The Double Mission Challenge (Now with reduced repetition!)

[Vaporo]

The challenge is very simple: in one launch, take off from Kerbin, perform a mission that involves landing on another body, return to Kerbin, then, take of and complete the entire mission again. (With whatever you landed on Kerbin) You may, if you want, attempt to try this a third time. (Or a fourth. Or a fifth... Do it as many times as your heart desires, so long as it is in one launch.)

Scoring will be based off of the number of trips you took from Kerbin, minus one squared, multiplied by the multiplier of whatever celestial bodies you landed on listed in the table below, multiplied by 100, then added to the end mass, divided by the start mass, multiplied by 50,000 (this ratio will maximize at doubling the score) .

[TABLE=class: grid, width: 500, align: left]

[TR]

[TD]Body[/TD]

[TD]Multiplier[/TD]

[/TR]

[TR]

[TD]Mun[/TD]

[TD] 2.5[/TD]

[/TR]

[TR]

[TD]Minmus[/TD]

[TD] 2.3[/TD]

[/TR]

[TR]

[TD]Eve[/TD]

[TD] 11.0[/TD]

[/TR]

[TR]

[TD]Gilly[/TD]

[TD] 3.0[/TD]

[/TR]

[TR]

[TD]Duna[/TD]

[TD] 3.7[/TD]

[/TR]

[TR]

[TD]Ike[/TD]

[TD] 3.4[/TD]

[/TR]

[TR]

[TD]Moho[/TD]

[TD] 4.2[/TD]

[/TR]

[TR]

[TD]Eeloo[/TD]

[TD] 3.7[/TD]

[/TR]

[TR]

[TD]Dres[/TD]

[TD] 3.3[/TD]

[/TR]

[TR]

[TD]Pol[/TD]

[TD] 3.5[/TD]

[/TR]

[TR]

[TD]Bop[/TD]

[TD] 3.7[/TD]

[/TR]

[TR]

[TD]Tylo[/TD]

[TD] 5.5[/TD]

[/TR]

[TR]

[TD]Vall[/TD]

[TD] 4.5[/TD]

[/TR]

[TR]

[TD]Laythe[/TD]

[TD] 4.7[/TD]

[/TR]

[/TABLE]

These multipliers are loosely based off of the values in this delta-V map.

If you think they need adjusted, please say so.

So, the formula is:

(Mult*(Tr-1)^2*100)+((Em/Sm)*50000)

As I said, the End/Start ratio will maximize at doubling your score.

No Junk Left Behind: Leave no space junk anywhere (all debris hits a planet). +100 points

Junk hoarder: Do not drop any debris. At all. Ever. (All parts launched with are successfully returned to the surface of Kerbin at the end of the mission). +200

Grand Tour: Perform a grand tour on any launch. (Simply visit the SOI of every planet. No circularization above any planets required.) +200

Grander Tour: Perform a Grand Tour on EVERY launch. +200

Grandest Tour: Perform a grand tour on any launch AND circularize. (Visit the SOI of every celestial body AND circularize over every body.) +200

A Grand Day Out: Perform a Grandest Tour on EVERY launch. +200

Jool-5: Perform a Jool-5 mission. Twice. +700

Manning the Guns: All landers are manned. +100

Army: +50 for every Kerbal beyond the first one that are taken on the mission. (They must be on board at every launch and landing at Kerbin. Max +500 points.)

Leftovers: Have at least 2000 m/s of delta-v left over when the entire mission has been completed. (Does not apply to jet engines and ion engines). +100

Second Course: Have at least 5000 m/s of delta-v left over when the entire mission has been completed. (Does not apply to jet engines and ion engines). +100

Laziness: Have at least 10000 m/s of delta-v left over when the entire mission has been completed. (Does not apply to jet engines and ion engines). +100

Heavy: Your craft weighs more than ten tons at every point in the mission. (requires screenshots). +200

Eat More Chicken: Visit at least five Easter Eggs over the course of the mission. (No repetition of any required) +300

(All bonuses stack with all other bonuses.)

(Feel free to recommend new bonuses. I would like to add a few more.)

Rules:

1. You must launch from Kerbin, land on a celestial body (aside from Kerbin), return to Kerbin, and then complete the mission again (in the same ship).

