Twenty Ton Speed Run

[Ultimate Steve]

Welcome to the Twenty Ton Speed Run!

Your goal is to take a craft that masses no more than 20 tons (including EVA Kerbals and not including any launch clamps) and reach the highest velocity possible, relative to Kerbin.

 

Fairly simple, so I think I can get away with not submitting something as it's fairly obvious that this challenge is possible.

 

Rules:

• 20 ton limit includes EVA Kerbals and not launch clamps. Don't abuse the launch clamps.
• Velocity is measured using the "orbital" setting on the navball.
• You may not leave Kerbin's SOI for the challenge. You may be on an escape trajectory at the end, but you can't measure your velocity outside Kerbin's SOI or leave before measurement.
• Accidental Mun/Minmus encounters are alright, but try to avoid them.
• Stock and Making History only, although non physics changing mods may be installed, and other parts mods may be installed but not used.
• In general try to not exploit stuff. No debug menu, .sfs editing, HyperEdit, Kraken drives, etc.
• Proof required is a screenshot at or near your highest velocity. Other screenshots showing your vehicle and how it works are required, unless you have a video.
• There will be separate leaderboards for manned and unmanned entries.

Leaderboards:

Manned:

1. @Aeroboi, 33,718.2m/s with an ion/rapier hybrid, probably approaching the limit of what can be done with this challenge.
2. @dnbattley, 15,893m/s in the 20T flyer, using the EVA jetpack at the end.
3. @Magzimum, 6856.9m/s, EVA seat, using a three stage liquid fueled design.
4. @Andetch, 3322.3m/s with a capsule!

Unmanned:

1. @GRS, 21,109.2m/s in the "Something Mk2," like the Something but improved.
2. @GRS, 17,772.2m/s in the "Something," a three Rapier, terrier, ion ship.
3. @Ultimate Steve, 12929.1m/s, unmanned, five staged Rapier, LF, and ion hybrid.

Have fun!

Edited February 28, 2019 by Ultimate Steve

[Aeroboi]

@Ultimate Steve Working on a craft right now.

Is it ok to travel to the edge of the SOI and then do a ION speedrun with a gravity assist to the other edge of the SOI or does it need to be a direct trans solar ejection?

[Ultimate Steve]

4 hours ago, Aeroboi said:

@Ultimate Steve Working on a craft right now.

Is it ok to travel to the edge of the SOI and then do a ION speedrun with a gravity assist to the other edge of the SOI or does it need to be a direct trans solar ejection?

That's fine, as long as you do not leave Kerbin's SOI before you measure your velocity.

[Andetch]

Seems to me that most dV into LKO under 20T launch weight wins this. Right?

I just did a test flight in a little contraption and broke exit velocity. Had I just made an extreme transfer orbit, with the pp as close to Kerbin's atmosphere and waited until I approached the pp before burning off my remaining fuel probably could have got higher. The issue I think people are probably facing is how to get a tank, a kerbal and an engine into LKO for the least effort! 

[Andetch]

19.971 T at launch

3322.3 m/s at fastest by Navball, at around 9 mins 25 secs

Remember, the lower your periapsis then the higher your speed boost from gravity.

If I played with the flightpathI could probably get a bit faster.

Took me very little time to build the craft, very simple design. 

 

Edited February 25, 2019 by Andetch

[Magzimum]

I managed to get 6856.9 m/s. Compliments on a fun challenge!

I could probably optimize another 100 m/s out of this, but for now I would like to enter this. More info in the spoiler.

Spoiler

The general idea was to get into orbit, into whatever apoapsis, but a periapsis around 70 km. Then on a 2nd pass, increase the apoapsis to something beyond Minmus. And on a final pass of the Periapsis, use all the dV the rocket had left (which was around 3000 m/s).

Picture showing craft mass. (I created a tiny stage, which isn't very aerodynamic, to get close to the 20 tons, giving it 43 m/s extra).

Launch. Craft has no fins, and three engines. Makes for a little awkward flight.

Jeb coasting to the Apoapsis before circularizing.

Apoapsis at max. without leaving Kerbin SoI.

Pointless picture.

Final stage.

And maximum speed as recorded by me on this attempt.

If max. speed had been closer to the Pe, it would have been higher.

