Project XR2 Ravenstar - Mk II

[Coolhand]

It does have mounting points, it has always had them.

As for the interior... Of course, it could be a cattle car, but as i said that doesn't make sense on a longer voyage so a less populated cabin will better meet the majority of requirements whether moon or LEO.

Finally I would encourage you all to share your settings and scenarios, whether extreme or sedate. And to criticise those settings is like critiquing someone's graphic equaliser settings, entirely personal preference; in the context of orbiter they all work regardless of you own interpretation.

 

[Keatah]

Is the number and positions of the passenger seats configurable? Is there (or going to be) a paintkit for the inside, or part of the inside?

Perhaps there could be a way to project the output of another running windows application onto some surfaces inside. That way we could watch sci-fi movies IFE style.. yeh! I so much wanna make this into a party bus with women and everything! And it would be perfect, it doesn't matter where you go, as long as you're going!

 

[Cras]

Finally I would encourage you all to share your settings and scenarios, whether extreme or sedate.

This is a great idea, because while I have done this (well I mostly have used the presets, like making the O2 always weight its full weight, require the payload tanks for full fuel load), I am very interested in our more mathmatically inclined collegues how they transform the XR2s configurations to match certain criteria. This is something I intend to do myself, but inspiration and examples are always welcome!

 

[astrosammy]

Well, I created a special config for SpaceShip2 like suborbital missions. Good if you want to fly a short realtime mission, as you will be back on Earth in less then 15 minutes.

 

[Axel]

I wrote a realistic near future configs for all XRs and its possible to reach LEO!!!
All i changed for the XR2 was this:

MainTankCapacity=65000.0 ;increased
ScramTankCapacity=5350.0 ;decreased
MainFuelISP=4750.0 ;strongly decreased, its pure chemical now

All other config values i did set to realistic, where possible (in the options before). But no extra payload is possible and we need intensive RCS burnings or crossfeeding from the RCS tank to the main tank for reaching ISS.
For some tons of payload or higher orbits we have to use a carrier craft, a 747 ect. I like this very and what we do want more, as a 100% reusable passenger shuttle for LEO, without exotic SciFi fuels or nuclear reactors?!!

A queston to Coolhand: Did you ever thought about a freighter version of the XR2? With only 2 pilots and a longer payload bay, STS-like?
I know we have the "XR5 semi status shuttle" (because with no cockpit again ), but the XR2 would be cheaper for smaller cargos.

 

[Cras]

Interesting that you bring up the Payload Bay, because I have often come to hard decisions when planning out my future missions and what I can do with teh XR2MK1 as an STS replacement.

First being, the cargo bay in the XR2 is not big at all, andif I want to build a space station, I need to launch the node up on a Jarvis or a Quasar, and then meet up with it, and then take it over to the Station, since I can have it sit in the payload bay in orbit with the bay doors open, (something I avoid doing when I turn the payload bay into a giant fuel tank, to protect it from space).

A question for you Axel, how do you use a carrier craft in Orbiter? So far, I have used Energia to launch XR-2 into Orbit using realistic settings (I have yet to touch the Main fuel ISP, but that was at the top of my list in getting even more real tech performance.). But the idea of using a carrier craft means I can utilize the Scram engines, something which I almost never use since Energia provides ALL the energy required to get into LEO, and I only need to perform an XR-2 equivalent of an OMS2 burn once up in space.

 

[Axel]

@Cras
I try to avoid a carrier craft, as mutch i can. Then a carrier makes every system more complex. But when i use it, i use a boing 747 or Valkiri with universal cargo deck 4 to connect. A Valkiri can reach speeds, that you can activate XR2's own scram. But i like ships when they can reach space STTO from the ground and the XR2 can do this definitely.

What i try next is a external tank for the XR2, i will use the tank from the starclipper68, (shown in my profil, my absolut favorite ship) because both ships are very similar in size, the starclipper has more empty mass, good for the XR2 :thumbup:! The ET from the starclipper68 can take 270mT fuel, so that you can reach space very easy, without any thermal or aerodynamic problems.
And that all with the good old direct H2-LOX burning method, the "muscle-car-high-acceleration-method". I will also deactivate the SCRAM jet then and give the XR2 the full internal main tank mass.
If the starclipper tank is empty, we should be near orbital velocity and have a full internal tank, like your Energia method, for very high orbit changings or payload. I know its no real STTO then, but its an 1,5 staged vessel and it uses its own engines all times. We save expensive SCRAM developing costs and time. And nobody can say if a SCRAM jet really works for a spaceplane. There are mutch problems to solve.
The starclipper68 had flown in 1968 when Lockheed would was the winner and not Boing.

For bigger payloads i use the XR5 or TX5, or a shuttle derivated launcher for really big payloads up to 150 mT.
The XR5 in its original setting with some hundrets mT payload is completly SciFi, you can reach max 50-70mT with real settings, but that should be enough for most missions. The XR2 is only a passenger shuttle and you are right, its normal payload bay is to small. ITs only for small support flights.

@Coolhand
So the streched XR2-MK2 in an extra pure payload freighter version would be a good compromise, for 80% our missions!!!
Think about it Coolhand! Then what is it what we fly in orbiter mostly and what we can use and see? Payloads!

 

[Cras]

Thanks for the info Axel. I see a lot of people say the best way to use SSBB is the XR5, but so far for me the XR5 is just too much for me to believe. It is very cool that is it so darn big, but I am looking for something a bit more realistic. Not 100% so, because when I am looking for that, I just fly Shuttle Fleet, and when I treat the XR2 as a STS replacement, it is trade off the payload capabilities for a space plane that can leave LEO (I have no problem taking the XR2 to the Moon for instance.). One thing I can do with Energia is have one side mount the XR, and on the other that giant ride along fairing that I can stick what ever payload I want to manipulate in orbit. I have yet to try this, as I am still in the Shuttle phase of my current history rewrite, but I would need to attach a RMS arm to the XR 2 so I can go grapple the modules and put them in the payload bay.

