The K Prize - 100% reusable spaceplane to orbit and back

[pinolallo]

The hard part of the job is not only create a new craft, but follow project goals.

I just need to replace the "fatbob" SSTO cargo for many reasons: was too much heavy (more thant 112 tons), too many engines means too many ram intakes and to too much fuel.

My latest experimental SSTOs drove me producing K-prized tools like "SpaceJar", and the "rondine".

What I discovered (and what I'm going to share with you) are the correct ratio to build an efficient SSTO (that is not law, but is what I discovered to be the better configuration):

1. You will need 1 turbojet with 8 intakes to lift 11 tons of weight (including the turbojet and airintakes of course).
   
2. You will need to reach at least 2150 m/s before 36.000 m to have a <100m/s DV for 100km apoapsis circularization maneuver,
   
3. To reach such a speed your will need at least 75 lt of jet fuel.
   
4. The best launching strategy is to reach as soon as possible 350m/s of ascensional speed (eg. with a step slope ascent curve), then level and speed up until the needed speed is reached in less than 5 mins.
   
5. If you don't need to transfer your ship around the Kerbol system, but just to reach orbit you can doit using small rocket and so less rocket fuel.
   
6. Smart strategy is to divide the jet fuel flows from the rocket fuel flow: an perfect SSTO will burnout all it's jet fuel just before reach space and before engage rockets.
   
7. SSTO need to be tested in any fuel condition, because also the reenter and/or re approach the runaway can be hard without a balanced plane: so the wing design and the weight displacement is one of the main goal. When you are designing a SSTO find a balance center without fuel tanks an then place them without moving that center.
   

Using that advices I produced a brand new SSTO cargo: the Sparrow.

• weights less than 40 tons without the 20ton payload
  
• is a STOL plane that will fly at 20m/s: landing almost anywhere was never so easy
  
• just 6 engines for 60tons
  
• fast (2200 m/s at 34.000 m(with payload)
  
• Very good flight maneuvers performance
  
• Full SS (docking and balanced RCS)
  

Special made wings *yes another gate crasher* using the procedural wings by DJY is probably one of my best spaceplanes. I'm extensively using it to build a new (large) SpaceStation around kerbin.

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[xtremespino]

Heres another SSTO Spaceplane, called the Sparrow (I know somebody else already used that name just above this post, but I had already made the video before I saw it, so sorry pinolallo )

Enjoy

-Xtremespino

[pinolallo]

Np xtremespino , Sparrow It was a temp name, the ship is not pubblished yet, I'm going to use italian names, and I'm thinking to call it "Gabbiano"(seagul). The cargo is working hard shuttling the component for my new Kerbin SpaceStation and is almost perfect. Right now Steve Kerman is returning from the STS-04 (linking the fuel tank module). Are planned 12 STS missions to complete the spacestation project.

I'm currently using the death Reenter mod (g force and temperature) and il Gabbiano is working fine.

Edited December 5, 2013 by pinolallo

[xtremespino]

Ok, thats good.

Edited December 6, 2013 by xtremespino

[KnifeEdge]

my entry

https://dl.dropboxusercontent.com/u/93272389/Unpowered%20Kerbin%20Escape.craft

are infinigliders allowed ? this thing can break kerbin escape unpowered

[El wonso]

How about adding docking to kudos (when .23 is released ofc)?

[boolybooly]

Pinolallo, thanks for your experimental conclusions, I added your report as a gatecrasher, hope you approve!

xtremespino, thanks for another thoughtful and well narrated video of your mission. Shame you missed the 1st Class Advanced Pilot Precision Award but you did pretty well to get down intact on that rough terrain. Well played!

Knife edge, thanks for your craft file, yes infinigliders are in, its your call. Anything which the game permits on stock settings is allowed. Are you claiming a completed mission ?

El wonso, ah! actually its already included but there was a roll back and it got lost. Advanced Pilot Precision Award in its own right and 1st Class if you get both docking and a runway landing.

Edited December 7, 2013 by boolybooly

[El wonso]

Same as before but with docking.

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Edited December 8, 2013 by El wonso

[Spartwo]

Some time in the latter half of one of my 12pm-7am playing sessions(I never remember what I did,they give birth to some beautys though)from a couple days ago,Tired me thought it was a good idea to convert the 'Arrow' which was made for the Machingbird challenge(2263m/s).

