[1.2 - 1.4] Real Scale Boosters, 0.16 (2018-03-12)

[Pappystein]

8 hours ago, NecroBones said:

For Delta II & III, originally I was going to scale them independently of Delta IV, but there's some minor part sharing going on, so it's better to keep them in scale to each other. So it's all going with the D4's CBC being 3.75m and the rest of the sizes follow from that. Delta III looks pretty good at this scale:

 

 

Sorry for the absence from the scaling discussion prior to this.  RL commitments can suck.   Stock Scale, assuming independent scaling of the main tanks.  Wouldn't Delta II be a 1.875 tank (2.44m aka 96" real Diameter), Delta III a 2.5m tank (4m Real World) The Delta Cryogenic Second Stage (DCSS) is in it's 4m variant on the Delta III.   The Delta IV can fly either a 4m DCSS or an enlarged 5m DCSS depending on the variant of Delta IV.   Delta IV being a 5m real world Diameter scales nicely to 3.75m Kerbin.  The Delta-K for the Delta II 2nd stage is a completely different beast than the DCSS for the Delta III and Delta IV.  

 

Hope this is helpful.  All the info above is from Wikipedia.  I have detailed scale model drawings of the Delta II with dimensions but unfortunately this is for the model rocket crowd so no internal drawings or diagram of the Delta K.

[NecroBones]

13 minutes ago, Pappystein said:

Sorry for the absence from the scaling discussion prior to this.  RL commitments can suck.   Stock Scale, assuming independent scaling of the main tanks.  Wouldn't Delta II be a 1.875 tank (2.44m aka 96" real Diameter), Delta III a 2.5m tank (4m Real World) The Delta Cryogenic Second Stage (DCSS) is in it's 4m variant on the Delta III.   The Delta IV can fly either a 4m DCSS or an enlarged 5m DCSS depending on the variant of Delta IV.   Delta IV being a 5m real world Diameter scales nicely to 3.75m Kerbin.  The Delta-K for the Delta II 2nd stage is a completely different beast than the DCSS for the Delta III and Delta IV. 

 

Originally I was going to scale them separately, similar to this, but I ran into issues with some of the shared assets. They would either need to be split out to separate parts, or just let them all use the same scaling. Basing it on the DeltaIV CBC going to 3.75m (from 5.1m), that makes the upper portion of the Delta III 2.94m, and the Delta II becomes 1.76m. Those tanks become a little less friendly, but I can make adapters, and also the fairings work great over payloads with standard sizes.

 

If I scale them separately, another twist is that both the Delta II and Delta III are supposed to be the same diameter in the lower tanks. So I could scale them both, either based upon the top of the Delta III, or based on the bottom diameter (the original plan). Or I could scale those separately from each other too, which would look strange and prevent them from sharing the same engines and SRBs at the correct scales. Since the Delta III upper and lower diameters also are not a nice 2:1 ratio, it's going to be non-standard at one end or the other, or else I have to model a new tank.

 

So while these other options aren't off the table, my feeling was that the "path of least resistance" was to keep all of the Deltas in scale to each other, and pick one (the 5m CBC) to scale to a standard size and work from there.

[Pappystein]

3 minutes ago, NecroBones said:

 

Originally I was going to scale them separately, similar to this, but I ran into issues with some of the shared assets. They would either need to be split out to separate parts, or just let them all use the same scaling. Basing it on the DeltaIV CBC going to 3.75m (from 5.1m), that makes the upper portion of the Delta III 2.94m, and the Delta II becomes 1.76m. Those tanks become a little less friendly, but I can make adapters, and also the fairings work great over payloads with standard sizes.

 

If I scale them separately, another twist is that both the Delta II and Delta III are supposed to be the same diameter in the lower tanks. So I could scale them both, either based upon the top of the Delta III, or based on the bottom diameter (the original plan). Or I could scale those separately from each other too, which would look strange and prevent them from sharing the same engines and SRBs at the correct scales. Since the Delta III upper and lower diameters also are not a nice 2:1 ratio, it's going to be non-standard at one end or the other, or else I have to model a new tank.

