Pappystein

When D-2, and many other proposals were being developed, Centaur had not flown yet. It was BELIEVED that the tank Pressure vessel would be strong enough to complete the boiloff cycle (Gas transfers back to liquid state due to the pressure gradient.) Embitterment due to cold of the then available metals was not considered... Adequately. Same can be said for the ability to retain pressure in a Vacuum (this is honestly the biggest part of the problem.) The Amount of pressure a tank can hold inside of it is ACTIVELY ASSISTED by the outside air-pressure... Air-pressure = 0 ATM, then you have a lower INTERNAL maximum pressure vs when the Air-pressure is 1ATM or whatever. I am dramatically oversimplifying it here but you can get the idea. Mostly D-2 was not picked because it wasn't a 3 man Conic capsule. The Hydrolox issue not being relevant to the decision until after Centaur first flight.

It works in stock but it uses LFO instead of LH2O for fuel. I wrote a patch for it (it is posted on like page 3 of the alternate apollo thread) but it is out of date and did not use either Cyotanks or BDB tanks correctly... and thus is not a great patch. If someone makes a patch for LH2O better than that please post it to the AlternateApollo forum.

Tanks in BDB have an inherent set insulation value. This is in the part configs. I have not played around with it and I don't know the effect of changing it... although I am tempted to use a MM copy to make Centaur C.... the Monocoque tanks would be heavier and moar insulation so.....

So, since the latest round of insanity "we want Saturn C-8" (which isn't a thing) I decided to deep dive the NTRS archive and I found somethings. In 1959-1960 the plan to go to the moon was Earth Orbit Rendezvous utilizing multiple Saturn (that is what we know as the C-1 S-I stage) with whatever upper stages they could fit on it to build a spaceship to go to the moon. It is here that the first problem with Saturn starts. You see the S-I stage we all know and love as Cluster's Last Stand WAS the Saturn Rocket at this juncture. Anything on top of it was SOMETHING ELSE, aka a PAYLOAD for Saturn. The Letter codes (A, B, C, and D) were utilized to study different "Payload stages" combinations to get X, Y or Z pounds of payload into LEO. the Saturn with A upper stages was the Ballistic missile derived (primarily) and included potentially a Baby Cluster above the I stage. the Saturn with B Upper Stages was 220" Diameter new built stages. Something that would lay the ground work for the C series next: the Saturn with C Upper stages was either 220", 240" or 260" in diameter (it changed several times) and was what was settled on based on the conceptual math of the A and B Saturn upper stage plans. the Saturn with C Upper stages of increased diameter (C-3) was not conceived at the point of this document, but C-3 was an outgrowth of the limitations the C-2 rocket had as pointed out in this document. the Saturn D upper stages would combine the C Upper stages with Nuclear propulsion. So at this juncture it isn't C-2N and C-3N but rather D-2 and D-3 for example. About this time NTRS article 19730064135 was penned. In it, a comparison of the then understood paths to the moon before 1970. Assembled Rocket in orbit based on Saturn + B or Saturn + C upper stages (choices had not been done at this time) Much more costly Direct Ascent Rocket based on the concepts of Saturn and Nova but actually NEITHER ONE. Direct Transfer Earth-Moon Rocket (what many of you call C-8) was not part of Saturn and was a "prove this won't work" conceptual math exercise. The Cost and Risk to assemble a Moon lander and return vehicle in space being lower than the cost and risk of a giant Direct Ascent rocket. Direct Ascent Rocket, died before Earth Orbital Rendezvous died. The above is a direct quote from the Article. Direct Ascent CAN NOT be used before the 1970s as it clearly states here. Remember at this time the only part of the rocket called Saturn is what we call the S-I Cluster stage today! Then Kennedy's speech and latter assassination would cancel EOR. EOR could not make the timeline of BEFORE 1970. Long live Lunar Orbital Rendezvous! Long live the Saturn C-5! Also NTRS article 19640058212 has some interesting "Buck Rogers" payloads for the future Saturn Rocket. Many of them were repeated in the 1973 archived document above as well. NOW here is where it gets fun and the waters get muddy. The MSFC version of Direct Transfer Earth-Moon AKA Direct Ascent Rocket was dusted off and polished up to look vaguely Saturn like for the SECOND Nova Program of 1963-1965. It however was NEVER SUBMITTED. Nova grew to obscene sizes and MSFC refocused on Saturn MLV in lieu of NOVA. As it is, and as called out in NTRS article 19660012934, most of the competing Nova Rockets were between 60ft and 80 ft in diameter. My favorite example essentially clusters 6 Saturn V first stages around a 7th central Saturn V first stage Like I said, Nova is crazy stupid, and that includes the baby MSFC one you all keep bemoaning.

