Zorg

As per current plans, Invaderchaos will tackle Atlas V separately when he has the time to do so. My work is focused on the classic balloon tank models up to Atlas III. The RD180 has been modelled with the Atlas III mount and I will make the Atlas V mount after coordinating with Invader when its being developed.

Replacement. The Atlas parts are the oldest rocket parts in the mod, the aim here to revamp, replace and expand on those parts. We consider the Titan revamp to be point at which the current art style and standard to have been established. Pretty much everything made since then can be considered "final". The Atlas parts are older. (sidenote although the SLV-3X Fatlas parts are technically newer, they were made to match the older parts so they will need to be redone too).

Atlas E/F

Make sure you have reflections turned up in the KSP graphics settings. (I'm assuming you have Textures Unlimited already installed)

I haven't decided yet. I like the idea behind the way you did previously and it makes sense to differentiate balance wise. However adding that tag would complicate the ability to create some interesting Atlas test flight variants that had markings around decoy and scientific passenger pods. My thought was to make decals for those since its not feasible to have all those as texture variants...

It could be a bell from a sustainer, the very first LR105 was not aspirated, just had the exhaust off to the side based on the illustrations I've seen. Don't have a photo of a full engine though.

Interesting, didn't know about this tbh. I've got a fair amount of Atlas A pics in my refs but none of the conical nozzles. But probably not worth doing even if I had though, if as you pointed out only a handful of flights used them.

Gas generator exhaust pipe for the booster engines. As for why the shape changed? Who knows... theres a million small differences among different Atlas variants. This was one that I happened to notice and was feasible to model due to the way the meshes and textures were split The pipe is positioned where it is since the turbo pumps for the booster engines were located centrally in the skirt. The early MA-1 power pack had a shared turbo pump and gas generator for the boosters, from that point on they each had a separate pump (but still co-located in the center of the skirt) but shared gas generators. The exception is the Atlas E/F engines, the MA-3 pack, where the USAF wanted the engines to be easily removable for maintenance independently. So those engines are completely separate with all their machinery located near the engine bell like a typical engine. This is also why the Atlas E/F booster skirt is significantly different in shape to accomodate the bulkier engine package. Here's an Atlas F with independent boosters You can see the Atlas E/F skirt shape on the far right here (this was before I modelled the pipe on the other skirts)

It was an actual scheme on some Atlas A launches. (I need to recolour the top of the avionics pod, it was a bit faded in the reference picture I was looking at earlier) Atlas 10A on pad--Tower Away box by SDASM Archives, on Flickr I believe the 4th picture I posted answers that question already

Some more Atlas updates the chronological order is reversed here, from left to right: Atlas D, C, B and two version of Atlas A. Of course all the other core tank variants such as the derivatives of Atlas D, E/F, II, III all to be done so loads more work lol.

The plan is to make a separate dedicated texture set for TU. Like we did for CM and Skylab. It may have to be in extras since it means doubling the texture size of Atlas otherwise.

Oh forgot to post this, still a lot of work left on Atlas but some of the texturing work has started (other stuff remains to be modelled). Fun little effect on the normals

Work on Atlas continues at a slow pace. But it is continuing. GSE cutouts and more details on Atlas A and D skirts idk if I posted this before but the standard aft tank A new aft tank just for Atlas SLV-3X "Fatlas" so the H1-D can actually fit on it properly (you need to rotate it 45 degrees though. And a preview of the new tank setup thats been planned. The annotation here isnt comprehensive. For example Atlas H MSD would be a base tank + SLV3C (&D) cylindrical extension + Atlas H conical adapter. An SLV-3A would be base tank +SLV 3A extension+ 0.9375m conical extension etc.

Oh the engine pages werent there last time I checked, hope it gets uploaded at some point. But yeah archive.org was able to recover most of the pages on the old site I think.

