The Ultimate SKYLON Challenge --- [open]

[SkyRex94]

Build a Craft as usable and practical as the SKYLON concept

This is the Ultimate Challenge for designing a somewhat realistic runway launching craft which can bring a payload into orbit for an affordable price and usable by everyone. But it should be believable that something like it could somehow work in the real world.

Target:

Design a Craft which will be as usable as the current Skylon-concept and have the same advantages. This andvantages are: Being able to operate from every big airport in the world, so every country will have the opportunity to join in space travel and being able to be maintenaced in any normal Aircraft Hangar. So no need to build a tall VAB or even to build a Spaceport, just using the next airport.

RULES:

- It has to have wheels of some kind, to be able to roll into any hangar without extra equipment needed.

- When landed it has to have a maximum height (including payload) of smaller then an upright standing Orange Tank, to be able to fit in any Aircraft Hangar.

- It has to be able to bring some kind of payload into an at least 75*75km Orbit

- It has to be able to return to the place where it launched

- No parts should crash onto Kerbin (although it is allowed to drop things, if they would burn up during reentry, proof with DRE)

- NO part clipping, not even possible clipping, especially no air-intake clipping, volume of craft has to be the sum of the volume of all parts.

- Mod required: FAR or NEAR

- Parts allowed: only Stock, to make it fair

- Mods allowed: Any Visual, any functional/data, NO parts or reconfigs of stock parts/fuels etc. - ask if unsure

So it doesn't necessary have to be a SSTO or a Spaceplane, the rules don't forbid to do something else, but it has to be as practical and usable as a SSTO-Spaceplane would be, according to the rules.

Points:

( (Maximum payload in kg ) divided by (funds per ton payload) ) ---> higher number is better

You have to proof two different flights and your final points will be the middle value of the points of these two flights, so proofing reusability.

It's calculating max payload within because its just as important to bring as much stuff as possible in one go up there as it is to do this at reasonable price. You can't build anything big if your highly efficient Plane has a maximum load of 0.5 Tons of payload.

Example calculation:

craft cost with payload 100.000 Funds / Payload Cost 20000 Funds /Payload Weight 15 tons

Funds per ton: 1st flight 101 F/t , 2nd flight 99 F/t

Calculation:

1st flight: (15000 ) / 101 = 148,5

2nd flight: ( 15000 ) / 99 = 151,5

middle Value = 150 Points

How to Enter:

Submit a picture of your loaded craft next to an orange tank to proof the height limit.

Proof (pictures or video) the two needed flights for an entry, including clear pictures of: Craft cost with payload, payload weight and cost, final delivery orbit, start landing and flight, Recovered Funds after both flights showing the cost of the used fuel/(jettisoned parts)

Ranking FAR:

1. 298.6 points --- Cygnus Link
   
2. 89.44 points --- SkyRex94 Link
   
3. 55.78 points --- SanderB Link
   
4. ...
   

Ranking NEAR:

Let me know your opinion about the general idea, the formular for calculating points and the Name of the challenge itself if you can think of anything better. And of additional rules if you understood what i'm aiming for and you see a loophole in the current rules.

Request:

If someone here is good in designing graphics and is in search for a new little project: What about a Signature Emblem for all competitors of this challenge (like the ones from Jool-5 or K-Price), to enhance your signature. Everybody can feel free to post any Design for a Challenge-Emblem in this thread. The best and most cool-looking Design will be choosen for this Challenge and the Designer will be Mentioned here in the Main Post.

Cheers

SkyRex94

Edited October 24, 2014 by SkyRex94

[TJPrime]

Seems like a sound challenge. Only two comments:

- Why do we have to use FAR or NEAR? Surely we can choose to go stock aerodynamics if we want to.

- Don't worry about 0.25. For all we know, it could be released around Halloween - making the challenge a bore and sink down into the 'dead challenge' zone (basically what I call any challenge without entry/post beyond the page 5 mark)

[SkyRex94]

Seems like a sound challenge. Only two comments:

- Why do we have to use FAR or NEAR? Surely we can choose to go stock aerodynamics if we want to.

- Don't worry about 0.25. For all we know, it could be released around Halloween - making the challenge a bore and sink down into the 'dead challenge' zone (basically what I call any challenge without entry/post beyond the page 5 mark)

FAR/NEAR: because to fullfill the requirement of being believable, the shape of the craft should matter. And it wouldn't matter in stock.