 

So while these other options aren't off the table, my feeling was that the "path of least resistance" was to keep all of the Deltas in scale to each other, and pick one (the 5m CBC) to scale to a standard size and work from there.

I can understand path of least resistance.  One point however, EVERY document I have on Rockets covering the Delta III are unanimous in Fuselage diameter of 4m.  Maybe the Oxygen tank is standard 2.44 inside but the outer-skin has a 4m diameter.   The Kerosene tank was shortened down and widened to 4m to preserve total rocket height compared to the Delta II.  This reduced changes to the launch facilities as the Delta III was designed for longer payloads.   Considering it was canceled after what, 3 launches?, not that big of a deal.

 

Edited April 20, 2016 by Pappystein
update

[NecroBones]

1 minute ago, Pappystein said:

One point however, EVERY document I have on Rockets covering the Delta III are unanimous in Fuselage diameter of 4m.  Maybe the Oxygen tank is standard 2.44 inside but the outer-skin has a 4m diameter.   The Kerosene tank was shortened down and widened to 4m to preserve total rocket height compared to the Delta II.  This reduced changes to the launch facilities as the Delta III was designed for longer payloads.   Considering it was canceled after what, 3 launches?, not that big of a deal.

 

 

Yes that's right, 4m at the top. The lower portion of the first stage is the same 2.4m diameter as the Delta II. I have the Delta III first stage modeled as a single part, not two with an adapter.

 

[Pappystein]

2 minutes ago, NecroBones said:

 

Yes that's right, 4m at the top. The lower portion of the first stage is the same 2.4m diameter as the Delta II. I have the Delta III first stage modeled as a single part, not two with an adapter.

 

Ach! Sorry My Bad!   I saw the dimensions and never thought that they would do an over under like that (IE I thought the wider section was 100% the payload section and not the 2nd Stage + Payload.

No wonder they had so many problems with the Rocket.   You can clearly tell that they didn't have advanced Aerodynamics predictive computers during the design of this rocket.   At Max-Q that upper tank has to hum with aerodynamically induced vibrations.  The bottom of the 4m Kerosene tank is practically the tail end of a Semi truck....

 

 

[NecroBones]

1 hour ago, Pappystein said:

Ach! Sorry My Bad!   I saw the dimensions and never thought that they would do an over under like that (IE I thought the wider section was 100% the payload section and not the 2nd Stage + Payload.

No wonder they had so many problems with the Rocket.   You can clearly tell that they didn't have advanced Aerodynamics predictive computers during the design of this rocket.   At Max-Q that upper tank has to hum with aerodynamically induced vibrations.  The bottom of the 4m Kerosene tank is practically the tail end of a Semi truck....

 

lol, no worries! Yeah, it's a really strange hybrid. I think it looks cool, but at the same time I can see why they abandoned it as a "transitional" design before just going to the Delta IV.

 

But anyway, yeah, I think at least for the first release we'll just have the Deltas all scaled together like that, so they can mix-and-match parts and have them all line up within that family. If there's enough interest, I could also make a second set at different scales, reusing the art assets, or something. One of the problems I'm facing is that most of these rocket sets only play nice at once end or the other anyway, since they have so many different diameters. The Saturns are particularly problematic this way. The PSLV is all one diameter, so it plays the nicest, and yet since it uses a solid motor for the 3rd stage, it's tricky to get it into the right orbit too. So many trade-offs everywhere.

 

 

[Pappystein]

8 minutes ago, NecroBones said:

. One of the problems I'm facing is that most of these rocket sets only play nice at once end or the other anyway, since they have so many different diameters. The Saturns are particularly problematic this way. The PSLV is all one diameter, so it plays the nicest, and yet since it uses a solid motor for the 3rd stage, it's tricky to get it into the right orbit too. So many trade-offs everywhere.

 

 

In my experience with other mods.  Once you goto a Standard diameter chart (0.625, 1.25, 1.875, 2.5,3.75,5,7.5 etc) you quickly have to re-create many of your transitional pieces.   However, Converting these trasitional pieces to correct scale ends, allows for other uses...  For example, I have many Titan I Launchers I have made using FASA parts.  I re-scaled the 5m to 3.75m Inter-stage to be a 2.5m to 1.875m interestage via a simple create copy and scale mod-manager file.   So initial coversion from REAL dimensions to Kerbin scale is torturous but the assets are easy to re-use later for other uses.