So I created a pretty comprehensive QOL list. I am only posting the Saturn portion of the list right now. But I also have Agena and Titan parts that could use QOL adjustments. Some of these are new parts, some are changes to existing parts and the bulk of the work (even though it is only like 3 entries) is alternative paint. Some additional Notes: The S-V stage is not a direct copy paste Centaur. Rather the tank is a thicker walled Centaur that did not eject it's insulation upon reaching space. It kept it until S-V stage ignition. The tank was self supporting so Monocoque instead of Balloon (meaning it is heavier than Centaur D.1) and because of the higher pressure limits has a better boiloff profile. LR119 was never actually built, for sake of convenience and time it was quicker to re-design the 220" S-IV 4 engine stage to the 240" S-IV 6 engine stage we all know and love today RL10B-3, the S-I Engine plate changes and the Centaur C/E should all be B9PS changes with additional variants added to their respective parts.... Although it would be neat if the RL10B-3 was a re-use of the RL10A-3 model with a new texture (different colors) to represent some exotic new material... like Coloumbium? The Centaur one being the one that would require more work than the others. The Auto Jettison for the Insulation would have to either be disabled or re-worked for the Centaur C/E and a somewhat different level of insulation would need to be applied to simulate the improved boiloff characteristics of the higher pressure level capable Centaur tank. ****EDITED**** Centaur C is the Saturn Centaur up until NASA took over management of the Centaur program from Convair. AFTER NASA took over the Centaur designation system was altered and what was Centaur C became Centaur E. And when Lockheed Martin took over the Centaur systems back from NASA they changed the nomenclature again. The existing Centaur V should actually be D.5A per last NASA nomenclature for example

There are some old documents that do reference the C-8... But they are all well past the Saturn V Preliminary design. Prior to the LOR being chosen they were ABMA's NOVA concept with 8 F-1 engines in the first stage. One of MANY MANY MANY NOVA rockets. NOVA deserves it's own mod. It is not a Saturn derivative and honestly MOST of the NOVA rockets were impossible to build then and are still impossible to build today! It is the same reason NASA still likes segmented SRMs... Monolithic SRMs are just too hard to move arround at the cape (let alone GET to the cape!) I really REEAALLYY need to create a document and post it on my Github that states, NOVA deserves it's own mod. It is NOT in any way related to Saturn with the exception that SOME of the NOVA rockets were meant to interface with the Apollo lunar payload for stupid reasons. QUAD AJ-260s on a MLV Saturn WAS an actual proposal But it is as cursed as the fictional C-8 *see above*

This wouldn't be a bad idea for ANY of the BDB crewed capsules.