Into a SSTO,It was I resumed the game today and found this in a 267x280 orbit around kerbin.

I returned and found there was no .craft:/,typical.

[boolybooly]

Thanks for your mission report El wonso, the highly regarded Advanced Pilot Precision Award 1st Class is yours. I have given your report its own link so people dont miss the additional screenshots from the first mission.

Spartwo thanks for your screenshots, the Arrow looks very suitable for spaceplane duty. Congratulations on your Advanced Pilot Precision Award and welcome to the K Prize party.

[bsalis]

I am back once again for a .22 K-prize. I am *finally* submitting the Boxkite, of which the original was built a few versions ago. I think it might even genuinely be a novel style of SSTO that is my own creation. Note that this craft has a 16:5 intake:engine ratio. Sorry for the many pics - this was a long flight.

Bill prepares for flight.

Ballistic! (has a little more TWR than needed really)

In orbit. Tis a long one this craft.

I'll skip the Pe pic, because.... where are we?

It's Duna! In a questionably safe landing configuration.

Yowsers. Bill needs clean underwear now. Good thing he packed them.

We have arrived. Bill is happy.

(I must admit to some F9 abuse... quite a few attempts to land in one piece - sure you can see why. I did nail this first time many months ago, before the Duna "art" pass when there was those low flat plains)

Back at Kerbin. I overshot.

Gliding in on a long final.

Victory.

[leafty]

My entry for the Better Aeris 4A challenge, the Aeris 4A - Aerospike Edition:

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[boolybooly]

Hi again bsalis, welcome back and thanks for your mission report. What an unusual design with the elongated fuselage, forward nukes and assymetrical aerospike, I would guess that can add a bit of thrust, but can the reaction wheels compensate for the torque at that small angle or do you have to make short burns? Is the engine slightly angled as well, doesnt look it? Anyway congratulaitons on your Expeditionary Astrokerbal Distinction and Advanced Pilot Precision Award.

leafty thanks for your mission report and welcome to the K Prize. Congratulations on completing the mission successfully, with a precision orbital docking and landing earning you a deserved Advance Pilot Precision 1st Class.

Edited December 10, 2013 by boolybooly

[bsalis]

What an unusual design with the elongated fuselage, forward nukes and assymetrical aerospike

There are two aerospikes, so they are balanced. The second is on the underside, up the front. You can see it in the last pic at the bottom left corner. The Kerbin re-entry pic has a good view of it too.

There are a lot of unusual aspects to this design that make it work. It the sort of design that fits together like a jigsaw puzzle.

[Rosarium]

hello all!

here my tiny SPIRITO:

49 parts- up to 1300d/v once refueled in orbit, enough to another refuel at minmus at least. Try it! SPIRITO ASAAAA concession.

report:

ok take off....

once in orbit

station intercepted!

cool IVA docking vision!

all done without causalities

the reentry is my speciality! just right above the KSC!

my cousin lives there

K prize!

P.S.

the craft have a ridiculous electricity charge, i often have to EVA to place the craft's panel to the sun light, fun but can be avoided by just adding a battery.

Edited December 10, 2013 by Rosarium

[that1guy]

Going bigger than before... Fairly confident that this craft could get out to Duna and back, have not tried it though. However, I return to the K-prize thread to claim a prize for the Pices VI

[boolybooly]

Thanks Rosarium for you screenies, welcome back and congratulations on successfully completing your K Prize mission with Advanced Pilot Precision Award for docking in orbit.

Hope you made class OK that1guy! Thanks for your video report and congratulations on acquiring the Advanced Pilot Precision Award 1st Class for docking and landing on the runway. I think you are right, the electric charge transfer is unavoidable on a station with power generators. Its might be open to abuse but I am inclined to discount charge entirely from the K Prize rules on fuel transfer except in a case where it contributes to ion propulsion where it acts as fuel, which will have to be judged case by case. Pernickety attitude control related electricity transfer rules are not going to add to the enjoyment of the K-Prize especially when you can use Timewarp to reduce the amount of control you need already by stopping rotation. So yes you are right it is perfectly acceptable, in this case.

[Mecha Pants]

I present my first and last SSTO of .22, it has a relatively reasonable intake to jet ratio, but aside from it's two man crew, it doesn't really offer anything in terms of cargo capacity as of yet.

