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

[camacju]

@boolybooly I see my Advanced Pilot Precision Award x5 and raise myself Advanced Pilot Precision Award x8.

In VAB, first lap

Spoiler

Craft in VAB. This is about the most mass per Rapier engine that can safely take off from the runway, and I don't like flats takeoffs. I got a similar payload fraction adding another pair of wing strakes to increase lift but that's also extra mass.

On runway

I accelerate at sea level until the wing incidence starts making me climb.

I turn on the nuclear engine at 1660-1680 m/s. This is high enough that the Rapier's higher specific impulse saves lots of delta-v but not so high that the Rapier's effective Isp drops below the Nerv.

In orbit

Aerobraking

Approach

First lap complete

Second through fourth laps

Spoiler

Ascent is easier because of less mass this time

I turn on the nuclear engine too late here so I lose too much delta-v to drag

In orbit

Lap 2 complete

Lap 3 ascent

Nuke turns on at 1680 m/s

In orbit

Approach

Lap 3 complete. I don't know what went wrong with the fuel gauge here but you can see I have lots of delta-v remaining

Ascent, nuke turns on at 1670 m/s

In orbit

Approach

Lap 4 complete

Laps 5-8

Spoiler

At this point the wing area on this craft starts to be a bit excessive. I end up climbing a bit too quickly to be fully efficient.

In orbit

Lap 5 complete

Nuke turns on at 1680 m/s as usual

In orbit

Lap 6 complete. I was initially only going for seven laps but at this point I realized I actually had enough fuel for an eighth.

I took as shallow of an ascent as I could here to save fuel for the last lap because the wing area was going to start really being excessive.

In orbit

Lap 7 complete.

Final ascent. At this point I can't climb efficiently anymore but I try my best

In orbit - 53 m/s left

Deorbiting - 13 m/s left!

Final approach

Eight orbits complete

 

I had 40-50 m/s of deorbit burn for each of my eight orbits for about 360 m/s wasted. I probably wasted another 200-250 m/s on orbital insertions. Maybe with a bit more fuel and better flight profiles I can fit in a ninth orbit but I probably won't attempt it.

 

Edit: Instead of "Untitled Space Craft" can you call it "Relay Race 2"

Edited April 18, 2021 by camacju

[tosha]

Overall experience with youtube and the forums recently indicates that part clipping is now a fully accepted strategy. 

Interesting. I'll just say that the kerbals have found a way to hyperdensify fuel. After all, their planets are REALLY dense. 

[camacju]

The craft would probably work fine even without clipping of the fuel tanks. I only did that so I could have a lighter fairing

[boolybooly]

Congratulations @camacju on completing the K-Prize mission eight times over in one launch with a prodigious feat of endurance demonstrating true dedication to the cause of reusability!

APPA x8 it is, well flown, thanks for your mission report and welcome back to the K-Prize roll of honour aka the K-Prize party guest list.

 

[tosha]

 

This should be 4 APPAs on 

SRSTO

Jack of No Trades

Mk2 SSTO for Passengers

Silver Bullet

[boolybooly]

It liiives!

@toshathanks for resurrecting the K-Prize.

Congratulations on completing the K-Prize challenge successfully four times with four craft designs and earning three highly regarded APPAs with SRSTO, Jack of No Trades & Mk2 SSTO for Passengers and a sincerely respectable PPM for the Silver Bullet mission which I hope you agree did not touch the grey runway texture due to collision with the floodlight and came to rest, with zero dV or any other motive means, on the sloping green bank around the runway which counts as KSC field ... so close.

Thanks for your video mission reports and welcome back to the K-Prize party guest list aka the roll of honour.   (I have added the mission kudos beneath your previous successful mission listings.)

[tosha]

Thanks! I concur on the silver bullet demotion to PPM. Stupid light

[camacju]

Rocket-only SSTO craft are pretty fun. I think I did a rocket-only SSTO to Eeloo once, but it was vertical takeoff. I wonder how far I can push a horizontal takeoff craft?

[OJT]

Here's my entry with a relatively simple design

2 RAPIERs and one NERVA engine. It has a probe core so it can be flown autonomously. Fuel tanks aren't filled up completely so you can balance the weight around if needed. And it also has a cargo bay, which is somewhat small but sizeable enough to fit, for example, this Minmus lander

Next set of pictures show the craft getting to orbit, deploying the payload and returning back to KSC autonomously, while the pilot in the lander continues all the way to Minmus and lands here. Pilot also returned back to Kerbin in the same lander successfully, but I forgot to take pictures 

Spoiler

Here's the craft file if anyone is interested

[boolybooly]

Congratulations @OJT on successfully completing the K-Prize challenge mission with the effective Concorde SSTO, lifting a compact Minmus lander into Kerbin orbit and returning to land safely on the KSC runway which earns the highly regarded kudos of an Advanced Pilot Precision Award along with the much sought after Utilitarial Commendation for the payload to orbit. Thankyou for your mission report and welcome to the K-Prize party guest list aka the roll of honour.  

[Staticalliam7]

In theory, if I flew an ssto, landed, refueled it, reloaded it, and then flew it again, would I get a special rank for true reusability?