Boiloff is magic like on the best of days. Build a strong enough tank and you can prevent boiloff from causing losses in propellant volume. Provided you have a small enough volume for the gas to expand into. Because if you apply enough pressure to a Gas, you FORCE it to become a liquid. Now Centaur can't handle those pressures with it's balloon tanks but S-IVB SHOULD ***that is to say this is a guess on my part*** be able to. After all they were looking to use SLUSH hydrogen (a semi solid Hydrogen) for the S-IVC. There is a perfect point for every tank. Sometimes that point is at 0% however (IE the tank never reaches Equalibrium between Liquid and gas conversions.) But most tanks have a point of lowest losses I guess you could say. I feel, given the documents on the Venus and Mars flybys using trains of S-IVC stages, that the S-IVB/C has such a point and it is significant enough to preserve a % of LH2 in space. That all being said, There is no real standard that NASA or anyone else holds people too for boiloff. This means there is no consistent nomenclature/reporting for how long something takes to boiloff. Rather NASA sets the standard by saying we need x% remaining propellant after Y mission parameters. This means that we don't know the actual storage capability of a particular Tank beyond it's stated mission parameters. So since I feel the numbers in BDB Boiloff are too aggressive (based on Centaur D.1 stage flight profiles and out of normal performance of some of those stages) I turn the BDB Boiloff function down to 25% (instead of the Default 50%) This solves the above conundrum for me. Except the whole S-IVB had "Perfect Balsa" Insulation and the Equalibrium point. The point of all of this? We don't have a prefect boiloff system. HECK it doesn't even cover LOX Boiloff etc... But we have one, and with some self tweaking via the effectiveness slider we can fix SOME of the boiloff issues we face. I don't think KSP can handle a Real world Gas-Liquid-gas cycle like real boiloff deals with. So we have what we have. Pull request for deletion of My H-2 patch in-coming. Also I need to change the J-2T-400K from a separate part to a B9PS as I have found evidence that it wasn't significantly larger than the standard J-2T-250K engine.

H-2 is essentially a H-1 Rocket engine with a modified Combustion chamber and new turbopumps and bell that crank the thrust to the 250,000lbf thrust range. Was discontinued as the XIV turbopump (Going from memory and that is also my favorite mark of the Spitfire so I might be wrong there) was of limited reliability INITIALLY and would require about 2 years to make man rated. IE canceled by NASA because Moon Race was all that was important. But the RS-X (which seems to be J-2 sized) would be an awesome addition to the stable of BDB engines

If you are referring to the "white" areas above the bells in the engine bay those are all part of the Flame deflector system (the big plate between the engines on the S-II stage.) It is possible that there are temporary structures to maintain J-2 alignment in there as well. Things that would be removed just before S-II and S-IC stage integration. J-2s never had any Asbestos ablative insulation like the F-1s did. the White color you are seeing is likely due to this either A) being an early S-II, before they started leaving them zinc Chromate green only. or a trick of lighting because of the higher reflective index of the paint coating vs the surrounding (like all the "shadow" pictures from the moon that drive the conspiracy idiots nutz and thinking we faked the moon landing. Yeah, the HG3 files in extra are in fact creations I made and posted years ago... They should be removed from the Final Apollo release (IIRC they have already been removed from the EXTRAS branch along with my MLV and INT Tank extension patchs.) *opens github to check* Yes the only patches left are the J-2T-400K patch and the H-2 engine patch (that also may be depreceiated shortly depending on what Cobalt has or will decide on the subject of BDB native H-2 engine)

