CobaltWolf

[1.8.1][1.7.3] Bluedog Design Bureau - Stockalike Saturn, Apollo, and more! (v1.6.2 "титан" 24/Nov/2019)

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With JNSQ finally coming out for 1.8.1, I've decided to restart my save.

My first crew launch was a baby Mercury

screenshot20.png

It only had the bottom tank and no upper stage so it was an entirely in atmosphere flight, but the experience and science gathered will be invaluable.

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On 2/5/2020 at 9:47 AM, CobaltWolf said:

I just looked, I think we spaced on the descriptions because I don't see anything explaining that the ring has to dock with a fork port and vice versa. :(That'll have to be fixed.

 

More or less textured version of the new small klaw.

UfgTyVh.png

Ah ok that makes a lot of sense haha thanks!

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Trying out an Atlas SM65-A (prototype with no central sustainer) derived launch vehicle. 

I tweakscaled the Jupiter control block to 1.25m so it will act as a spin platform for a small upper stage solid after MECO.

aobmkyxh.jpg

emzTiI7h.jpg

FpZIBNkh.png

MFu280fh.jpg

pTYIfJ9h.png

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On 2/1/2020 at 2:07 PM, CobaltWolf said:

If I remember, we had issues with cost balancing a couple years ago between the Titan and Saturn 1. If you have more feedback, please share - most of the devs don't really have time to play in career a lot to see how it feels.

 

I'll weigh in. In 2.5x I prefer the Delta II 6920 over the Titan 23G because it's got a much better TWR (almost 1.8 vs 1.3 for a 2 ton payload). While they theoretically have the same throw weight, the 23G does it by expending 500 m/s delta V more or so due to a shallower gravity turn (at 2.5x scale). The difference in cost is negligible if you put a probe core on the Titan, the Delta 6920 costs 500 credits more (out of 15k-ish). So I'm not sure you need to do cost balancing as it's six of one, half dozen of another.

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3 hours ago, draqsko said:

 

I'll weigh in. In 2.5x I prefer the Delta II 6920 over the Titan 23G because it's got a much better TWR (almost 1.8 vs 1.3 for a 2 ton payload). While they theoretically have the same throw weight, the 23G does it by expending 500 m/s delta V more or so due to a shallower gravity turn (at 2.5x scale). The difference in cost is negligible if you put a probe core on the Titan, the Delta 6920 costs 500 credits more (out of 15k-ish). So I'm not sure you need to do cost balancing as it's six of one, half dozen of another.

IRL the whole point of the 23G was to not waste the Titan II Silo launched ballistic missiles.   One of the Ballistic missile treaties between the US and the fUSSR allowed the conversion of a certain number of R-36 (SS-9) R-36M (SS-18) and Titan Ballistic missiles into satellite launchers or suborbital payload rockets (aka sounding rockets.)    With a minimum investment, the USAF got a cheap orbital and sub-orbital launcher.   Much like they did with the old Atlas ICBMs that they re-used (Not counting all the Atlases built for sat launch from the start.)   And yes, following STOCK design principles Titan 23G is anemic compared to Delta II.   However if there was a "swords to plowshares"  type mod that had some sort of stock inventory that you purchased earlier on... the 23G would make more sense.   

HOWEVER Some of the 23GS proposals (Agol, Castor IV, GEM46) actually bump the 23G ahead of the low-mid range Delta IIs in lift capacity.    If I recall my tests from 1.7 days in JNSQ, the 23GS with 2 Agols outperformed MOST of the Delta IIs for my launches on a credit for credit basis.   IE I got more Delta-V per credit invested and I could actually launch heavier + physically larger loads.    

In the end it all depends on what your mission is.   I am glad the 23G parts are in the game.   and I use some of them (the ACS system!) often... even on other rockets.  