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Edited June 27, 2014 by Mecha Pants

[Rhomphaia]

Thought I would give the new R.A.P.I.E.Rs a go. The test flight of the Phoenixhammer Mk0.23

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Pretty easy to build an SSTO with these I think.

Edited December 17, 2013 by Rhomphaia

[boolybooly]

Thanks Mecha Pants for what is probably the last V0.22 entry. Congratulations on a classic K-Prize winning orbit and successful bush landing with Dodo SSTO. Welcome to the guest list for the K-Prize party.

Thanks also to Rhomphaia for your Imgur record of the first rapier attempt. Bad luck on your attempted bush landing crash, the rear wheels look like they might be a little close together for rough terrain. For future reference it is OK to reload from a save. Your attempt earns a link as a gatecrasher with suitable quip.

I will be trying out the rapier tomorrow. I think the space plane builders have a special toy in that and a special thankyou is due to HarvesteR and Co. for such a nice Christmas present. So thanks Squad, have a merry Christmas y Feliz Navidad!

[Spartwo]

I have an SSTO which puts my last entry to shame it's from .22 which list would I go on?

[whistlehead]

Ladies and gentlemen, I have made it... to SPACE!

I decided as one final fling in 0.22 to achieve the first thing I tried to do in the game - take a spaceplane into space. Meet the Soothsayer.

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Two basics, six turbos, three LV-45s, eight 24-77s and one LV-N for long distance travel (untouched during ascent). I haven't tried it out for range yet but I'm hopeful of the Mun at least. Started out with an orange tank and no clue of where I was going, and a conviction it wouldn't work. A few hours later, SPACE.

Full mission report whenever I repeat it with a finger over the F1 key! (And when I can pluck up the courage to deorbit the thing)

Regards,

Chris

Edited December 17, 2013 by whistlehead

[Rhomphaia]

Thanks also to Rhomphaia for your Imgur record of the first rapier attempt. Bad luck on your attempted bush landing crash, the rear wheels look like they might be a little close together for rough terrain. For future reference it is OK to reload from a save. Your attempt earns a link as a gatecrasher with suitable quip.

I will be trying out the rapier tomorrow. I think the space plane builders have a special toy in that and a special thankyou is due to HarvesteR and Co. for such a nice Christmas present. So thanks Squad, have a merry Christmas y Feliz Navidad!

They were, I knew it was going to be a problem before I started, but the main reason for the attempt was to compare the rapier to the original turbojet/twin 909 version of that plane.

The rapier is not as efficient in this case, but I think that it will certainly come into its own using two to replace an aerospike/twin turbojet combo. No need to worry about asymmetric flame-out.

[Eric S]

I will be trying out the rapier tomorrow. I think the space plane builders have a special toy in that and a special thankyou is due to HarvesteR and Co. for such a nice Christmas present. So thanks Squad, have a merry Christmas y Feliz Navidad!

The RAPIER is a matter of convenience, you only need to find a place to put a single engine. The WOW factor that people are seeing (and in some cases mistaking for the RAPIER being OP) is because of changes to intakes, jet engines, resource handling, etc. Without extreme levels of intake spamming, I just put a spaceplane into a 112 km orbit on all of 60 delta-v from the rockets, the rest came from an old fashioned turbojet. Among other things, I'm not sure if turbojets still lose thrust at some point, but at 2300 m/s and an altitude of about 30km, I was both climbing and accelerating, and I don't think any amount of intake spamming would have managed that in 0.22.

[Rhomphaia]

The RAPIER is a matter of convenience, you only need to find a place to put a single engine. The WOW factor that people are seeing (and in some cases mistaking for the RAPIER being OP) is because of changes to intakes, jet engines, resource handling, etc. Without extreme levels of intake spamming, I just put a spaceplane into a 112 km orbit on all of 60 delta-v from the rockets, the rest came from an old fashioned turbojet. Among other things, I'm not sure if turbojets still lose thrust at some point, but at 2300 m/s and an altitude of about 30km, I was both climbing and accelerating, and I don't think any amount of intake spamming would have managed that in 0.22.

I just took the original Aeris 4A out for a spin, managed to get it 34km @ 1600m/s on jets, at full throttle all the way. So a serious change. the thrust on the turbo jets starts to drop around 22km where usually it would flame-out. Felt like flying with mechjebs prevent flame-out on.