And external tank sounds very appealing and this I also will check out. I thought about a carrier craft in the past but never followed up on it because it never appealed to me as much as external tanks or just flat out booster rockets. I did start to look into using one of the DGIV launchers that are up on Orbithanger and instead attach the XR2 to that.

One vehicle that would be appealing also is the Quasar SHLV, but with it being multistage, and it having a very poor autopilot (the Energia's launch autopilot is fantastic), it would require use of UCD and probably also Universal Auto Pilot to deal with the launch.

 

[Grover]

RATO or RAC (rocket assisted climb) is the way to go, just put some tanks and/or rockets onto external hardpoints, then fire them up and drop them when they run empty... and make sure that the descent trajectory doesnt land the droppings on top of anything... bad for insurance premiums

 

[Coolhand]

A cargo version... yeah i've thought about that of course, as way back as right at the start, and its been suggested before, infact all of these things have been suggested before over the last 4 years and many are already accommodated in the design.

So if you mean a large, open to space payload bay, I don't recall a huge demand for that.

While it sounds like a nice idea, unless everything you want to take up is long and thin and flat it would be pretty redundant as all the loads would have to be custom made - who is going to do all that? Take a much larger vehicle that can launch shuttle bay type loads (of which many already exist) and it will work far better in Orbiter...

In real life even, It's akin to using a Learjet as a freighter. While it might be done, I just don't see it being a common type.

Practically, I'd have to redesign a lot of the ship, remap and repaint portions of the upper texture, completely re-map and repaint the cargo bay, again... Ditch all the work i've done so far on the interior, all the interior maps.

It's not a trivial task and would cause months of delay.. and at the end of the day it wouldn't even be that useful so I don't feel it's a very realistic suggestion.

 

[Coolhand]

And while we're at the topic of Mk2's that never were, here are a couple of mockups i tried out, before settling on the new form i did try a lot of things out - even including a payload bay that was much larger and went all the way back. Almost like a super-guppy conversion only less so - which would probably make axel squeal with delight, but it was very rough - just a new surface placed over the top to assess form but it looked stupid and was never a serious idea.

I have looked for a render of it, but perhaps I never made one. Probably a good thing - enjoy the whacky 4 engines, fastest ship in the fleet.

 

[TerraMimic]

Wow, that 4 engine model is actually kinda awesome.

 

[Cras]

Those Mk2s that were not to be are certainly interesting, but I fully believe you made the correct choices for the final design.

 

[Hlynkacg]

I really like the lines of the 3 engined one, I wonder how it would look if the scramjets were moved to the wing naccells and the central engine became your single primary rocket.

Edit:
The belly "hump" formerly occupied by the scramjets could contain the thus-far absent proppelant tanks

Not that I'm complaining in anyway, the XR series is still one of my favorite addons by far.

 

[Coolhand]

Thanks fellas, As I said before, there are plenty of possibilities for other layouts, all with their advantages and all with their drawbacks. Had I been left to my own devices I think the mk2 would have ended up with 3 engines, and probably with the outer engines being a bit smaller and probably a different design to prevent it looking over-engined.

But Doug was not sold on the idea, and probably rightly so and probably its just making him more work for no actual benefit. So i capped off the 3rd engine mount with a tailcone and called it a day on the layouts at that point.

So it is what it is, and although I say so myself, I think its turned out as a great design and in fact also a practical, plausible design, as best as i can accomplish at this point. distinctive and different enough to stand on its own, while still being familiar to fans of the delta glider and fitting somewhat with the already established Altea lineage.

If anyone thinks that it isn't any of those things then I consider that personal opinion and I don't really care about that, it's basically nit-picking and plenty of people seem to enjoy it going by the tens of thousands of downloads it's had.

While no single design can please everyone I'm certainly not interested in design changes and after 4 years of it, i'm sure you guys can understand, I will be glad to eventually draw a line under this project and call it concluded... Doug will of course be supporting it for years to come as he maintains the entire rest of the XR fleet.

 

[Keatah]

As it is, we don't need any more changes. No more 4 engine variants or stretching this or moving scrams.

CH: If you're going to make any more changes, just stick to the tiny details such as wiring in the docking port, or things in the interior like fabric stitching or seating arrangements or window trimmings. Landing gear bay hydraulic lines or radiator details. Texturing stuff. You know things like that, but not necessarily those.

WE'RE DONE!

 

[Coolhand]

WE'RE DONE!

Don't say things like that, you will get them excited :lol:

In terms of modelling, yes i am done with that. just about.

Mostly what remains is a UV mapping job for the airlock, interior, bow acccess, stern access & engine access corridor.

Then these areas need to be painted.. Then I'm done, then i can retire and live off the donations (currently running at 0 dollars!) and never work again.:lol:

Then Dougs job will begin when he has time for it. Then Doug and I will argue over settings and features for a month or two, or however long that takes then its the alpha phase where i will work on the shaders and test it. Then the closed beta and then the public release candidates.

Easy, eh

 

[Cras]

So, release on Tuesday then?

 

[White Wolf]

i plan on making a donation at some point. problem is i just bought a new car and its already having mechanical issues... go figure.

enough about me, new interior looks great. that's definitely more room than the Apollo astronauts had so i can see that being viable for long range travel. hope you like dehydrated food

 

[Keatah]

There will be a prize when all this is done. Absolutely thrilling!