 

or to Quote Ed Kyle's website:

16.  TITAN 2S

Even as it began launching its first Titan 23G (refurbished ICBM) vehicles on orbital missions from VAFB SLC 4W beginning in 1988, Martin Marietta studied upgrades. The first obvious possibility was to add Delta 2 type Castor 4A or GEM-40 strap-on motors to create a "Titan 2S" (Titan 23S). This approach would have doubled Titan 23G payload, but a new aft skirt would have been needed to support the motors and to protect the first stage engine section. Four to ten SRMs could have been mounted. They would have burned in staggered sequence similar to the Delta 2 solids, though with three burn sets rather than only two.

Given the limited inventory of retired Titan 2 missiles, the cost to develop and fly the upgraded rocket, and the duplication of Delta 2 capability (once Delta 2 began flying from VAFB), "Titan 2S" was never developed. I'm not sure for what specific payload the launch vehicle was considered, but a 2,300 kg to 890 km x 99 deg "reference mission" was mentioned in a 1991 AIAA paper by Bruce French of Martin Marietta.

 

Edited by Pappystein

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Like many others it seems, I too have opted in to trying out this mod for a new JNSQ career game.

Loving the details and modularity of it all! Even if my build menu is crying from obesity - just like with a really good pizza, sacrifices must be made.

That being said, I found friznit's github wiki on building the actual historical rockets with these parts and figured why not start out with building those.

With most of those however, I found that the given build either has far too little delta-v or not enough thrust in certain stages to achieve orbit. In particular, I was having trouble with the Juno I and Jupiter/Juno II rockets: https://github.com/friznit/Unofficial-BDB-Wiki/wiki/Jupiter

Especially the in the Jupiter rocket, the Chryslus 6k & 45k engines have TWR ratios of 0.20-0.30 ish, which is completely inadequate.

Is this intentional or is there something else going on that I am missing?

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1 hour ago, Morphisor said:

Like many others it seems, I too have opted in to trying out this mod for a new JNSQ career game.

Loving the details and modularity of it all! Even if my build menu is crying from obesity - just like with a really good pizza, sacrifices must be made.

That being said, I found friznit's github wiki on building the actual historical rockets with these parts and figured why not start out with building those.

With most of those however, I found that the given build either has far too little delta-v or not enough thrust in certain stages to achieve orbit. In particular, I was having trouble with the Juno I and Jupiter/Juno II rockets: https://github.com/friznit/Unofficial-BDB-Wiki/wiki/Jupiter

Especially the in the Jupiter rocket, the Chryslus 6k & 45k engines have TWR ratios of 0.20-0.30 ish, which is completely inadequate.

Is this intentional or is there something else going on that I am missing?

Are you playing with the official release or with the BDB 1.7 development build? In either case as of the previous release upper stages were switched to 25% of irl thrust scaling same as lower stages. A lot of people use 50% for upper stage engines but for consistency's sake BDB now uses 25% (it also helps resolve issues with engine that have both sea level and vacuum versions).

As such you may find some upper stages have very low twr and require a lofted trajectory just like their real world counter parts. meaning establish a higher initial apoapsis than you normally would. I feel the experience with this kind of scaling is quite nice once you adjust your launch trajectories in JNSQ or similar larger scale systems. However if you dont like it there is a patch in the BDB_Extras that changes engines back to 50% scaling.

I not aware of insufficient Dv on any vehicles. However it should be noted that the current development branch of BDB is revamping all of the early rockets (Vanguard, Redstone, Thor/Delta, Jupiter/JunoII&4. They will be capable of performing the missions they were designed for with all of the early game probes also being revamped or added. Oh and most of the balance testing is being done in JNSQ :)

 

Edited by Zorg

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@Morphisor I was actually literally just flying a Juno IV-A mission with a JPL 6K upper stage. Its the new one in development, I dont recall if there have been significant changes in tank sizes, I dont think so. In any case the overall trajectory for a launch should be similar. 

This was flown with mechjeb using the PVG ascent guidance mode. Doing a few launches with PVG can be a useful learning tool to see how it handles low TWR upper stages while doing a single burn to orbit. The chart below is Altitude vs distance downrange. As you can see it established an initial apoapsis of 120km in order to reach the target altitude of 100km. A lot of IRL rocket launches have this kind of profile for instance the Centaur on Atlas V.

