Zorg

thats on the list, will likely be a payload bay rather than a SAF.

Oh yeah I did see it, the thing is according to JSO the Saturn IB is such a pig that the weight of the structural parts is already as low as it could reasonably be. Perhaps there is performance margin to increase the mass for Saturn I but a mass only switch on a structural part like the engine mount (which is where it probably needs to be) is a bit of an outlier. We can think about it though perhaps after Pegasus is done since iirc that should be the most demanding payload for Saturn I?

I think you can just put one of the Delta III 2.5m to various sizes payload adapters on it. There have been many iterations I think but yes most often depicted like that. The Restock NERV is a great depiction to be fair but if we are doing Nerva II for BDB might as well consider doing Nerva 1 with our own balancing and so forth.

I do this for fun really and commissions would turn it into work

I think its unlikely we will see a lot of new engines for BDB for KSP 1 at any rate. Exotic propellants are a bit messy in terms of needing new fuel switchers and working out an appropriate stockalike balance for them and so on. While things are always subject to change, the only engines on my personal to do list are revamping the old Atlas engines, RS-X which would be derivative of work done on Atlas And er this: This being Nerva II which would be even longer than the M1. Our own Nerva I will prob also happen but thats the roadmap for me anyway. This will be part of the 2nd Saturn Apollo update.

RS-30 because its cool and I wanted to make it. Its a micro SSME literally. It uses subscale SSME components and was designed as a test bed for that purpose primarily. As a secondary purpose it was considered for the Apollo Applications Space Tug instead of the RL10. Its an RL10 sized engine with similar thrust (bit less than the latest models actually) and crazy high Isp due to the 1:400 expansion ratio and over 2000psi chamber pressure from being staged combustion. RL20 was sort of on a wishlist from Cobalt for a while, we didnt know too much about it at the time though. What really happened with the RL20 and XLR129 is that I thought I would finally make the HG-3 engine, allegedly the rocketdyne predecessor to the SSME and a mashup between the J2 and the SSME or so it seemed. When we actually dug into it in order to find decent sources (instead of making something up), particularly with the help of @TimothyC we discovered that not only was the HG-3 not a real engine design it was only an evaluative study of future engine technology requirements the conclusion being : staged combustion is the future. And it was conducted by Pratt and Whitney for Marshall and had nothing to do with Rocketdyne. The Pratt & Whitney RL20 and the XLR129 then seemed like far more *real* staged combustion designs that predated the SSME and both are again interesting and cool. The XLR129 has no connections to any rocket in BDB although the RL20 was mentioned in some MLV documents. For a more detailed rant about the whole HG-3 thing you can take a look at this post here: As for sources Astronautix is terribly unreliable. Not everything on it is wrong but enough of it is (quite a lot in fact) that you cant rely on it. And it doesnt cite its sources. I got most of the information for these engines from here. Which is hosting some scans of original documents. The documents on the RS30 and the XLR129 are particularly detailed. https://www.alternatewars.com/BBOW/Space_Engines/Pratt_Engines.htm https://www.alternatewars.com/BBOW/Space_Engines/Rocketdyne_Engines.htm M-1 of course is in there simply cos it big. And also even if not part of a canonical saturn MLV build it can be used for speculative advanced saturns.

Ah right sorry, I forget the in game names though I gave it myself Yes IRL its the RS-30 Advanced Space Engine.

You mean the RS30 I guess? It seems the RS30 had a so called tank head pumped idle mode where it could just open the taps, spin up the turbines based on propellant pressure at the tank head, and then run at very low power to both settle the propellants and also provide autogenous pressurisation for the tank. And with a spark ignitor, it seems the engine would be limited by thermal and structural loads. Based on the documents this would be 60 thermal cycles (a startup to any power level) between services and 300 cycles between full overhauls. You've reminded me that I never did the engine ignitor configs for the hydrolox engines so I'll go ahead and configure them. M1 will be quite simple and limited to a single internal ignition so it can be air started. RS30 will be 60 starts and no ullage requirement. For the XLR129 I found this: durability 10 hours time between overhauls, 100 reuses,300 starts, 300 thermal cycles, 10, 000 valve cycles. However, on a single flight the XLR 129 would be limited by helium pressurant from the main stage tanks. Plus the figures are for durability between overhauls and doesnt mention servicing between them. Additionally, I found "Multiple restart at sea level or altitude" but no further detail. Given the purpose of the engine, and being sort of an SSME contemporary, I am giving it a what I think is still very generous 10 starts which is a lot for an engine of this type from the 70s on a single flight. No figures for the RL20, but the stated durability goal of 10 hours TBO is similar to the XLR129 (no further details known). I am giving it half the XLR129 being an older iteration. So 5 starts. If anyone finds more detailed information, or have some stronger basis on which to re-evaluate the restart capability of the Pratt engines I'm happy to reconsider.