1.5. This must be accomplished in one launch.

2. You may not send fuel ahead, use a mod to refuel your ship, etc. The fuel you use must be the fuel you launch with.

3. You may use a "mothership" to transport your lander(s) between bodies.

3.5. The mothership must land on Kerbin before redoing the mission.

3.6. Any parts left on the surface of a body may not be recovered after leaving the body (includes Kerbin).

3.7: The mothership must reunite with its lander before landing on Kerbin, and must land on Kerbin with the lander on board. (You can still drop the used up lander on Kerbin's surface, if you want).

4. You may not recover parts or fuel from previous launches of your lander. You may leave fuel or parts somewhere along your route, but may not recover it after landing on Kerbin. (You can complete subsequent launches ONLY with whatever you landed on Kerbin and nothing more.)

5. The final return ship must consist of at least one powered probe core, or at least one controlled command pod. (You must have control of the vessel when it lands).

6. You may land on multiple celestial bodies, provided, of course, that you return to those bodies in the same order on the next mission.

6.5 Multipliers stack additively.

7. No infinite fuel, no Hyperedit, no infinigliders etc. Try to keep it in the spirit of the challenge.

7.5. I will allow airhogging, but if you do choose to abuse air intakes I

WILL

put an asterisk next to your name on the scoreboard.

7.5.5. I will define airhogging as using stock aerodynamics and five or more air intakes per jet engine.

8. Screenshots of all the major points in the mission are required, (landings, dockings, etc.) as well as screenshots confirming the mass of the craft in the VAB / on the launchpad and at the end of the mission.

If you think the rules need modified / have mistakes /are confusing / have mistakes / are somehow exploitable / are just flat out too hard, please say so.

Balanced mods are allowed. (B9, NovaPunch, etc.)

FAR and NEAR are allowed.

Known forbidden mods:

Karborite

Kethane

Interstellar

Airships mods are allowed, but using them will cut the multiplier for the body it is used on in half. Airships used to ascend from Kerbin will cut all multipliers to 1/2.

Part Welder is allowed ONLY for reducing part counts. Do not use it for structural purposes.

If you have a mod you want to use but aren’t sure about, ask.

Because this challenge can get very boring very fast, I WILL NOT REQUIRE YOU TO ACTUALLY PERFORM ALL THE LAUNCHES (though it is preffered that you do). If your fuel usage and craft design (usually this only means if you refuel the same lander over and over again without dropping any tanks) *clearly* indicates that you can complete multiple launches, I will not require that you do the mission again, and I will (very conservatively) estimate how many launches can be performed. Doing this will also put you on a separate scoreboard. Also know that I will almost certainly ask for your .craft file to determine the final mass of your ship.

My entry:

Javascript is disabled. View full album

My final mass was 2.797 tons, and my start mass was 1110.166. I landed on the Mun twice, so:

(2.5*(2-1)^2)+((2.797/1110.166)*50000), which is 375.97.

I also got the Manned bonus, so +100.

Master Scoreboard:

1. ^Kulebron: 48,420- Jet rocket used to ascend from Kerbin. Small ion probe did all the landings. Went to Mun, Minmus, Duna, Ike, Dres, Pol, Bop, and Vall.

2. *gchristopher: 18,400- Seven launches from Kerbin to the Mun. Used an SSTO with a small LV-N powered lander. Used airhogging.

3. metaphor: 1200- Two launches from Kerbin to Eve. All stock. No dockings, no refuelings. Over 37000 m/s of delta-v. Quite impressive.

4. Lou:524.07-Two launches from Kerbin to Minmus. last stage was ion powered.

5. Vaporo: 475.97- Basic asparagus staged ship. Went to the Mun twice.

6.

7.

8.

9.

10.

* used airhogging, excessive part clipping, etc.

^ Only completed one launch, but shows that they could clearly complete more

Full Entry Scoreboard:

1. *gchristopher: 18,400- Seven launches from Kerbin to the Mun. Used an SSTO with a small LV-N powered lander. Used airhogging.

2. metaphor: 1200- Two launches from Kerbin to Eve. All stock. No dockings, no refuelings. Over 37000 m/s of delta-v. Quite impressive.

3. Lou:524.07-Two launches from Kerbin to Minmus. last stage was ion powered.

4. Vaporo: 475.97- Basic asparagus staged ship. Went to the Mun twice.

5.

