[WIP] R.E.L Skylon C2. Alpha Released. FAR config broken. (08 Dec 2014)

[Scarsz]

I'm more than happy to do some testing for you. I can also set up some Realism Overhaul MMs so when FAR and DRE are ready. Is Joint Reinforcement still necessary for a stable craft?

[CaptainKipard]

I'm more than happy to do some testing for you. I can also set up some Realism Overhaul MMs so when FAR and DRE are ready.

Thanks and thanks.

Is Joint Reinforcement still necessary for a stable craft?

Good question! I don't know but maybe you can ascertain that for me. I always have it installed, and I never tried flying it without it.

[Orange_Ignition]

i can help test, i use a few mods but can start stock and work my way up adding mods and see what breaks it if that is what you'd like.

[CaptainKipard]

i can help test, i use a few mods but can start stock and work my way up adding mods and see what breaks it if that is what you'd like.

But do you know how to test? It's not like tightening up the graphics on level three.

[Orange_Ignition]

But do you know how to test? It's not like tightening up the graphics on level three.

I like to think of it more like trying to find a box of self-sealing stem bolts in warehouse 3, except i don't know where warehouse 3 is or what self-sealing stem bolts actually look like...

Joking aside, I'm not sure if I'm as professional about it as i can be, but i find that im pretty good at breaking things(not the explosion kind, although that's bound to happen too) and know when i need to supply the info/opinion you (probably) will need.

I'm familiar with how things work in ksp(on at least a basic config level), i frequently tweak my own game to suit my needs or change things in mods i use, so i can find my way around config files and the MM configs. But i'm new and untested here, so it's up to you I don't mind either way, im still going to be playing the game regardless whether it's testing some neat creation of yours or just trying to find something new to build/fly. But i do sense you are looking for some... specific testers so maybe i'm not exactly it.

[CaptainKipard]

I got a few requests to test the mod from non-modders, so maybe I'll just release the alpha for everyone.

I'm still configuring things and I've come across this issue. The intakes get different amounts of air.

But still managed to get it into a high orbit, with no cargo. Loaded tests to come.

Edited November 24, 2014 by Cpt. Kipard

[Virtualgenius]

Alpha release yes please I am sure I can break it and provide the logs you need

[MightyDarkStar]

Can't wait to try it!!

[Legion_Alpha]

I'll alpha-test this if you want.

I can also help with configuring (not the anims though) and I might be able to create the module for it (depends on how long it takes me to learn C# which I am currently doing). About DRE, the module is simple. The direction line has a set of coordinates, ordered as x, z, y. Z is usually -1, to point downwards. The reflective line accounts for the heat being dissipated, and the value is in a decimal (0.05 = 5%, 0.72 = 72%). The rest is somewhat simple, and there are comments in the code to tell you what to do.

[CaptainKipard]

More tweaks to the engines, control surfaces, and wings, and I managed to take a full orange tank (with some extra parts) into a 90km orbit with about 1000m/s dv to spare. I'll have a look at the real Skylons maximum altitude and decide whether to keep the resources that remain for higher orbits or not.

It flies really beautifully now (it was designed by real engineers afterall). I'll need to write a short guide for it though, otherwise people are bound to crash it a lot, especially on takeoff and landing.

The last thing left to do is add some reaction control systems, and I'll release an alpha/beta/whatever, then finish it.

Edited November 24, 2014 by Cpt. Kipard

[blowfish]

It has come to my attention that you guys need a longer runway to test the Skylon on. So here is an early WIP base I've been making with a 4km equatorial runway (download via DropBox). Requires Kerbal Konstructs. Once you have this installed, you should be able to select "Kermin Air Force Base" as the launch site.

[CaptainKipard]

Thanks blowfish.

Actually after the latest tweaks I can get the plane to take off from KSC, but only by running the plane past the end of the runway and taking advantage of the slope after it. I'm hoping a longer runway will let me get enough speed to take off normally.

[Ralathon]

If it flies once you reach that slope the problem isn't takeoff speed, its Angle of Attack. The problem is that the craft is horizontal, so the wings can't bite into the air.

To solve it you need to have your rear wheels closer to your CoM so the control canards can tip up the nose, or you need to lengthen the nosewheel a bit, so the craft has a slight angle as it builds speed.

[CaptainKipard]

No, no, there's no moving the wheels. The craft is what it is. I'm not going to change the design of a real plane. The aircraft does lift it's nose without problems, but the real Skylon must reach ~160m/s to take off. I'm close, but not quite there. The real Skylon needs an extra long runway for that reason, and so does this mod.

If that doesn't work then the actual problem is either mass or the lift coefficient of the wings.

Edited November 24, 2014 by Cpt. Kipard

[White Owl]

...or you need to lengthen the nosewheel a bit, so the craft has a slight angle as it builds speed.