RBr3tQzh.png

If you're not familiar with PVG I have a WIP guide on Friznits wiki (which i really need to update with charts and stuff :| )

https://github.com/friznit/Unofficial-BDB-Wiki/wiki/Launching-and-Trajectories

Couple of bonus images while im here

ZZYVv5lh.jpg

YdEf8fuh.png

s0QBN2Ph.png

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Last time I tried, the "old" Juno IV couldn't even lift itself to orbit in JNSQ.  The revamped one is fine, though it needs a lofted trajectory.  There are some WIP build guides for the new stuff in development in the Issues tab,.  Feedback or suggestions are welcome if anything is not completely clear!

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@Zorg Thanks for the very extensive reply and your hard work on this! And sorry, I did forget to mention the version: I am using the latest official build (1.6.2 with hotfix).

I just went back to my Vanguard craft and noticed the Viklun-50 engine got a significant boost after researching the 3rd rocket node (general rocketry). Can't go back to the un-upgraded version to compare sadly, but now the craft comes in at 5.100 Delta-v before the Staara-II stage - it was definitely lower before the upgrade and needed the Staara booster to make it into orbit.

As for the Juno II which I am now fiddling with:

https://imgur.com/a/DXbxfXb

Note the readouts from KER, particularly Stages 5 & 6 have low TWR even in vacuum. I guess I could try how that works out with some testing - I have already resorted to using the excellent Gravityturn mod to help me get along with both the new scale and the increased variation in launch vehicles. Maybe it can reproduce a similar trajectory as you suggested, with a little help.

Oh and the Chryslus 3DS Polaris first stage starts at 0.93 TWR at ground level with this configuration, so that's a thing.

 

@Friznit Thank you for maintaining those build guides! Really insightful and fun to reproduce.

For the Juno II rocket I mentioned, the guide had only one issue for me: it shows a fairing and this is much needed, but I couldn't reproduce it quite as easily as I thought it would be. I resorted to using a Viklun 0.625 decoupler below the Vicenza stacks, immediately followed up by a Fenris 4688 fairing - interesting the Viklun-4688 fairing seemed more suitable to me - a nicely sloped and right-sized fairing for the job - however as I tried to apply that one, it only works upside down...?:huh: Which leaves it facing the wider side up.

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27 minutes ago, Morphisor said:

interesting the Viklun-4688 fairing seemed more suitable to me - a nicely sloped and right-sized fairing for the job - however as I tried to apply that one, it only works upside down...?:huh: Which leaves it facing the wider side up.

Correct me if I'm wrong, but I think that fairing is intended for the old Able/Ablestar parts.

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10 minutes ago, sslaptnhablhat said:

Correct me if I'm wrong, but I think that fairing is intended for the old Able/Ablestar parts.

May be, however I couldn't find any other that really fit the size and location that suits Juno II upper stage.

 

I just tried about a dozen launches with the Juno II rocket as shown in my screenshot shared earlier. None of them managed to even reach space.

Several problems are compounding here: the first stage's lack of sufficient TWR means it wastes a third of its fuel before gaining proper acceleration and going up. By the time it's expended and the Chryslus-45k needs to take over, it's anywhere between 12k and 16k meters high, depending on trajectory. At that point the 2nd stage still only has 0.6 TWR at most and predictably fails to go anywhere.

Gravityturn basically has no idea how to deal with either, the results being this:

https://imgur.com/jXn4zS3

Or in the best case scenario (with a little help):

https://imgur.com/sjNlDtO

 

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1 minute ago, Morphisor said:

May be, however I couldn't find any other that really fit the size and location that suits Juno II upper stage.

 

I just tried about a dozen launches with the Juno II rocket as shown in my screenshot shared earlier. None of them managed to even reach space.

Several problems are compounding here: the first stage's lack of sufficient TWR means it wastes a third of its fuel before gaining proper acceleration and going up. By the time it's expended and the Chryslus-45k needs to take over, it's anywhere between 12k and 16k meters high, depending on trajectory. At that point the 2nd stage still only has 0.6 TWR at most and predictably fails to go anywhere.