6.

7.

8.

9.

10.

Partial Entry Scoreboard:

1. Kulebron: 48,420- Jet rocket used to ascend from Kerbin. Small ion probe did all the landings. Went to Mun, Minmus, Duna, Ike, Dres, Pol, Bop, and Vall.

2.

3.

4.

5.

6.

7.

8.

9.

10.

Edited November 8, 2014 by Vaporo

[cyberklad]

Is launching a big ship into LKO and then seperating a smaller lander. Then taking only the smaller lander over to the target bodie to land on it. And then docking back to the big ship for a landing and a new takeof before doing the same again legal ? I see that there is nothing against it in the rules. But would you allow it ?

It allso looks like you forgot some digits in your score calculations somewhere. http://www.wolframalpha.com/input/?i=%282.5*%282-1%29^2*100%29%2B%28%282.797%2F1110.166%29*50000%29 says your score is 375.9721519124167016464204452307132446859298519320534046259748...

Edited September 19, 2014 by cyberklad

[Vaporo]

Is launching a big ship into LKO and then seperating a smaller lander. Then taking only the smaller lander over to the target bodie to land on it. And then docking back to the big ship for a landing and a new takeof before doing the same again legal ? I see that there is nothing against it in the rules. But would you allow it ?

It allso looks like you forgot some digits in your score calculations somewhere. http://www.wolframalpha.com/input/?i=%282.5*%282-1%29^2*100%29%2B%28%282.797%2F1110.166%29*50000%29 says your score is 375.9721519124167016464204452307132446859298519320534046259748...

Yes. Totally legal so long as you land the ship on Kerbin and then launch again from Kerbin's surface.

And you're right about the score. I redid the scoring system in the middle of writing the challenge and forgot to update my own score.

[Mesklin]

Is it no any restriction for using turbojets and ion engines?

[Vaporo]

Is it no any restriction for using turbojets and ion engines?

Nope. None. All stock engines are fair game.

[chengong]

Reserved for entry

[KerikBalm]

Methinks laythe is the place to go. Turbojets get you to orbit, aerobraking gets you the capture and to the surface. You only need significant fuel for the transfers.

Although, duna works out in a similar way.... you can get more aerobrakings per m/s dV needed for transfers... but you can't turbojet to orbit

[Wanderfound]

Cool. Spaceplane + lander time. I wonder how many times I can get Brutus to Minmus and back on a single tank?

Edited September 20, 2014 by Wanderfound

[Vaporo]

I increased Tylo's multiplier from 5 to 5.5.

Edited September 20, 2014 by Vaporo

[Wanderfound]

Any bonus for leaving no space junk behind at all? I'm thinking of doing pseudo-Apollo: spaceplane to orbit, deploy a docked-together transfer stage + lander, sending them to the Mun or Minmus and back, return them to the spaceplane cargo bay where they'll be refuelled, land the whole lot back at KSC, rinse and repeat as many times as possible.

Why the limit on the mass ratio?

[Vaporo]

Any bonus for leaving no space junk behind at all? I'm thinking of doing pseudo-Apollo: spaceplane to orbit, deploy a docked-together transfer stage + lander, sending them to the Mun or Minmus and back, return them to the spaceplane cargo bay where they'll be refuelled, land the whole lot back at KSC, rinse and repeat as many times as possible.

Why the limit on the mass ratio?

No bonuses for leaving no junk behind at the moment, but it's something to think about.

I limited the mass ratio bonus because I thought it could be too easily abused to get high scores. If someone managed to build something with a 1-10 end mass to start mass ratio, that's 5000 points right there, and it doesn't matter as much where you actually went. It's meant to encourage people to try for places aside from the Mun. I'll consider raising the limit to tripling the score, though.

Edit: Working on a new "bonuses" section for things like leaving no debris.

Edited September 20, 2014 by Vaporo

[Wanderfound]

How about lowest total √ cost after recovery?

Edited September 21, 2014 by Wanderfound

[Vaporo]

How about lowest total √ cost after recovery?

That could be a good mini challenge.

[sdj64]

Is it allowed to leave a fuel tank in orbit around Kerbin when going to the Mun? Or when landing on Kerbin and taking off again? I'm thinking, small SSTO ship and giant fuel tank go up on initial launch, then Mun, fuel, land, fuel, Mun, repeat.

