairings!

[Mulbin]

OK, just completed an orbit insertion and transfer... just enough fuel, only 1.2 units left in the S-IVb tank after transfer! Interstage is working nicely.

Not likely to look at smaller engines as my S-IVB, fairings and modules weighs 102 tons

Total rocket weight on the pad is 1672 tons!

[Majorjim!]

OK, just completed an orbit insertion and transfer... just enough fuel, only 1.2 units left in the S-IVb tank after transfer! Interstage is working nicely.

Not likely to look at smaller engines as my S-IVB, fairings and modules weighs 102 tons

Total rocket weight on the pad is 1672 tons!

wowza thats heavy!

Any updates?

[Mulbin]

Actually, might move even further away from accurate engine scale... after all Munbug is about asthetics. Trying out a config with the big KR-2L engines on the second stage.

Cons:

Oversized for J2s

Pros:

Sufficient lift for second stage without clipping multiple engines.

Engine fairings act as an interstage which is..

a. very pretty

b. weightless

c. has my USK flag on it!

I could put smaller stacked engines on but then I would have to break the rocket up with another ugly interstage made from panels, i think my solution will look better.

[Mulbin]

I think this looks much better than the alternative.

[GusTurbo]

That does look great!

Do the engine bells clip through each other with the KR-2Ls? I tried to use them with my Saturbo V, and found that they were just way too big to integrate nicely. I can't stand when engine bells visibly overlap.

[WooDzor]

Mulbin, i am surprised you need these massive engines at the bottom. Are those H beams really that heavy? To be fair my Saturn V / Apollo rocket only has a TWR of 1.05 at launch, but i could probably squeeze a bit more fuel out of the upper stages, but I never bothered because it worked

[Rune]

Totally different weight classes. I mean, I could tell you that it can also be done on Skippers, but then there's no way you could put your flavor of CM+LM if you did that, right? Well, I could with mine... and I have them thrust-limited to imitate Saturn's low T/W at liftoff. Note the differences in diameters:

But that is good, because the best Munbug is the original Munbug. We'd do best to go after different things that focus on other aspects.

Rune. I also got mine "one or two" parts lighter than Munbug .

Edited September 5, 2014 by Rune

[WooDzor]

Rune. I also got mine "one or two" parts lighter than Munbug .

Mine is similar sized as Mulbins though. His crafts are known to be very tight on fuel, and I wonder whether he'll be able to pull it off with 5 mainsails in the first stage too by limiting the amount of fuel in the upper stages to a bare minimum.

[Majorjim!]

Nope and nope.

Having made a Saturn V with working Ibeam fairings after seeing mulbins original one I can say that skippers will not do it. Not even mainsails on their own will

cut it.

[Mulbin]

That does look great!

Do the engine bells clip through each other with the KR-2Ls? I tried to use them with my Saturbo V, and found that they were just way too big to integrate nicely. I can't stand when engine bells visibly overlap.

Yes... another Con. Also I've found that the engine fairings don't separate very nicely as an interstage so may go back to using mainsails (it will have to be ten mainsails clipped together).

Mine is similar sized as Mulbins though. His crafts are known to be very tight on fuel, and I wonder whether he'll be able to pull it off with 5 mainsails in the first stage too by limiting the amount of fuel in the upper stages to a bare minimum.

No... definitely not with the amount of weight from the I-beams. Just to clarify I'm not using 5 of the large engines on the first stage... I'm using 10! 5 wouldn't get it off the ground so 5 Mainsails?... no chance!

To get a comparison take your first and second stages off and just put your S-IVb, payload and fairings on the pad, then check the weight... mine weighs 102 tons!

Edited September 5, 2014 by Mulbin

[Majorjim!]

the engine fairings don't separate very nicely as an interstage

I was wondering about that. Hmm.. Why not use the structural panels for the 1st/2nd inter-stage ring.

[Giggleplex777]

Mulbin, how heavy are allthose I-beams and payload? Your rocket seems way larger than it needs to be.

Edit: Judging from your picture from a previous post, it's about 60 tonnes. So 100 tonnes to almost LKO and 60 tonnes to TMI. My 100 tonne lifter had 14 orange tanks in the first stage powered by seven mainsails and 7 orange thanks and skippers in the second stage. Your rocket has enough room for more than 20 orange tanks in the first stage and 14 in the second.

Also, what's that third stage interstage ring for? The interstage for the S-IVB stays attached to the S-II.

And this:

Edited September 5, 2014 by Giggleplex777

[GusTurbo]

Sorry to deluge you with questions! What kind of part count reduction have you seen, switching from the numerous 1.25m tanks to the 3.75m tanks?

@Giggleplex: I didn't know about the auxiliary propulsion system -- looks like a good use for the verniers.

Edited September 5, 2014 by GusTurbo

[sgt_flyer]

@Mulbin - you should try to use disabled standard control surfaces as fairings it's a bit difficult to set in place, but it's waaay lighter than beams (though if not used correctly, those can upset a bit the balance)

here's a fast exemple i've thrown around (ok, once you use those you generally need to reinforce the control surfaces on the S-IC, but those weight peanuts compared to beams ) (plus, you can add other radially attachable stuff onto the control surfaces )

@Giggleplex yeh, i toy a lot with this kind of RCS pod for some upper stages i design - you can fully control the attitude of an upper stage + payload with a pair of these. (Reactions wheels are too OP )

Edited September 5, 2014 by sgt_flyer

[Mulbin]

I was wondering about that. Hmm.. Why not use the structural panels for the 1st/2nd inter-stage ring.

http://cloud-4.steampowered.com/ugc/3278927975618688503/083172B7C188FC426B7CB2ED8BBE1FA7B82927F1/

Yep, I think that might be the way to go! It won't look quite a nice on the pad but it will solve a lot of problems!

Mulbin, how heavy are allthose I-beams and payload? Your rocket seems way larger than it needs to be.

Also, what's that third stage interstage ring for? The interstage for the S-IVB stays attached to the S-II.

It looks about the right size for a Saturn V to me... It would look a bit odd if I made it smaller. Thanks for the heads up on the interstage, I based it on pictures that had it attached to the S-IVb, lots of inaccurate images on google!

Nice find on the auxiliary system, I'll add it in!

Sorry to deluge you with questions! What kind of part count reduction have you seen, switching from the numerous 1.25m tanks to the 3.75m tanks?

I think it's around 700 parts now which is a definite improvement. Runs well on my system.

@Mulbin - you should try to use disabled standard control surfaces as fairings it's a bit difficult to set in place, but it's waaay lighter than beams (though if not used correctly, those can upset a bit the balance)

here's a fast exemple i've thrown around (ok, once you use those you generally need to reinforce the control surfaces on the S-IC, but those weight peanuts compared to beams ) (plus, you can add other radially attachable stuff onto the control surfaces )

http://i.imgur.com/p1eXcG2m.png

@Giggleplex yeh, i toy a lot with this kind of RCS pod for some upper stages i design - you can fully control the attitude of an upper stage + payload with a pair of these. (Reactions wheels are too OP )

It's a great weight saver... but I prefer the look of the i-beams, and Munbug is all about the looks!

Doing some more testing now as my latest setup has good TWR but way too much DV!

[Mulbin]

OK, I'm now experimenting with reduced fuel and smaller engines in the second stage with some success.

Out of interest does anyone have the TWR for each stage? Also kerbal equivalent DV for each stage would be useful (not the real DV of saturn V stages... but the equivalent percentage for the kerbal universes lower DV).