 

Edited April 20, 2016 by Pappystein
Spelling correction

[NecroBones]

5 minutes ago, Pappystein said:

In my experience with other mods.  Once you goto a Standard diameter chart (0.625, 1.25, 1.875, 2.5,3.75,5,7.5 etc) you quickly have to re-create many of your transitional pieces.   However, Converting these trasitional pieces to correct scale ends, allows for other uses...  For example, I have many Titan I Launchers I have made using FASA parts.  I re-scaled the 5m to 3.75m Inter-stage to be a 2.5m to 1.875m interestage via a simple create copy and scale mod-manager file.   So initial coversion from REAL dimensions to Kerbin scale is torturous but the assets are easy to re-use later for other uses.

 

Certainly true. Of course that also creates another trade-off, in that the rockets no longer have the correct internal proportions either. Which bugs the heck out of me. lol

 

[NecroBones]

40 minutes ago, Pappystein said:

In my experience with other mods.  Once you goto a Standard diameter chart (0.625, 1.25, 1.875, 2.5,3.75,5,7.5 etc) you quickly have to re-create many of your transitional pieces.   However, Converting these trasitional pieces to correct scale ends, allows for other uses...  For example, I have many Titan I Launchers I have made using FASA parts.  I re-scaled the 5m to 3.75m Inter-stage to be a 2.5m to 1.875m interestage via a simple create copy and scale mod-manager file.   So initial coversion from REAL dimensions to Kerbin scale is torturous but the assets are easy to re-use later for other uses.

 

33 minutes ago, NecroBones said:

Certainly true. Of course that also creates another trade-off, in that the rockets no longer have the correct internal proportions either. Which bugs the heck out of me. lol

 

This has given me some things to think about though. I think at least some sets of parts can be reworked to fit more nicely into standard sizes. I don't mind the Saturn family being more like a puzzle to put together (though the S-IC and S-II could probably rescale to 5m instead of the 5.7-ish number they are now, due to the 3.75m S-IVB and Instrument Unit).

 

For instance, if I make an alternate model just for the 1st stage of the Delta-III, with the smaller diameter reduced so that it has a 1:2 ratio with the top, then the Delta-III can be 1.25m/2.5m. It would need to have its own copy of the fairing base too, since currently it shares that with the 4m size from the Delta-IV. If the Delta-II is then a 1.25m stack, then both the Delta-II and Delta-III can still share their first stage engine and SRBs meaningfully.

 

Or, the Delta-III's smaller diameter can go upward to make a 3:4 ratio, for 1.875m/2.5m. This would allow for the same as above, but with the Delta-II being 1.875m. Or do a hybrid: Delta-III at 1.25m/2.5m, and Delta-II at 1.875m... but then the SRB and engine sharing between the two wouldn't work so well.

 

I could completely disable the 4m parts from the Delta IV since they won't fit anywhere... or leave them at the 2.94 they're currently scaling to. One option is to disable them for now, and see if there's any interest in reintroducing them.

 

If I work toward making more of it fit the standard sizes, but still not obsess with making all of it fit the standards, it's probably pretty doable with only a small number of new art assets. I'm going to give this some thought, and maybe experiment with the Delta-III as a test case.

[NecroBones]

 

As a point of reference, here are some screenshots with the Jupiter/DIRECT and the Ariane V, with using only stock sizes. The SRBs are proportionately enlarged so that they have 2.5m diameter. The center stacks are larger, Ariane V = 3.75m and DIRECT = 5m.

 

 

[NecroBones]

 

So far I believe this is all going to work. I can push things into some more stock-alike diameters without screwing up the proportions too badly. Some minor things will always be noticeable of course.