[Vaporo]

Is it allowed to leave a fuel tank in orbit around Kerbin when going to the Mun? Or when landing on Kerbin and taking off again? I'm thinking, small SSTO ship and giant fuel tank go up on initial launch, then Mun, fuel, land, fuel, Mun, repeat.

Rule 4 prohibits leaving fuel in orbit when landing on Kerbin. However, you may leave a fuel tank in orbit over Kerbin when going to other bodies.

[Wanderfound]

This is still a work in progress, but I figured I'd give you a look at what the Kerbodyne factory team are up to.

One extended-range Kerbodyne Brutus ready to go.

Bit of a heavy takeoff. Plenty of juice on board.

Away we go.

Cruisin'.

Rocket time.

RAPIERs off, cruise on the nukes.

Coasting to apoapsis.

Circularise.

And open the doors.

Pop 'em loose.

Join up.

Get some room.

And fire up.

Off to the Mun.

Capture.

Hit the brakes.

Gas it up again.

Ta-da!

Back to big sister.

And off to mother.

Home again.

Home again.

Jiggedy-jig.

Struts in place.

Ready to glide back to KSC. Mitvis can ride up the back and keep an eye on the cargo.

There was plenty of juice in that transfer stage when it came back; this could do more distant moons that this.

[gchristopher]

Here's another attempt in progress!

[table=width: 900, align: left]

[tr]

[td]

SPH view[/td]

[td]

Takeoff![/td]

[td]

Air intake abuse gets us to a 68.6km semi-major axis using only jets.[/td]

[td]

Mun landing #1[/td]

[/tr]

[tr]

[td]

Docking, lazily letting Mechjeb align both craft.[/td]

[td]

Attaching KAS struts. (Still very weak and floppy)[/td]

[td]

Kerbin landing #1.[/td]

[td]

Back to LKO.[/td]

[/tr]

[tr]

[td]

Mun landing #2.[/td]

[td]

Kerbin landing #2: overshot the runway and had to turn around and land from the east.[/td]

[td]

Back in orbit.[/td]

[td]

Mun landing #3.[/td]

[/tr]

[tr]

[td]

Kerbin landing #3, didn't do quite as well at aiming at the runway.[/td]

[td]

Mun landing #4.[/td]

[td]

Kerbin landing #4. Descent was mostly an uncontrolled tumble! TAC fuel balancer saved it in the final moments by restoring a flyable COM![/td]

[td]

Mun landing #5.[/td]

[/tr]

[tr]

[td]

Kerbin Landing #5: almost overshot the runway again. A dramatic S turn brought it in.[/td]

[td]

Mun Landing #6.[/td]

[td]

Kerbin Landing #6.[/td]

[td]Low-angle approaches to steep terrain were typical.[/td]

[/tr]

[tr]

[td]Landings were not always picture-perfect.[/td]

[td]Mun Landing #7: toggling landing legs works to right the lander again![/td]

[td]Kerbin Landing #7[/td]

[/tr]

[/table]

This attempt is using all stock physics. Mods are mostly for automation (MechJeb and TAC fuel balancer), reducing part count (Procedural Wings and welded/multiplied air intakes), and KAS struts to stabilize the lander on the launch vehicle, instead of fiddling with multiple docking ports.

The vehicle is a horrendously air intake abusing spaceplane. Its stats are:

Launch Mass, 97.922t, Cost: 171,258.6√, 1 LV-N on the lander, 12 TurboJets, 120(!) Ram Air Intakes, LiquidFuel: 9540, Oxidizer: 2508, Monoprop: 115

Part count is 141, but would increase by ~100 without procedural wings and by another 216 without welded air intakes. (But performance should be nearly identical, other than a sad CPU.)