SO just a small post here today on the History of Saturn. Friday I received the long awaited Saturn C-2 Preliminary design document from MSFC. This document is now restored to NTRS server but only findable by searching subject "Saturn" and a Date range of 1959-1961 A few things historically here. 1) for the longest time it was believed that the Saturn C-2 used the same Juno V stage as Saturn C-1. Turns out it SORTA does. it is infact 65" shorter and intended to run between 600,000 and 650,000lbs of fuel and oxidizer. The fuel load is mission dependent. 2) the document, dated early 1960 has already replaced the S-III stage with the 4 engine S-II stage. This is contradictory to previous documents we have access to. but most of those were "2nd tier" documents. However interestingly at the time of this document's creation the S-III stage is listed as the 3rd stage for C-3! 3) we finally know Pratt and Whitney's designation for their un-built (well at-least un-flown) LR-119 meant for the S-IV and S-V stages. RL10B-3 (YES that is correct!) It appears that back in the 1960s P&W used the letter after the engine name to denote cycle. So the LR-119/RL10B-3 is a LR-115/RL-10A-3 with a different or at-least altered combustion cycle. We have already seen this in the amzing RL20 that Zorg has integrated into BDB. 4) S-V is NOT even a near copy of the Atlas Centaur but rather an Evolved Centaur. The Tank skin is thicker, has significantly more HTP peroxide and does not shed it's Insulation until RL10 ignition. I could not find how much thicker the S-V's tank skin was but it could be self supporting or a true monocoque structure that relies on no external forces (in this case internal air pressure) At the time this document was drawn up the S-V was still called Centaur C. This would change only once Lewis took control of Centaur away from Convair about a year and a half later. 5) one of the Moon plans just using C-2 rockets envisioned a C-2 with the S-II, S-IV stages surrounded by large drop tanks (similar to the AGENA SOT tanks) These tanks were the length of the S-IV and S-II stages combined and the entire rocket would take approximately 33 launches to assemble and refuel in orbit! But would have a payload capacity similar to Saturn V (10 ton return payload) 6) S-IV was to have insulation that was detachable as well at this juncture! For those interested in reading this. https://ntrs.nasa.gov/api/citations/19630045066/downloads/Saturn C-2 Phase I Preliminary Design Report_CLEAN.pdf?attachment=true

Because like space shuttle, It wasn't re-usable as landed. It would have to go through a whole "re-manufacture" process. Something not really understood until Shuttle was about to fly 20 years latter. Also The X-20 was actually too small to perform any of it's various missions well... When satellites were the size of a Basketball it was plenty big... by the point the X-20 would have flown it would have had to be at least 4x the size to perform the assigned missions. Mind you that is more opinion than "fact"

While I am not the biggest fan of it, you can see the lineage of this in the old FASA Winged Gemini... I much prefer the flexible wing concept, even though it was flawed with the technology at had back in the 1960s rush to the moon. I know there is a paraglider attachment for the BDB Gemini available in a separate mod, but I don't think it has been kept up to date and does not work well in 1.12.... But going by memory there. This won't happen but I would have loved if the bottom (side opposite the ingress doors) of both Gemini and the Big-G modules were removable and could have plug in wheels/skids or science pallets. As I understand it that was a lot of work on the textures for limited gain for many players. X-20 was as flawed or more so than even Space Shuttle... if X-20 had flown even once... Space Shuttle likely would not have flown. However it is a very neat "what iff" concept and allows you to alt/history deep think.

So with @EStreetRockets new SSME engines in Beta Test and available via github on his Dev branch... I thought I would combine dev Branches... Behold the Saturn II LCH4/LH2 based on the INT-19 (Agols subbed for the M55) Yes took advantage of the Milkstool for the Saturn V tower. In short it was a fun flight.... until my wrist guard popped up and hit the space bar... I didn't get to land on the Mun (a second rocket would have had to retrieve them this was a one way mission to the Mun!) Thanks to the BDB team, @AlphaMensae and EstreetRockets for making this launch a fun success... even if my wrist guard broke the flight!

Thank you for keeping space Clean... Course it would have been better if we could recycle that old station after the fact

I think the lot of them also wanted to FLY the X-38 themselves "No computer is better than ****ME****" mentality.

Yes, the X-38 the crew is almost supine. This was chosen because it offered the best g force reductions in ALL flight modes. Remember the final landing was to be by Paraglider. If the entire spinal column is supported evenly there is less likely to have damage to the body in the event of a hard parachute landing. During the actual atmosphere interface to slowdown to subsonic the crews back are to the direction of flight. on Landing... crews backs are to the direction of flight. In the end the laydown option has a lot of benefits... for an un-piloted spacecraft. A lot of astronauts did not like the idea of this method... Regardless of the science behind it.