 

Good thing there's no snacks on board. Jeb would not like to be awake at the destination.

 

 

 

[Aeroboi]

Made a very optimized ION craft to do a speedrun from one side of the SOI to the other.

It weighs 9 Ton and should be able to get it to the highest SMA using a TSTO or super efficient SSTO. It has a constant TWR of 0.29 through 0.40 and runs continuously until empty right at the SOI border.

I won't give up final speed yet, I first make the entire vessel to get it there first

Edited February 26, 2019 by Aeroboi

[Ultimate Steve]

6 minutes ago, Aeroboi said:

Made a very optimized ION craft to do a speedrun from one side of the SOI to the other.

It weighs 9 Ton and should be able to get it to the highest SMA using a TSTO or super efficient SSTO. It has a constant TWR of 0.29 through 0.40 and runs continuously until empty right at the SOI border.

I won't give up final speed yet, I first make the entire vessel to get it there first

I tried an ion ship too, but it was very small... I might as well get on the leaderboard before you steal it!

 

My submission:

12929.1m/s.

 

 

In depth:

Spoiler

This is a five stage system, with a mass of 18.721 tons including the launch clamp. I could have gone up to 20 but the Rapiers don't have enough thrust and three of them would be very overkill.

Also it's unmanned.

A very slow takeoff. Also I have a reflection mod installed but the textures for the 1.6 retextured parts aren't in yet, so it looks weird.

Pitch over. I could use landing gear, I guess, to solve the TWR problem and maybe get away with one RAPIER.

Velocities of ~1500m/s are achieved. Some fuel is left in the tanks.

The second stage is an aerospike. Care must be taken not to flip because of the canards, and the lack of gimbal. This stage gets us to an apoapsis at the edge of Kerbin's SOI. Days later, we come around the other side and burn everything. The last ~200m/s in the aerospike stage is burned.

Then comes an LV-909 stage.

Then a spark stage.

Then an ion stage. I goofed here. I wanted to half my burn time so I added a second ion engine, but I forgot to add enough solar panels to run it, so it was basically dead weight. Also, ion engines can thrust through each other for some reason. I also had to burn off prograde by a few degrees to allow the sun to hit all of the solar panels. A few goofs. I could have gotten a few more km/s out of this if I had fixed those.

Accidental Mun flyby.

Final velocity - 12929.1m/s.

Then it fell into the sun.

 

 

 

 

 

[GRS]

I'll see if i can do it, a speed run away from Kerbol.

[GRS]

Shattered @Magzimum's record, only one more to break... (used a bigger Ion ship for final acceleration)

Edited February 26, 2019 by GRS

[GRS]

BEHOLD !!! THE...Something ??? (Mass : around 17 tons and has 3 Engine stages)

Terrier Orbital Stage, strategy : burn to Kerbin SOI edge, then start a 3 Hour-ish burn from Mun's Orbit altitude, with Radial In + Prograde burns to keep Pe around 70 Km.

Periapsis Shot.

Final Velocity : Just say 17772.2 m/s

Close up view.

Literally crashed Kerbol, will even escape Kerbol if this didn't happen.

Delta v amount : over 20 Km/s

(I think there's a little too many 17s, Mass of this thing 17 tons, Final velocity like 17 Km/s, and I'm 17 years old, i'll see what i can get in 19 tons of this thing)

Edited February 27, 2019 by GRS

[Aeroboi]

Finally made the entire vessel. This is a 1 rapier TSTO carrying the ION orbiter to at least -70/75km Suborbital flight. It then has a small drop stage to travel to the outer edge of the SMA to do a continuous speedrun.

I'm going to do the mission tomorrow.

Edited February 26, 2019 by Aeroboi

[GRS]

Outdid myself...

Even Lighter now...

Removing Shock Cone Intake.

Terrier Stage.

Getting to SOI Edge with 2 Ion Power. (Which are clipped)

We'll be burning from SOI Edge.

Removing Extra Tank.

Periapsis Shot.

And here...we have...21109.2 m/s Max Speed.

[dnbattley]

Well darn. I finally sat down today to have a go at this, only to find I'm 24 hours too late. Oh well, here is the mission report for posterity, plus as far as I can tell this is the current best "manned" report...