Here's the resource log at each runway stop on Kerbin:

[table]

[tr]

[td][/td]

[td]LiquidFuel[/td]

[td]Oxidizer[/td]

[td]Mass[/td]

[td]Usage: (LF/Oxy)[/td]

[/tr]

[tr]

[td]Launch[/td]

[td]9540[/td]

[td]2508[/td]

[td]97.922t[/td]

[td][/td]

[/tr]

[tr]

[td]Landing #1[/td]

[td]8064[/td]

[td]2121[/td]

[td]88.602t[/td]

[td](1476/387)[/td]

[/tr]

[tr]

[td]Landing #2[/td]

[td]6870[/td]

[td]1759[/td]

[td]80.817[/td]

[td](1194/362)[/td]

[/tr]

[tr]

[td]Landing #3[/td]

[td]5806[/td]

[td]1453[/td]

[td]73.948[/td]

[td](1064/306)[/td]

[/tr]

[tr]

[td]Landing #4[/td]

[td]4863[/td]

[td]1149[/td]

[td]67.714[/td]

[td](943/304)[/td]

[/tr]

[tr]

[td]Landing #5[/td]

[td]4033[/td]

[td]848[/td]

[td]62.059[/td]

[td](830/301)[/td]

[/tr]

[tr]

[td]Landing #6[/td]

[td]3228[/td]

[td]557[/td]

[td]56.523[/td]

[td](805/291)[/td]

[/tr]

[tr]

[td]Landing #7[/td]

[td]2432[/td]

[td]225[/td]

[td]50.524[/td]

[td](796/332)[/td]

[/tr]

[/table]

At this rate, it looks like another two round trips to the Mun should be possible before running out of oxidizer just short of a third trip, but I didn't think through COM very carefully, with all the engines and intakes loaded on the back of the craft, so it might become unflyable before then. (Still, if it makes 7 trips, that's better than the 6 I thought I'd get at the start.)

I think the score at this incomplete stage is:

Mun multiplier: 2.5, Trips: 5, Start Mass: 97.922, End Mass: 62.059

(Mult*(Tr-1)^2*100) = 4000 + ((Em/Sm)*50000) = 31688 (capped at 4000)

Um, bonuses would be Junk hoarder: 200 (not cumulative with No Junk Left Behind?), Manning the Guns: 100?

So, the score so far is 8300. As time permits, let's see if it can make any more trips!

This entire thing is an exercise in ridiculous airhogging, which is pretty darn exploit-ey. Maybe the score deserves an asterisk and a frowny face?

edit: Trip 7 is complete, for a score of 18,400. And that's as far as we're getting, because the oxidizer won't last for another round trip!

Edited September 28, 2014 by gchristopher

[cyberklad]

Here's another attempt in progress!

So, the score so far is 8300. As time permits, let's see if it can make any more trips!

Your best score will be after just 2 trips. You have a score at over 41.000 there. the higher the % of the craft that comes back after the seccond trip. The closer to 50k score you will get.

[Vaporo]

I think the score at this incomplete stage is:

Mun multiplier: 2.5, Trips: 5, Start Mass: 97.922, End Mass: 62.059

(Mult*(Tr-1)^2*100) = 4000 + ((Em/Sm)*50000) = 31688 (capped at 4000)

Um, bonuses would be Junk hoarder: 200 (not cumulative with No Junk Left Behind?), Manning the Guns: 100?

So, the score so far is 8300. As time permits, let's see if it can make any more trips!

This entire thing is an exercise in ridiculous airhogging, which is pretty darn exploit-ey. Maybe the score deserves an asterisk and a frowny face?

All bonuses stack, so your score as of right now would be 8400.

And yes, I do believe I will add an asterisk because of the airhogging (Rule 7). However, you will still certainly be on the scoreboard.

Your best score will be after just 2 trips. You have a score at over 41.000 there. the higher the % of the craft that comes back after the seccond trip. The closer to 50k score you will get.

Nope. The % start weight maximizes at doubling your score.

Edited September 22, 2014 by Vaporo

[gchristopher]

And yes, I do believe I will add an asterisk because of the airhogging (Rule 7). However, you will still certainly be on the scoreboard.

Totally agreed. (Or with omitting it entirely.) I just don't know how to draw a line between "reasonable" air intake usage and "airhogging." 3 intakes per engine is often considered a minimum for a useful spaceplane. Is 5-6 per engine excessive? This one is 10 per engine, which is definitely excessive. Do you try to not clip them and at what point is covering a wing with intakes considered too much?

Either way, this has been fun! Thank you! It's really interesting to try to figure out just how much travel you can get out of a single launch.

[Wanderfound]

"Does it vaguely resemble something that might possibly fly in the real world?" usually works for me. But it's inevitably a subjective preference sort of deal.