Even if this craft weren't a replica of real planned vehicle, with all the dimensions predetermined... this thing you suggest is absolutely horrible airplane design. It's sloppy, ugly, unrealistic, and a dirty hack instead of fixing the problem properly. I cringe every time I see it in KSP screenshots or videos.

If the airplane won't lift the nosewheel during the takeoff run, that means either the center of mass is too far forward of the main gear, or the control surfaces aren't giving you enough pitch authority. Kipard says the CoM is good, and we can't move the wheels. So we're left with pitch authority. Either the canards don't have enough lift, or the plane doesn't accelerate to rotation speed in the runway available; two different ways of stating the same problem, really.

And anyway, we're told the Skylon lifts its nose okay. So that's not the issue.

[camlost]

I see you finally made it, congratulations! Since all the models are done, I suggest that you publish the parts immediately, hopefully under GPL or alike, and put it on github. Let others who are good at configuring instead of 3dmax, like myself, worry about the configs.

I'm saying this because the real Skylon only makes sense on Earth, which requires 6000m/s delta-v after switching to rocket mode. As a result you need 85% of the take-off weight as fuel. Also you need to spend about 1/4~1/3 of the LH2 during air-breathing mode(Squad's jet engine code needs an overhaul aka AJE). Given the low density of liquid hydrogen, the tanks are huge (6.4m in diameter, about 70m length). This tank, thanks to its massive size, also becomes a lifting body.

However on Kerbin, this design doesn't make sense at all. It's so much better and easier to just make a regular plane, plus the jet engines being ridiculously overpowered. I'm curious what's your method of balancing for a stock game, because I think that doesn't even make any sense. Seems the tank contains 40000 units of LH2, which I presume is an arbitrarily chosen number?

It would be a pity that such an interesting design is just being eye-candy without telling us something about the physics. This I blame Squad for the planet being to small, the air being soup, the jet engine being OP and many other problems, also for instead of trying to fix any of those, they're building barns and feel good about it.

[CaptainKipard]

I see you finally made it, congratulations! Since all the models are done, I suggest that you publish the parts immediately, hopefully under GPL or alike, and put it on github. Let others who are good at configuring instead of 3dmax, like myself, worry about the configs.

I'm not sure how to respond to that politely, so would you like to rephrase that whole post? I already have my preferred license, so that's not up for debate. You're welcome to write MM configs for this mod.

[ozraven]

I admit, I've checked this thread's OP a few times and always thought the Skylon design was not to my taste. However, today I looked through the Skylon User's Guide and read about its operation and potential capabilities and now I'm smitten. I'm looking forward to your Alpha release! If you want another modder/tester (and hopeless MM/.cfg tweaker), I'd be happy to help with your testing.

Also, thanks for the threads sharing your learning and discovery of setting up the various parts. I think they make a wonderful resource for modders.

[Climberfx]

Hey Cpt. Kipard. I was preparing myself the do a version of this amazing ship when i was reading and seeing about it, researching and digging here, until in my last goggled your page appears to me.

Amazingly done Sir. So i will don't need to do it myself.

So, in that way, i can put myself in your hands for some try outs/help on testing and texturing it. I use FAR and DR here. And i'm on a Mac.

And i can help do to the textures, if you could export to a format i can read on Maya (Maya use .Mb and .Ma, but it can handle .FBX and .Obj).

But the texture part, i suggest this one, what you think?

Skylon by Climberfx, on Flickr

Skylon by Climberfx, on Flickr

Skylon by Climberfx, on Flickr

Skylon by Climberfx, on Flickr

Skylon by Climberfx, on Flickr

And Good Work Sir.

p.s: A Tip for the stabiliser. If flips entirely, not only the back. You can see it on about 40 seconds of this video.

Edited November 29, 2014 by Climberfx

[CaptainKipard]

I wasn't planning on it, but my texture source files are well organised and it'll be very simple to make it like this. I'll add it as an option. The black and white version will be default.

By the way. You didn't make those models did you?

Edited November 29, 2014 by Cpt. Kipard

[Climberfx]

No, i didn't. Is from the original team on Reaction Engines Website, but i have a 3D model from original CAD (simple one, the outside parts, not inside) and send today an email asking for the models and textures from this renderings, telling the purpose of use, and crossing my fingers to then sending me it.

I let you know if i get it!

[CaptainKipard]

That's great initiative! Thanks!

I hope you added a note about the benefits of popularising the Skylon.

Edited November 29, 2014 by Cpt. Kipard

[hieywiey]

Is it going to be called Skylon in the game, or are you going to make a unique name,like how Tantares does?

[Climberfx]

I love the name and logo of Skylon. And that way will be easy to people find the ship.

[CaptainKipard]

Yeah I'm not good with names, which explains my dumb forum name. It'll be the Skylon, but I have an idea for a Kerbalised logo.