Don't worry about 0.25, i will simply push it to the top as soon as it gets opened, but for now there aren't any cargo bays in stock and all the wing parts might get realigned with 0.25 and with this being mainly an atmospheric craft challenge i think it should start with the new plane parts with 0.25, no matter when it will be released.

[TJPrime]

Well couldn't you put a required mod as SP+ in the 0.24.2 stage, then get rid of that when 0.25 comes out?

[SkyRex94]

So 0.25 is out. The challenge is now opened!

I simplified the points again, since its about an lifter and not an interplanetary transfer craft (that could be payload).

Entries can be made right now.

I will make my own entry as soon as i find the time for it (ASAP)

[Kulebron]

( (Maximum payload in kg ) divided by (funds per ton payload) )

What? Does it mean that putting a more expensive payload will score you more points?

[Highlad]

How are you defining the payload? is it just the starting mass minus the end mass? So if you have an item in the cargo bay but you end up in orbit with fuel to spare, does the weight of fuel count towards your payload? I don't see why not because you could transfer the fuel to an orbital station and so it would be part of your payload.

[CaptainKipard]

Only stock. Damn...

[SkyRex94]

Clarifying the above questions:

funds per ton payload means how many funds you spent to bring up your payload per ton, but without the payload cost itself:

Example: 15t payload costing 1000 Funds. Ship with fuel and Payload cost 50000 Funds.

After delivering payload and recovered your craft you got 45000 Funds back. That means:

50000-45000-1000 = 4000 Funds to bring up the payload. 4000/15= 267

this example cost 267 F/t for payload delivery.

So payload cost gets subtracted, which means only the weight of the payload counts, regardless how expensive the equippment is.

And for what is payload:

Everything you leave in a stable orbit. That means if you can leave fuel somewhere in a stable orbit, it is also payload. But i think a pure fuel lifter will get a note that states 'fuel lifter only' because such a craft is not very flexible in terms of operation scenarios.

[SanderB]

This is my first completely successful attempt.

Payload mass was 1.165t (2 jr docking ports + 2 FL-T100 fuel tanks with fuel).

Fuel used: 1040-432 = 608.

Cost per t: 240.07$ (at 0.46$ per unit of fuel).

http://youtu.be/OXLgvgNTldQ

There's lots of space for optimization too, especially with a fuel planes because they can just offload whatever they don't need to get back to KSC in one piece. Cargo planes have to plan their payload fraction much more.

[SanderB]

Here is my second entry, slightly more optimized.

Payload mass: 4.607t (0.1t for docking ports, 4.5t and 0.5625t for the fuel tanks minus 0.555t for fuel used from the payload.)

Cost per t: 101.47$ (1016.29 units of fuel used from the recovered craft: 0.46$ * 1016.29 / 4.607t)

[ZodiaK]

you should have a seperate catagory for FAR/NEAR to make it fair

[SkyRex94]

Here is my second entry, slightly more optimized.

Payload mass: 4.607t (0.1t for docking ports, 4.5t and 0.5625t for the fuel tanks minus 0.555t for fuel used from the payload.)

Cost per t: 101.47$ (1016.29 units of fuel used from the recovered craft: 0.46$ * 1016.29 / 4.607t)

I'm sorry but i can't accept this as it is.

-Okay i can see its smaller than an orange tank.

-but the rules said you should make two flights to show reusability and mostly, how easy it is to fly, so if its easy to handle, the numbers from both flights shouldn't differ that much.

- you can't just say xxxx fuel * 0.46 = xxxx cost. I just looked in my KSP : LF costs 0.8 per unit, OX 0.18 per unit. and a plane uses different amounts of both. So the easiest way is to show the total cost of payload, the total cost of craft and then the recovery screen after landed back, because it tells you exactly how many funds you get back.

I've seen your craft is capable of doing what is asked here. so you can do a correct entry with that craft if you want, but you have to do two flights with the same craft, show the cost of payload and craft and show both recovery screens after the two flights.

[SanderB]

I don't have a career save with anything unlocked, do I have to have the recovery screen?

[SkyRex94]

I don't have a career save with anything unlocked, do I have to have the recovery screen?

you can create a career save, manipulate the science , so you unlock everything, copy your craft in and then you can get the recovery screen.

[SanderB]

have you or anyone else attempted this challenge? I'm having an extremely difficult time descending and landing in a plane of a similar configuration because I cant control its attitude well enough.

[ratchet freak]

have you or anyone else attempted this challenge? I'm having an extremely difficult time descending and landing in a plane of a similar configuration because I cant control its attitude well enough.

add more pitch control then, they are best places in front or at the back away from the COM

[SanderB]

Here comes entry #3 which is hopefully in the required format.