Actually the Crew Return Vehicle was like 85% complete (for the spacewothy prototype) when it was canceled... It was canceled because it would add another Shuttle to the ISS launch. Not because canceleing it, itself would save money... But rather the TEST and LAUNCH of it would cost significantly more than the penalties for canceling it when it was mostly complete. https://en.wikipedia.org/wiki/NASA_X-38 Wikipedia so trust it as far as you can throw yourself... But at-least it will give you a good idea. Also it should be noted... That the Crew Return vehicle wasn't really an escape pod... Rather a way for a NASA crew to stay on station longer than the Spaceshuttles ~16 day maximum.

CKAN can be a good "easy to install" method. However it is not without problems. As you add and remove mods CKAN does not do a good job cleaning up dependencies even though it thinks they are gone for example. If you have been playing KSP for a while now @space-wizards, I suggest deleting all but the two non SQUAD folders from the Gamedata folder... then starting fresh. If you are on steam you can just delete the mod folder and then Verify file integrity in Steam. PERSONALLY I do not recommend CKAN for big mod projects like BDB. In my experiments with CKAN from it's earliest days to today it just adds to the failure points and makes it harder to diagnose what is wrong. And in my Experience CKAN caused more bugs in my complicated builds of KSP than it prevented. so for me it is manual install only. In regards to the Langley lander (the one man Gemini lander,) You attach it below the engine, and then use the move part function to raise it up so the engine bell is below the tank structure. I am guessing here but there is no hidden node because the parts are small and it would be harder to build the lander with the extra node Right up until the ISS was scaled back mid-way through construction (basically after Columbia disaster) it was planned to have a straight conical PMA for the X-38 Crew rescue/Return craft. Speed/smoothness of crew transfer and structural strength being more important than cost in this case.

Will look into this further as my schedule settles down. But a curiosity question. Do your patches support Monocoque and balloon tanks for the various fuel types. EG Agena is the purest Monocoque tank I know of, fully 80 percent of the tank is the structure of the stage. If you are using the "variable" name applied like the latest editions of BDB, it can be a simple new variable to gain the benefits of the lighter mass/unit volume of a monocoque tank.

mmm, Columbium/Niobium Blue... Pretty! Thanks again for making that happen Cobaltwolf!

Yes the F-1A could be throttled to 70%. However it was not intended for the F-1A to replace the F-1 in ALL configurations (the core MLV study showcases this by having several MLV rockets listed with 5 or 6 F-1s and grossly similar rockets with 5 F-1As. ) Most of the INT-20 documentation I used to write the article specifically cited F-1 engine and F-1 Engine thrust. This is one of the reasons I said the INT-20 was Boeing trying to spite everyone else just to keep "their" stage in production. They cut all "new" or "growth" costs out of the proposal and stuck with a bone stock S-IC for their proposal. I had only found anecdotal references to the F-1A in the INT-20. All that being said, I have recently had a discussion with other data miners / History Collectors like myself. Everyone other that me stated that the INT-20 was where NASA should have focused. To keep the S-IC stage. This is to the exclusion of the S-II stage... which to me begs the question... Whats the point? Keeping S-IC alone does nothing for your goal of keeping a major rocket in production. What it does do is keep the F-1 engine viable... There are other ways to do this that do not waste production capabilities in my book. Conversely, I look at three of the INT-x proposals as the go to because with these three, you cover payloads slightly larger than Atlas-Centaur all the way up to full on Saturn V. I call it Dial a Saturn Saturn II- INT-18.5/INT-18.7 (including 2x 4x and 5x SRMs) Saturn II-INT-19 (with Select-able M55 SRMs from 4 to 16) If this went into production I would assume some non-Minuteman SRMs would replace the M55s for Strategic Arms treaty enforcement. Saturn INT-21 INT-18.7 with 5SRMs can lift ~96% of what INT-20 could lift at 3.6G The problem with using the Saturn II rockets is the SRMs. IN the 1960s stacking SRMs is not an expensive process... By the 1980s it is hugely expensive. The Saturn II-INT-19 is the most cost effective launcher of the three. But it is also the lowest performing. But it's performance is actually better than any of the INT-18s with 2x SRMs. Ground logistics wise you end up with 3 new launch pads, and keeping LC-39 for the INT-21/ standard-ish Saturn V. The INT-18 (x2) plus INT-19 would ride on one pad, the INT-18(x4) would need a second and because of the 5 SRMs in a pentagonal arrangement you would need a 3rd pad for the INT-18 (x5.) I know the mass of a UA-1207 is pretty hefty but I always imagined that the bare rocket would be moved to the pad on a small crawler and then the empty stages (and payload) winched into place on the stand.... then from horizontal "roadable" buildings the UA-120x would be elevated to the correct point for joining the MS-II stage on the launch stand. much like you see the old coffin launched Atlas ballistic missile (and IM-99 Bomarc) elevate from low profile buildings to fire.