Spoiler

The hastily put together monstrosity weighed a svelte 16T - so already room to optimise there. Sparks were deployed to accelerate the rapiers ASAP in order to follow a naive "upward" trajectory straight away from Kerbin. The second (2 part) spark stage would continue this forward , increasing the Ap past the Mun, and the ions would be used thereafter.

As with others, the goal was simply to get to the edge of Kerbin SOI, and then begin the speed run. Lots of staging.

At the beginning of the final stage, Jeb was clearly delighted to be on board. At this stage he didn't appreciate he would already be leaving Kerbol's SOI...

Top speed in craft, 15,262m/s, but Jeb looked carefully at the rules, and decided he wasn't yet done...

15,893m/s after using all of his jetpack fuel...

Escape trajectory...

 

[GRS]

@Ultimate Steve, i think you should make separate entries, we're starting to get loads of entries.

[Aeroboi]

Finally made the entire mission.

I made a 6 stage 9.5 Ton ION upperstage. The staging only achieves marginal better Dv. However it also means I have more TWR for the amount of Dawn ION engines. So in reality I have more thrust to achieve more speed in the amount of travel time I have.

This means you can get quite a bit faster especially as you accelerate over a larger distance. The solar panels are also arranged in such a way that they catch 100% sunlight but that each stage has just above the required EC gain to achieve the least dry mass on every stage.

The only problem is that you have to manually allow fuel flow on each and every tank on the next stage which is a bit of a hassle.
The vehicle can withstand 30x physical timewarp using better timewarp mod. That means the entire trip only costed a half an hour from the runway up to SOI escape, but several re-attempts where made because of solar panel and fairing collisions I had to avoid.

Result:

After the run I achieved a whopping 33.718,2m/s Kerbin escape velocity and a Solar escape velocity of 42.943m/s.
It took 19 Days to get to Duna orbit.
39 days to get to Dres Orbit and 77 Days to get to Jool/Eeloo orbit.

Quite a few pictures so I spoilered them...

 

Spoiler

 

2: Silan Kerman tugged into the orbiter shelled into the fairing.

3: Very Smooth Takeoff

4: 450m/s at 1:38 mission clock

5: Best is to speed up to 500m/s while staying below 200m then raise nose slowly all the way to 6.4° pitch. Then stay on 6.4° for the remainder of the flight. In the next picture we already go 900m/s while under 4500m.

 

6: What was that?

7: Aha (as expected)

8: Final speed 1612m/s before switching to closed cycle.

9: Burning to reach orbit. (What did I lose?)

10: Almost reached orbit...

11: Not the cleanest of fairing deployment

12: Orbiter in full deployment.

13: Starting the burn to get to the highest SMA. I will fire my trajectory radially out relative to the Sun so that by the time I get there I can follow the same orbital trajectory as Kerbin is relative to the Sun. This way I make sure I can get 100% effect from the static solar panels when doing the burn.

14: Silan Kerman's position.

15: Finishing the first lap of the burn, one more to go.

16: 2nd and last burn.

17: A better view of the staging mechanism underneath while leaving Kerbin.

18: Achieved the highest SMA possible and thrust cancelled the orbital velocity to 0, 1 second before leaving the SOI.

19: Emptying the last of the remainder of the drop tank required to get to this point while pointing straight at kerbin.

20: Staging the droptank.

21: Jettisoning the 2nd set of droptanks. I had to stop the engines otherwise they would break the gigantor solar panels. As you can see It drops the engines and the required solar panels with it.

22: Other side.

23: ByeBye..

24:Staging away the last stage with 2 gigantors and 5 dawn engines.

25: Kerbin Getting closer...

26: We only travel 360m/s faster then on the 2nd picture while zipping away from our Periapsis just above the atmosphere...

27: 25.000m/s!

28: The last stage is a drop tank mounted on the front. It is actually attached to the docking port jr where the chair and silan sits at and acts as the command from here part, the xenon tanks are attached to it but rotated and dragged it to the front for a very lightweight front mounted decoupling solution.

29: Bye...

30: 31.409 and quite some Dv and distance yet to go...

31: Almost...

32: Final speed 33718.2m/s!!!!

Speed after SOI change, 43.065.7m/s

 

 

Edited February 28, 2019 by Aeroboi