[gchristopher]

Yeah, Kerbal kinda inspires me in the opposite direction of realism for rockets and planes.

Okay, done with the challenge attempt! (image gallery)

This one managed 7 round trips to the Mun and back. Here are the stats:

Launch Mass, 97.922t, Cost: 171,258.6√, LiquidFuel: 9540, Oxidizer: 2508

Final Mass: 50.524t, Recovery Value: 165029.17√ (100% on Runway), LiquidFuel: 2432, Oxidizer: 225.

Mission Cost: 6229.43√ (Under 900 Funds for each round trip to the Mun, pretty cheap!)

The remaining liquid fuel seems to imply that with a little better starting resource planning and much more consistent piloting, this design is probably capable of up to 9 round trips.

So, the final score is:

Mun multiplier: 2.5, Trips: 7, Start Mass: 97.922, End Mass: 50.524

(Mult*(Tr-1)^2*100) = 9000 + ((Em/Sm)*50000) = 25798 (capped at 9000)

Bonuses are No Junk Left Behind: 100, Junk hoarder: 200, Manning the Guns: 100

That makes a total score of 18,400.

Thanks for the fun challenge! That was quite a lot of flying.

My other idea is to do a high TWR subobital hop using a jet-powered booster plane, near-vertical, then release a lightweight stage. Circularize the small piece, then switch back and land the booster plane before it crashes.

I really wanted to put a front-facing jet on the plane and dangle the small lander section out in front like a deep-sea fish lure, then use a hotkey to release the lander and fire the jet simultaneously, shooting it away from the booster plane like a cannon. This works, but sadly, it only gets you about 300dv, which isn't really worth the rocket weight and fuel usage, even for a split-second firing.

Oh well, without the cannon, that method isn't really fun enough to be worth it, even if I suspect it'd allow for an overall higher number of trips.

[SkyRender]

I have a suggestion for both a bonus and a new factor in scoring: account for how many Kerbals are sent on the mission. Why?

'Cause I'm totally sending 10 Kerbals out on this crazy mission. Have I mentioned that sanity is for the weak?

[Vaporo]

Yeah, Kerbal kinda inspires me in the opposite direction of realism for rockets and planes.

Okay, done with the challenge attempt! (image gallery)

This one managed 7 round trips to the Mun and back. Here are the stats:

Launch Mass, 97.922t, Cost: 171,258.6√, LiquidFuel: 9540, Oxidizer: 2508

Final Mass: 50.524t, Recovery Value: 165029.17√ (100% on Runway), LiquidFuel: 2432, Oxidizer: 225.

Mission Cost: 6229.43√ (Under 900 Funds for each round trip to the Mun, pretty cheap!)

The remaining liquid fuel seems to imply that with a little better starting resource planning and much more consistent piloting, this design is probably capable of up to 9 round trips.

So, the final score is:

Mun multiplier: 2.5, Trips: 7, Start Mass: 97.922, End Mass: 50.524

(Mult*(Tr-1)^2*100) = 9000 + ((Em/Sm)*50000) = 25798 (capped at 9000)

Bonuses are No Junk Left Behind: 100, Junk hoarder: 200, Manning the Guns: 100

That makes a total score of 18,400.

Thanks for the fun challenge! That was quite a lot of flying.

My other idea is to do a high TWR subobital hop using a jet-powered booster plane, near-vertical, then release a lightweight stage. Circularize the small piece, then switch back and land the booster plane before it crashes.

I really wanted to put a front-facing jet on the plane and dangle the small lander section out in front like a deep-sea fish lure, then use a hotkey to release the lander and fire the jet simultaneously, shooting it away from the booster plane like a cannon. This works, but sadly, it only gets you about 300dv, which isn't really worth the rocket weight and fuel usage, even for a split-second firing.

Oh well, without the cannon, that method isn't really fun enough to be worth it, even if I suspect it'd allow for an overall higher number of trips.

Hooray, first complete entry! I'll recalculate your score myself tomorrow. For now, I'll take your word on it and go to bed.

[Rakaydos]

When you deploy the whole roocket, all the fuel, and so on in one launch.... Does it all have to reach kerbin orbit? Or can you leave tanks on the runway, and dock with tham after the first landing to refuel?