INT-17, the "HG-3" powered (notice the quotes please!) Needs either RL-20P3 engines in the first stage or the XLR-129s. Those are the best engines for the fit. ALSO needs LESS Than full fuel (as designed.) I wrote an article on the Saturn II a couple months back let me reference it for INT-17.... Oh and you need the 7x engine mount, not the standard 5x Engine mount. First to quote my original document: The above quote means INT-17 is at best a PIG and not really a productive Rocket. The Original document that lead to the INT-17, INT-18 and INT-19 "Adaptation of the Saturn S-II stage for Ground launch" specifically calls out that any S-II derived Launcher would need augmented or 0 stage thrust to carry a workable payload. The document cites the Minuteman SRM (AKA INT-19,) and the UA-1205/UA-1207 SRM (AKA INT-18) as well as a NO S-IVB UA-1205 rocket (Which was dropped from the actual final document. The Final INT/MLV document on the Saturn II points out that the first stage needs something like 2/3rds max fuel and the S-IVB needs something like 50% max fuel to attain orbit with a 5000lb payload (I don't have that document well sorted at the moment and am looking for it (Will update when I find it.) IE for the cost, just throw your 5000lb payload on a Delta or an Atlas Centaur and you are more efficient in $$$ to launch. *EDITED FROM HERE ON TO NEXT ** comment* So the Initial study I quoted, had the HG-3 engines in a 7x array and needed a reduced fuel load (I still haven't found the document that actually calculated it out but I can tell you Wikipedia is dead wrong if you build it with 7 RL20s or XLR-129s for throw weight. Again HG-3 was a paper engine and the 1964 document covering the INT-17 is also a theoretical paper and was never intended to make hardware. It appears that Pratt and Whitney's theoretical dream pipe HG-3 had some problems that could not be solved with then state of the art engineering, but with 20 years give or take would result in the superior turbo pumps used on the RS-25/SSME engines for the Shuttle. A latter Boeing study re-investigated the INT-17 as part of it's MLV-SAT-V3B. This INT-17 (yes lets call it INT-17A) is stretched by 15.5 or 16.5 feet (depends on the copy of the report but both numbers appear) Full fuel load and 7x J-2T-400Ks as mentioned previously by @Starhelperdude above (good guess BTW!) @Jcking of course tied the correct guess all up with a pretty bow for us MS-IVB also 16.5ft long and also with a single J-2T-400K engine. 136k lbs to LEO at 72 degrees. Report is "Study of Saturn and Intermediate Vehicle Improvement Programs: Executive Summary Report" dated 04/16/1968. This is a Marshal Space Flight Center summation of the various INT and MLV reports up to this date. *End Edited Content* Neat rockets. I should note that each vendor used their own designation systems in the MLV rockets. The only unified designations appear to be the LEO INT series of Saturn Rockets. A telling moment if you think about it for a bit.

Doing so would totally break the parts because you are adding hundreds of TONS of mass.... not really an exageration there. Embrace Hydrolox, it make the game better

Yeah, it would look better with Saturn-Titan Derived 156" SRBs instead of the Shuttle Derived 148" ones. The gimbal collar would have a flat "inside" side to it and utilize a strong-back beam between the nose and tail sections... great place for attachment points don't cha know