#3.1

#3.2

Entry #3.1

Payload: 5.1625t T800 (4.5t) + T100 (0.5625t), 2 clamp-o-tron docking ports (0.1t).

Cost per t: 88.91$ (

-

) / Payload

Points: 58.06 (5162.5 / 88.91)

Entry #3.2

Payload 5.1025t T800 (4.5t) + T100 (0.5625t), 2 clamp-o-tron docking ports (0.1t) minus 0.06t for 12 units of LFuel.

Cost per t: 93.48$ (

minus

) / 5.1025

Points: 54.48 (5,102.5 / 93.48)

Average points: 56.27

I hope I've dotted all the i's this time.

Nobody need watch the video files through to the end, they were comfortable and easy going flights a monkey could do with its hands tied behind its back, so just take my word for it . A few interviews were spliced in the footage because I was bored silly while flying the space-planes.

[sdj64]

I have an entry in progress, first flight complete with a 5.68 ton payload and a cost per ton of $75.05. Not bad but I might try again with a bigger plane. I'll post pictures when I'm finished with flight 2.

[Highlad]

Will be submitting my plane here tonight. Just reserving a spot

[MaverickSawyer]

I'll give this a swing. Few questions before I begin, though...

-Is Tweakscale acceptable or not allowed? (I plan on using it on the main gear and the RCS blocks only)

-Can I use MechJeb autopilots to help hold precise attitudes?

[SkyRex94]

Here's finally my own Entry for this Challenge:

Javascript is disabled. View full album

Craft: Skylon-X

Aero:FAR

Payload: 10.763 t , 8614 $

Craft with Payload: 40.676 t , 67166 $

Craft without Payload: 29.914 t , 58552 $

First flight Recovery: 57360 $

Second flight Recovery: 57134 $

1st flight: (58552-57360)/10.763 = 110,749 $/t

2nd flight: (58552-57134)/10.763 = 131,748 $/t

Points: ((10763/110,75)+(10763/131,75))/2 = 89,4377 Points

It can lift quite some tons but isn't as efficient as i hoped. But it looks kinda like the real Skylon concept and i thought that was a good representative for this challenge.

If someone wants to try it, i could share the craft file. But its not easy to fly, avoid stalling at any cost, because you wont be able to get it pointing in the right direction again. And it has Takeoff speed of Mach 0.5 when fully loaded.

Edited October 9, 2014 by SkyRex94

[SkyRex94]

Here comes entry #3 which is hopefully in the required format.

#3.1

#3.2

Entry #3.1

Payload: 5.1625t T800 (4.5t) + T100 (0.5625t), 2 clamp-o-tron docking ports (0.1t).

Cost per t: 88.91$ (

-

) / Payload

Points: 58.06 (5162.5 / 88.91)

Entry #3.2

Payload 5.1025t T800 (4.5t) + T100 (0.5625t), 2 clamp-o-tron docking ports (0.1t) minus 0.06t for 12 units of LFuel.

Cost per t: 93.48$ (

minus

) / 5.1025

Points: 54.48 (5,102.5 / 93.48)

Average points: 56.27

I hope I've dotted all the i's this time.

Nobody need watch the video files through to the end, they were comfortable and easy going flights a monkey could do with its hands tied behind its back, so just take my word for it . A few interviews were spliced in the footage because I was bored silly while flying the space-planes.

Yes now everything required is there. But you forgot to subtract the 12 units LF from the cost, since you recovered them at the end:

So 12*0.8 = 9.6

2nd flight cost = (21620-21143+9,6)/5.1025 = 95,365 $/t

Points: 5102,5/95,365 = 53,5

Making (53.5+58.06)/2 = 55.78 your final points.

But well done, very efficient design and craft.

[CaptainKipard]

What engine is that on the tail? Rocket or jet?

[SanderB]

Also I'd like to note that it feels like overkill to make the points linearly proportional to payload mass. I understand 500kg payloads should receive a penalty, but a 20t payload that is raised at 200$ per t surely should not receive more points vs a payload of 5t at 100$ per t, right? I think a formula like [Price / (payloadMass - 100kg)] is much fairer. It penalizes undersized launchers but not so much that a 5x bigger payload launched 3x less efficiently will outrank it by lightyears.

ps. the reason I didn't include the 12 units of fuel from the payload in the launch price was because it was payload. The decreased mass is its own penalty imo.

Edited October 9, 2014 by SanderB