I have a test I hacked on a bit last night for the Delta-III, widening the lower portion of the first stage to have a 3:4 ratio with the top, allowing for a 1.875m/2.5m size. For now, I've disabled the 4m parts for the Delt-aIV so that it uses just the 5m parts (at 3.75m scale), and that allowed me to make the shared fairing base/etc scale with the Delta-III only. Since the Delta-III and Delta-IV both use the same upper stage engine, and it scaled with the Delta-IV, I had to stretch the Delta-III interstage by 10% in length to make it fit. Once the Delta-II is ready, it's all set to go in at 1.875m.

I've also rescaled the Castor/Athena/Carrack parts to 1.875m (instead of 1.5m that I was doing). And since the Ares only has a few parts, I managed to get that one done as well. The Ares-I upper stage is scaled to 3.75m and has 75% fuel density by volume compared to stock tanks (works well since it's meant to be a low density cryogenic stage), but the mass ratios are all stock. The SRB is 2.5m, so the interstage only needed a slightly tweaked copy to fit properly, as the SRB is 10% wider by proportion than the Ares would normally have.

Also got a fairing base working for the 500 series Atlas V (whose main stack is 2.5m).

 

[NecroBones]

 

Current rescale factors:

 

    ares      = 0.68181818  // 5.5  -> 3.75
    ariane    = 0.694444    // 5.4  -> 3.75
    arianesrb = 0.819672    // 3.05 -> 2.5
    atlas     = 0.656167979 // 3.81 -> 2.5
    castor    = 0.7944915   // 2.36 -> 1.875
    delta2    = 0.78125     // 2.4  -> 1.875
    delta3    = 0.625       // 4.0  -> 2.5  (and: 3.0(2.4) -> 1.875)
    delta4    = 0.7352941   // 5.1  -> 3.75
    pslv      = 0.892857    // 2.8  -> 2.5
    saturn    = 0.5681818   // 6.6  -> 3.75 (and: 10.1 -> 5.74,  12.2 -> 6.83)
    sts       = 0.595238    // 8.4  -> 5.0
    stssrb    = 0.6738544   // 3.71 -> 2.5

Edit: Note that the Saturn family ends up with non-standard diameters for everything larger than the S-IB and S-IVB sized tanks. Personally I'm OK with that, leaving the Saturns to be a little like putting together jigsaw puzzle (everything fits when assembled correctly). It still lets you use stock scales at the top of the stack, and preserves its iconic look. Everything else I've managed to cram into stock diameters, plus 1.875, which is stock-similar.

 

[VenomousRequiem]

I speak from experience: delta II/III and Castor 30/120 work well at 1.5m. 

[NecroBones]

9 hours ago, VenomousRequiem said:

I speak from experience: delta II/III and Castor 30/120 work well at 1.5m. 

 

Yeah, I was a little torn on that. The thing is, 1.875 is a perfect half-size that a lot of other mods are starting to support.

[VenomousRequiem]

2 minutes ago, NecroBones said:

 

Yeah, I was a little torn on that. The thing is, 1.875 is a perfect half-size that a lot of other mods are starting to support.

Right... With all my time at BDB @CobaltWolf has clouded my judgment on what sizes people accept and what sizes people don't like.

[CobaltWolf]

1 hour ago, NecroBones said:

Yeah, I was a little torn on that. The thing is, 1.875 is a perfect half-size that a lot of other mods are starting to support.

If only more mods supported 1.5m, it would be a standard size...

[Moose Rocket Science]

On 1/25/2016 at 1:53 PM, NecroBones said:

Wishlist / To-Do:

• Several generic radial decouplers and Ullage/Retro SRMs.
• Ariane V - (added in 0.5)
• (maybe) DIRECT-Jupiter (shuttle derivative) - (usable, could use more parts)
• (maybe) Proton (Russian)
• (maybe) SLS, CDR version - (would love to, but multiple mods already have this)
• (maybe) Titan III family
• (maybe) Falcon 9R - (would love to, but multiple mods already have this)
• (maybe) Energia (Soviet)
• (maybe) PSLV/GSLV (Indian) - (PSLV added in 0.6)
• (maybe) Orbital Antares
• (maybe) (new) Mercury/Gemini rockets: Redstone, Atlas D, Titan II
• (maybe) (new) Tsyklon, Cosmos, Vostok (Russian)
• (maybe) (new) Lambda, Diamant, Viking, Vanguard
• (maybe) (new) Long March (Chinese)
• (maybe) (new) H-IIB (Japanese)
• more selections of realistic clamshell fairings

 

Delta 2?