Gravityturn basically has no idea how to deal with either, the results being this:

https://imgur.com/jXn4zS3

Or in the best case scenario (with a little help):

https://imgur.com/sjNlDtO

 

Well, like Pappy mentioned, those are the old and soon-to-be depreciated Juno/Jupiter parts, so I'd guess there's probably some issues with them, though I'm personally not familiar with the LV family and never used those parts in-game, so I might be wrong. You can download the latest version of the development branch for completely revamped Juno/Jupiter parts (still WIP) which fly pretty good, I can get to JNSQ orbit easily with them.

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53 minutes ago, Morphisor said:

Several problems are compounding here: the first stage's lack of sufficient TWR means it wastes a third of its fuel before gaining proper acceleration and going up. By the time it's expended and the Chryslus-45k needs to take over, it's anywhere between 12k and 16k meters high, depending on trajectory. At that point the 2nd stage still only has 0.6 TWR at most and predictably fails to go anywhere.

So the 3 stage vehicle you have there is a Juno IV-B. Ed Kyle's Spacelaunch report is one of our more trusted sources for information and it seems the Juno IV concept was in fact not capable of launching with a full propellant load on all 3 stages. If you run full on the upper stages, you reduce on the lower and vice versa. Friznit will update the wiki with a note on that. The new Juno IV in development with all 3 tanks full can get off the pad barely but with an LR79-NA13 instead of the S3D (in the new update the S3D, Lr79, RS27 and various configs will be a single part with upgradable and switcheable configs). Still adjusted propellant loads will be the optimal way to build it. or strap some castors to it.

"A three-stage Juno IV would weigh up to 62.41 tonnes (137,600 lbs) at liftoff.  Its Jupiter first stage would be loaded with up to 44.5 tonnes (98,100 lbs) of propellant.  The second stage would carry up to 11.14 tonnes (24,550 lbs) of propellant.  The third stage would be loaded with up to 3.4 tonnes (7,500 lbs) of propellant.  Propellant loading would vary depending on the mission type, with maximum upper stage loading for LEO missions and reduced loading for lunar or escape missions.  Reduced upper stage propellant loads would be offset by increased first stage propellant loads, and vice-versa."

http://www.spacelaunchreport.com/jupiter7.html

Edited by Zorg

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16 hours ago, Pappystein said:

IRL the whole point of the 23G was to not waste the Titan II Silo launched ballistic missiles.   One of the Ballistic missile treaties between the US and the fUSSR allowed the conversion of a certain number of R-36 (SS-9) R-36M (SS-18) and Titan Ballistic missiles into satellite launchers or suborbital payload rockets (aka sounding rockets.)    With a minimum investment, the USAF got a cheap orbital and sub-orbital launcher.   Much like they did with the old Atlas ICBMs that they re-used (Not counting all the Atlases built for sat launch from the start.)   And yes, following STOCK design principles Titan 23G is anemic compared to Delta II.   However if there was a "swords to plowshares"  type mod that had some sort of stock inventory that you purchased earlier on... the 23G would make more sense.   

HOWEVER Some of the 23GS proposals (Agol, Castor IV, GEM46) actually bump the 23G ahead of the low-mid range Delta IIs in lift capacity.    If I recall my tests from 1.7 days in JNSQ, the 23GS with 2 Agols outperformed MOST of the Delta IIs for my launches on a credit for credit basis.   IE I got more Delta-V per credit invested and I could actually launch heavier + physically larger loads.    

In the end it all depends on what your mission is.   I am glad the 23G parts are in the game.   and I use some of them (the ACS system!) often... even on other rockets.  