[boolybooly]

2 hours ago, Staticalliam7 said:

In theory, if I flew an ssto, landed, refueled it, reloaded it, and then flew it again, would I get a special rank for true reusability?

You get a x2 or xn multiplier by the kudos, refuelling on Kerbin ends one mission and starts another but they are added together if it is the same craft. There have been precedents and I discussed it a bit after this post...

 

[camacju]

13 hours ago, Staticalliam7 said:

In theory, if I flew an ssto, landed, refueled it, reloaded it, and then flew it again, would I get a special rank for true reusability?

Just don't refuel it. Do the missions in succession without refueling lol

I've got a design that should be able to do a Laythe mission, land back on Kerbin, then do a Mun mission, land on Kerbin, and then an Eeloo mission, before coming back to Kerbin, but I don't have the patience to fly it right now.

[boolybooly]

15 hours ago, Staticalliam7 said:

In theory, if I flew an ssto, landed, refueled it, reloaded it, and then flew it again, would I get a special rank for true reusability?

Plus I forgot to mention that if you examine the OP you will see Dman Revolution was awarded a discretionary HyperCycle award for extraordinary services to reusability for x12  K-Prize mission flights with the same craft launch. So I would say that if you or anyone achieves the same or better then you will also earn a HyperCycle award, which is a very rare award since only one has ever been awarded to the best of my knowledge.

 

[Staticalliam7]

4 hours ago, camacju said:

Just don't refuel it. Do the missions in succession without refueling lol

I meant refuelling on kerbin, which to my knowledge is well within the rules

[camacju]

As far as I'm aware this is the lightest ever Moho SSTO.

Previous record was 14.9 tons by N727.

[boolybooly]

Congratulations @camacjuon completing the K-Prize mission with the diminutive 13.6 ton Moho SSTO. If you have a name for that let me know and I will add it. Landing involved contact with the runway but the craft stopped on the green bank beside it, which by Kerbal standards is close enough to get to the SPH snack bar and earns the well respected kudos of a Pilot Proficiency Medal.

Landing on Moho and returning to tell the tale of prodigious use of gravity assists to great grand nieces and nephews earns a laudable Astrokerbal Distinction (Moho). While there is no official kudos for ship size relating to a specific destination the commitee recognise it was a smaller ship than the last one which made it to Moho (which is a hard place to get to) and back and would like to say it was a commendable feat of distinction which must have required great patience and planning.

Thanks for your video mission report and welcome back to the K-Prize party guest list aka the roll of honour.

PS The K-Prize committee unanimously voted to award a discretionary  Slingshot Supremo for this mission for its use of multiple slingshots to reach its target  and make a landing on the innermost planet of the Kerbol system and return. Only one other Slingshot Supremo has been awarded, to dvader for a remarkable 2340 year Altitudinalist Record attempt, which seems an appropriate symmetry, for now.

Edited November 28, 2021 by boolybooly

[Admiral Fluffy]

Neat.

I have a Minmus capable SSTO, but can’t get back without a refuel.

[AtomicTech]

10 hours ago, Admiral Fluffy said:

Neat.

I have a Minmus capable SSTO, but can’t get back without a refuel.

Add some Xenon!

[Admiral Fluffy]

53 minutes ago, AtomicTech said:

Add some Xenon!

Has NERVs, and that gets it most of the way there. Has enough Δ-V to land, but not enough to get back. 

(IDK if it has enough to get back, because i landed at a refueling base.)

[BuranAce]

neat! might try it out 

Edited December 1, 2021 by BuranAce

[camacju]

If you thought the last SSTO mission had a lot of gravity assists...

The 'Laythe Star' has enough range to go from Kerbin's surface, to Laythe's surface, and back to Kerbin ... three times in  a row without refueling.

To do so, however, requires many, many gravity assists.

[boolybooly]

Congratulations @camacju on completing the K-Prize mission with the prodigious use of slinghsot maneuvers to achieve three landings on Laythe and return to KSC runway from just one launch with a stylish interplanetary spaceship that looks like a star. For which the K-Prize commitee decided to make the uncommonly rare and prestigious discretionary Stelicious award, for spaceships shaped like a star as well as a Slingshot Supremo award for using a dozen or more slingshots in a single mission. 

- Advanced Pilot Precision Award x3, Astrokerbal Distinction (Laythe) x3 with Laythe Star (video). (Discretionary Slingshot Supremo award.) (Discretionary Stelicious award.)

Thanks for your video mission report and welcome back to the K-Prize party guest list aka the roll of honour.

[NyetiArts]

As a newish player I submit my first SSTO, Gazelle.  It's nothing exceptional, but it'll take a crew of three to LKO, dock, and fly back using two Whiplashes and a NERV.

(Link includes shots of orbital burn and docking.)

 

[boolybooly]

Hi @NyetiArts thanks for posting your career SSTO spaceplane Gazelle.

FYI if you would like to join the merry throng on the roll of honour aka K-Prize party guest list, then you need to share a report of an actual mission. Details are on page 1 of this thread. See para 1.