Project CST-100

[N_Molson]

Looks like I'll have to work on the VC some more..

Have you a .msh version of it, even if not finished ? I think it would help to make the capsule less erm transparent

Another temporary option I can do is to put a matte black cone inside, its a way to do it...

 

[Urwumpe]

Have you a .msh version of it, even if not finished ? I think it would help to make the capsule less erm transparent

Another temporary option I can do is to put a matte black cone inside, its a way to do it...

Better use two inside meshes: One coarse for looking from outside, and a detailled one for VC mode.

 

[N_Molson]

Better use two inside meshes: One coarse for looking from outside, and a detailled one for VC mode.

Yes, that would be the ideal option in terms of FPS-saving. Well ky, do what you can with the time you have

 

[ky]

Have you a .msh version of it, even if not finished ? I think it would help to make the capsule less erm transparent

Another temporary option I can do is to put a matte black cone inside, its a way to do it...

I think I posted a link a few pages back, but let me check to see if I uploaded it to mediafire

 

[N_Molson]

I think that the version you posted is the sketchpad one (.skp)

 

[ky]

I think that the version you posted is the sketchpad one (.skp)

It was, I'm going to upload it as soon as I log in to my pc

 

[francisdrake]

An abort thrust of 4 x 258 kN fits quite well. For a spacecraft mass of 12 ton this gives an inital acceleration of 79 m/s², which is fairly cloase to the 72 m/s² of the (planned) Dragon LAS.

I'd guess that the LAS-thrusters would not be used during orbital maneuvers, only the separate forward pushig orbital thrusters, located in the doghouses. The LAS thrusters could be discarded after the launch phase, but I guess making the high pressure feed system and engine supports severable would make the system unnecessary complicated.

 

[MaverickSawyer]

Could they be used for deorbit manuevers? After all, if you're not going to abort, might as well use the propellants somehow. Maybe only two Bantams light off...

 

[ky]

Could they be used for deorbit manuevers? After all, if you're not going to abort, might as well use the propellants somehow. Maybe only two Bantams light off...

Wouldn't it be somewhat uneven?

 

[N_Molson]

An abort thrust of 4 x 258 kN fits quite well.

From what said above, we can safely add the 134 kN of the OMAC thrusters. Adds a good 10% of thrust.

Wouldn't it be somewhat uneven?

Given the shape of the thrusters and their orientation, I'm about sure they can be gimbaled to control the spacecraft during the abort.

Could they be used for deorbit manuevers? After all, if you're not going to abort, might as well use the propellants somehow.

We concluded above that all the SM thrusters share the same propellants, which indeed makes much more sense, before that I wasn't understanding the point of such a system. So once in orbit, only the thrusters themselves are dead mass, and they probably aren't very heavy.

 

[francisdrake]

Wouldn't it be somewhat uneven?

To reduce problems with uneven firing of the abort engines, they are angled outwards, so each thrust vector points approximately through the spacecrafts mass center.

In case one engine does not light up (or underperforms) the resulting force vector will push the spacecraft somewhat sideways, but will not lead to an uncontrolled rotation.

By angling out the nozzles some forward thrust is lost, but this is minor.
For 20° angle the loss is 1-cos(20°) = 6%.
About 200 m/s are needed for an abort, while we estimate the service module to have 400 - 500 m/s in its tanks.

 

[Urwumpe]

The tanks will likely have enough for an orbital mission on board, which is closer to 300 m/s. Which is still enough for an abort.

Also, it looks like the engines can be gimballed - at least some details on the renderings look like there are gimbal actuators installed.

 

[N_Molson]

Some texturing and meshing work on the Centaur nozzles again :

Still not perfect, but closer from reality.

Edit : I have to learn how those environnement maps work. They could make that chrome-engine-plumbing look really cool. It's almost impossible to have something that looks like chrome without reflexion.

---------- Post added 04-30-13 at 02:01 AM ---------- Previous post was 04-29-13 at 04:37 PM ----------

OK now this is getting interesting. I've put too much of it to see how it works, of course, but it looks soo nice ! Perfect for the engine plumbing.

I don't even understand how it can work so well without major framerate impact. Hail Jarmonik !! :hail:

---------- Post added at 12:27 PM ---------- Previous post was at 02:01 AM ----------

Yes, I think I begin to like it that way, still lacks some detail but we're getting there :

A decent preview of the Centaur/CST-100 combo :

 

[PhantomCruiser]

That 3rd one has to go in the manual, awesome job and great screenshot!

 

[ky]

Boeing has nothing on us (Except money, resources, etc)

 

[Urwumpe]

Well, the engine plumbing would likely be a nightmare, the RL-10 is not really simple. But then, you could at least make the combustion chamber the proper size and place the pumps in the proper shape and orientation

I think the important detail of the engines are the two U-shaped sections of the plumbing.

 

[N_Molson]

Well, I'd say that the engine model itself is hardly 50% complete, a lot of the plumbing is missing. The size of the combustion chamber is ok*, as I've used a schematic to get the proportions. One engine is mounted in the wrong direction, yes. The problem about that is that the 2-engines version flew only one time (1998 or so), and even then it wasn't on the Atlas V. So it's very hard to find good pics of the layout, and pics of the engine alone don't help for that (in fact it's like "hmm, where that end should be plugged where ?").

See what I mean ? :shifty:

Then there is also all the wiring at the back of the Centaur, which is a real maze of cables, relays and boxes. Currently only the RCS system plumbing is modeled.

Also I'll have to make the SE version, and also the optional mission duration expansion packs (more He tanks for more restarts, more RCS for the additional ullage burns, heavier but more durable batteries). Maybe also different variations of insulation which would have an influence on the empty mass and the boiloff rates. I already found info from L-M about that.

There's a lot of work on that second stage. Ideally, it will work as a "stand alone", so you'll be able to use it with other rockets, or in a shuttle bay...

*On the above pics, the engines have not the extensible nozzle feature, or it has been removed, so the proportions look different.

 

[Kyle]

That pluming does look hard to model. I really wish I was better at mesh making, otherwise I would help out with that to save time.

 

[N_Molson]

If you want to help, you can also search for good pics of centaur stages, single or dual engine. It is quite time-consuming for me to search for that. :tiphat:

Of course some people do it the easy way and hide everything interesting behind a fictional casing (also notice the wrong shape of the nozzle) :

 

[Urwumpe]

I think the fine plumbing could be replaced by semitransparent textures, not really necessary to do. But of course: The violet and the red stuff in the centaur photo is removed before installation (violet) and before flight (red).