 

or to Quote Ed Kyle's website:

16.  TITAN 2S

Even as it began launching its first Titan 23G (refurbished ICBM) vehicles on orbital missions from VAFB SLC 4W beginning in 1988, Martin Marietta studied upgrades. The first obvious possibility was to add Delta 2 type Castor 4A or GEM-40 strap-on motors to create a "Titan 2S" (Titan 23S). This approach would have doubled Titan 23G payload, but a new aft skirt would have been needed to support the motors and to protect the first stage engine section. Four to ten SRMs could have been mounted. They would have burned in staggered sequence similar to the Delta 2 solids, though with three burn sets rather than only two.

Given the limited inventory of retired Titan 2 missiles, the cost to develop and fly the upgraded rocket, and the duplication of Delta 2 capability (once Delta 2 began flying from VAFB), "Titan 2S" was never developed. I'm not sure for what specific payload the launch vehicle was considered, but a 2,300 kg to 890 km x 99 deg "reference mission" was mentioned in a 1991 AIAA paper by Bruce French of Martin Marietta.

 

My point was they didn't really need cost balancing. You can squeeze more out of the Titan because you can add strap ons while the Delta II is already somewhat maxed in performance. But for comparing builds of the two families with the same throw weight, they come in somewhat equal even if they achieve it in different ways. I think what people tend to favor depends more on their personal piloting preferences and what they are trying to do with it rather than any meaningful advantage of using one rocket over another.

I think another thing too that the mods I use tend to make me favor Delta over Titan for those under 4 ton launches to LKO, part failure mod and part unlock costs. Delta is a nice rocket because it's incrementally upgraded, while the Titan is one big chunk of research and credits to make sure nothing explodes. By the time you get to the Delta II, you've worked out all the teething issues working up through Thor-Able, Thor-Delta, Delta, and Delta I. You save the Titan for manned missions because that's the only thing that gives a decent return for that massive upfront investment required to lower the risk of failure. And even after you develop the Titan II, you still use Delta because it's more reliable and really Titan II is just a stepping stone to Titan III and IV. You are really aiming for that 20 ton capacity when you start developing the Titan II. That's where the lack of part failures sort of hurts Delta in the stock game.

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7 hours ago, Friznit said:

UjPJCsR.png

Which adapter-part is this below the Belle-Interstage?

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Still have to remake (or rebuild, actually) the integrated service pole (as I call it), but the new Redstone Launch Stand I made, designed for the remade BDB Redstone. The hold-down bolts line up exactly with the mounting points on the bottom of the fins, and there are also optional hold-down bolts for standard 1.25m and 1.5m tanks.

Svhk6n7.png

qlM8Dsr.png

 

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8 hours ago, Cheesecake said:

Which adapter-part is this below the Belle-Interstage?

Medium 1.25m to 0.9375m Structural Adapter.  It was inadvertently missing in the dev branch a couple of days ago but Zorg fixed that yesterday.

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22 minutes ago, Friznit said:

Medium 1.25m to 0.9375m Structural Adapter.  It was inadvertently missing in the dev branch a couple of days ago but Zorg fixed that yesterday.

Thank you. Downloaded the newest dev branch now.

And another question: is there a 8096 variant of the Belle-Engine? I only found the 8096-C with bigger bell (too big for Agena D).

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7 minutes ago, Cheesecake said:

Thank you. Downloaded the newest dev branch now.

And another question: is there a 8096 variant of the Belle-Engine? I only found the 8096-C with bigger bell (too big for Agena D).

All engine variants are now on the same part and are selectable using B9 Part Switch, so you want to look for the Belle-RLX81 Liquid Fuel Engine Series part (use the "mafuni" search tag) and then select Belle-RLX81-8096 "Mafuni" variant for Agena-D

Edited by Friznit

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7 minutes ago, Friznit said:

All engine variants are now on the same part and are selectable using B9 Part Switch, so you want to look for the Belle-RLX81 Liquid Fuel Engine Series part (use the "mafuni" search tag) and then select Belle-RLX81-8096 "Mafuni" variant for Agena-D

Checked the newest Dev-branch (https://github.com/CobaltWolf/Bluedog-Design-Bureau/tree/v1.7.0-Development) and the adapter isn`t there. Also there is only the 8048 and 8081. No 8096. B9 is the newest version.

sRo5Rdo.png

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