HG-3 was a NASA designation and the main public reference available has NASA contracting out P&W not Rocketdyne to perform a study of what the future of rocket engine development should be. Though its possible Rocketdyne also participated in some aspect of the study I've found no first hand source for that, we do know at the time they were doing a lot of aerospike and J2 nozzle studies. The timing of the study seems to be between the RL-20 and XLR-129. The study mostly concludes staged combustion is good and doesnt have any real designs associated with it but the RL-20 is a good analogue for that notional engine as like the HG-3 (as conceptualised) could be a drop in replacement for the J-2. I wrote down everything I found out here: You can find more background on the RL-20 specifically in the link above too. The best reference online was Alternate wars but thats down now so I just have a few images and (maybe PDFs) saved from there lying around. But that post summarizes everything.

I'll need to double check on the staging, dont remember what sources I looked at for those configs. But pressure fed does not necessarily mean ullage is not required. Most pressure fed rocket stages for which I've found information show that they need ullage including the Apollo LM and CSM (seems like very small propulsion systems used on probes and satellites didn't). I do remember I found some specific information about a (version of?) Agena that included a sump tank for engine start that specifically ensured that it didn't need ullage and that's a pump fed stage.

This is just a config thing so can be done fairly easily. If someone could put this issue on github it will serve as a reminder when I can get to it.

For me, something of a break for various reasons. I did post the finished LR101 model last month but that was the only progress I made in a few months. But hoping to get back to Atlas after the new year.

Its still on the cards. I was hoping to continue Rodger's work if he's not going to work on it further. But I've not had much time for modding lately and when I can resume I want to focus on finishing Atlas. So it will be a while I guess.

I made a mistake, I was just recalling some WIP CM IVA stuff Rodger had posted but it wasn't actually finished.

So this still needs a little tweaking in terms of the positioning of some of the bits but since I havent posted any progress in ages so here you go (yes Atlas is still happening and I am indeed alive). The shroud is a placeholder for the moment

Incredible!

To elaborate on what @Pappystein wrote, this was Pratt & Whitney's proposal for the SSME, competing with Aerojet's and Rocketdyne's (who won of course). It was derivative of their earlier work on the XLR-129 and in fact early on in the program when the thrust requirements were a lot lower, I believe the initial proposal was more or less an XLR129 and what we see here is a mockup of a later uprated and enlarged version. Throughout most of the program, P&W were considered the leading candidate as they had been working on staged combustion ideas long before the shuttle program, first through the RL20 concept and then the XLR129 which had components tested on the stand (for the ISINGLASS rocket powered boost glide spyplane). You will find a lot of the earlier Space Shuttle concepts from various contractors outright mentioning the XLR129 as the baseline engine. The thrust requirement from NASA kept rising though when it got to over 500k lbf, P&W were really struggling while Rocketdyne shot ahead to frontrunner by demonstrating an engine on the test stand at the required thrust level. However the chamber for this test was fed by fuel pressurized directly from the test stand and didnt have functional turbo pumps, I guess they thought they would figure out the turbo pumps later! Much to P&W's anger Rocketdyne won the contract despite their protests. As it turned out the early SSME was plagued by turbo pump issues which werent fully resolved until NASA hired P&W to fix the pumps Anyway its a strange tale of what might have been. The engine in the strictest sense isnt really within the scope of BDB. I suppose but I made the original XLR129 as part of series of oddball hydrolox engines as Cobalt had always wanted some of them in the mod (not the XLR specifically but M1 and RL20 were mentioned long ago). And since this is related and because I like It I might still do it someday. ps. more general comment re lack of Atlas updates, been a bit preoccupied but hopefully can resume work on it soon!

Um no I dont think I have the time or motivation to do that. I *would* like to do the actual SSME candidate version which was a fair bit bigger and does have a boattail mount type thing. But not sure when (plus I dont have good refs as the layout is a bit different but its a maybe for someday).

We dont scale payload weight using the 25% rule. As a baseline we take the IRL mass (excluding prop mass) and then adjust as needed for performance. We will take a close look at this sort of thing once the lander is available. But its not unknown for us to use IRL thrust or even overscaled thrust where necessary ( I think the peacekeeper Post boost vehicle has overscaled thrust, and I dont remember exactly but the LMAE and LMDE are I think somewhere between IRL and 25%). Anyway rest assured we will work to find a good balance between having an impression of the real thing and usability.