[CobaltWolf]

Just now, Moose Rocket Science said:

Delta 2?

Holy smokes why did you quote the entire OP

[NecroBones]

31 minutes ago, CobaltWolf said:

If only more mods supported 1.5m, it would be a standard size...

True. But 1.875 is pretty widespread comparatively.   EDIT: Lemme think about it a little. I'm still leaning toward 1.875, but until I actually release, it's pretty easy to switch.

 

31 minutes ago, Moose Rocket Science said:

Delta 2?

 

Yep, it's underway. Some of the parts are already in the pack, but it's not complete yet.

 

30 minutes ago, CobaltWolf said:

Holy smokes why did you quote the entire OP

 

Ya, seriously. I trimmed it down.

[NecroBones]

 

You know what, @VenomousRequiem and @CobaltWolf... You just sold me on 1.5m. You know why? Delta III with it's 4m and 2.4m first stage can be scaled to 2.5m and 1.5m. That's very clean. It lets me keep the current 0.625x rescale for that, and get nice clean numbers with a properly proportioned Delta III. The Delta II scales with it at 0.625x as well. Nice.

 

Thanks, to you both!

 

[CobaltWolf]

Just now, NecroBones said:

You know what, @VenomousRequiem and @CobaltWolf... You just sold me on 1.5m. You know why? Delta III with it's 4m and 2.4m first stage can be scaled to 2.5m and 1.5m. That's very clean. It lets me keep the current 0.625x rescale for that, and get nice clean numbers with a properly proportioned Delta III. The Delta II scales with it at 0.625x as well. Nice.

Thanks, to you both!

Hurray!

(It turns out 1.5m is a very useful size for stockalike recreations. It's almost a necessary size if you want real rockets. Gemini and Thor/Delta etc...)

[VenomousRequiem]

3 minutes ago, NecroBones said:

 

You know what, @VenomousRequiem and @CobaltWolf... You just sold me on 1.5m. You know why? Delta III with it's 4m and 2.4m first stage can be scaled to 2.5m and 1.5m. That's very clean. It lets me keep the current 0.625x rescale for that, and get nice clean numbers with a properly proportioned Delta III. The Delta II scales with it at 0.625x as well. Nice.

 

Thanks, to you both!

 

 

1 minute ago, CobaltWolf said:

Hurray!

(It turns out 1.5m is a very useful size for stockalike recreations. It's almost a necessary size if you want real rockets. Gemini and Thor/Delta etc...)

Did we just get credit for being weird? Nice. 

[NecroBones]

Just now, VenomousRequiem said:

 

Did we just get credit for being weird? Nice. 

 

Yep.

[billkerbinsky]

Another component candidate:   The 260" diameter (about 6.6m) aerojet monolithic solid rocket motors.   Never flew, but the smaller configuration was test-fired.

Described here: http://www.astronautix.com/stages/260lidhl.htm and here:  http://www.astronautix.com/engines/aj2602.htm and here: http://www.astronautix.com/engines/aj260x.htm

Use cases: http://www.astronautix.com/lvs/satint05.htm and the monster Saturn V/4-260: http://www.astronautix.com/lvs/satv4260.htm

The V/4-260 would have put additional kerolox tanks on top of the solid boosters, cross-feeding the first stage.

 

[NecroBones]

2 hours ago, billkerbinsky said:

Another component candidate:   The 260" diameter (about 6.6m) aerojet monolithic solid rocket motors.   Never flew, but the smaller configuration was test-fired.

Described here: http://www.astronautix.com/stages/260lidhl.htm and here:  http://www.astronautix.com/engines/aj2602.htm and here: http://www.astronautix.com/engines/aj260x.htm

Use cases: http://www.astronautix.com/lvs/satint05.htm and the monster Saturn V/4-260: http://www.astronautix.com/lvs/satv4260.htm

The V/4-260 would have put additional kerolox tanks on top of the solid boosters, cross-feeding the first stage.

 

Wow that's nuts. I'll have to read up on it some more.