0.625* real world diameter rounded to nearest KSP size. When existing KSP sizes weren't appropriate we made new ones like 1.5m 5.625m (old S1C etc), and the new sizes for saturn, 4.25m and 6.25m Most probes are exactly real world * 0.625 Engines are same Isp, 1/4 of real world thrust, mass adjusted to an appropriate TWR. KSP TWR in general being much worse than real world. (most stockalike mods use 50% thrust for upper stages but we use 25% for all). We try to scale engines x0.625 exactly and adjust mounting rings etc to fit our engine mounts. There are exceptions here and there.

its meant for the next release with the various probes but the stuff master branch gets merged upstream to saturn branch regularly. Its up to date as of today.

Yeah you're expected to use the radial attachement point.

25Kw power tower addition if they had been able to perform the Skylab reboost. I am planning to make this for the second phase of skylab stuff. Would suggest looking here: https://www.spacelaunchreport.com/thorflew.html

I personally mostly enjoyed the show for what it was (s1 at least), a Ronald D Moore show about social issues with some space related set dressing But regardless of what one may think about the quality of the show, the thing is that there are a lot of real world whacky advanced apollo/saturn/skylab stuff we could be (and we are) doing as opposed to stuff from FAM which ultimately does not even turn out to even work once we look at it critically in terms of balancing etc. Again I never expected that level of fidelity from a tv show like that but we do for BDB.

While they havent gotten around to it yet, @Invaderchaos should have a clear idea of what experiments and what balance should be on the Pioneer parts. I would not bother with a pull request at least not without discussing with Invader

Most of the content for an initial release is in the dev branch already. This is not a firm commitment but hopefully early next year. There's more Saturn, Skylab and Apollo derived stuff to come but once we have managed to catch up in functionality to the old parts we want to put out a release and then work on weirder more speculative stuff for a subsequent release.

A really speculative configuration for BDB_Extras that meets the upper end of the HG-3 study parameters (300k to 400k lbf thrust) would be a large bell XLR129, final production SSME config. That is to say during the SSME competition the XLR129 based P&W model had components tested at 350k thrust, at the time the competition called for 400k lbf. The 350k config is represented in BDB main but if we speculate that P&W won the competition under those conditions it seems realistic they could have met the thrust target. ps. They lost on the basis they could not match the 500k + revised target and it seems questionable they could have achieved that but 400k seems feasible.

Oh @CobaltWolf would need to answer that but given that he didnt include it to begin with I doubt it. The cost in texture space for something like this is much higher than it was for the F1 insulation.

Yeah I meant more that mesh wouldnt necessarily fit together nicely with the S4B mount. Though they are similar theres some pipes and greebles and such on the S4B version thats not on the Skylab version so the baked ambient occlusion wouldnt match up.

nah they live in different part folders. not really feasible to combine assets and the greebling is specifically skylab stuff. yeah we plan to do something for it.

1/2 Not based on anything specific but just for legoability an alternate mount for SII with a 3.75m base and a custom mount for the M1 to attach there. Will try to add a few more options to the upper part later using some smaller mounting plates I can switch around. We can add some options not available on the original SII mount.

Those variants are coming soonish. Both orignal SOFI, and more technically accurate treated Atlas V aluminium styles.

Really cool seeing the CADS on Habtech parts

Just want to confirm if this problem only exists with the hinged SLA or the jettisionable panel version as well? We dont know why this is happening. The IVAs are all old ones which needed to be rotated to match the new models and this is done via a custom module in the BDB plugin. It seems to be failing under certain conditions. I need to see if its possible to rebuild the IVA in unity with the correct orientation to begin with for a clean fix.

We’ll look into the potential SLA issue. Not had a chance to test yet.

I havent tested the new Saturn I/IB, I guess I should soon and see if anything is up. But I will say that PVG is developed for realism overhaul so more realistically behaving BDB rockets shouldnt be a problem. The vast majority of PVG problems are user error and sometimes craft error, either in the build or in the parts themselves. It sometimes isnt straightforward yes but it is a fantastic implementation of closed loop guidance in KSP but it does need to be deployed appropriately. ps. the small scale of the system (2.7x vs 11.whatever for realscale) also makes PVG behaviour a bit odd sometimes for higher twr upper stages though rarely unusually so.