Space Race

[CairoJack]

The rules of this challenges are very simple:

Start a new carrier game with normal settings and land on a planet with the least number of launches you can. There are different leaderboard for one-way missions and return missions.

Cheats, alt f12 and mods are not permitted

 

This is my entry:

 

 Leaderboard:

Return:

4 launches:

@CairoJack duna

 

One way: 

2 launches:

@ManEatingApe & @Kergarin Duna, Eve & Eeloo 

@ManEatingApe Duna &Eeloo

Edited April 16, 2018 by CairoJack

[ManEatingApe]

Career mode golf - I'm in! Started new career game, normal difficulty, stock, no mods.

2 missions total.

Valentina went to Duna...

..and Jeb went to Eeloo.

 

First Mission Highlights

Spoiler

My trusty Caveman opener. It carries 5 Goos and can reach space on a sub-orbital trajectory.

Maximum velocity.

AP is comfortably out of the atmosphere.

Plenty of funds from Worlds First awards, enough to unlock the level 2 launchpad.

Plenty of science for the first few nodes. The "Advanced Rocketry" node is crucial as it unlocks the Terrier.

Second Mission Highlights

Spoiler

When all you have is a hammer... 
A two ship behemoth consisting mostly of Hammers duct-taped together.
The 30 item part limit favours fewer larger SRBs over liquid fuel engines even though they're less efficient.

Slightly offsetting the bottom stage induces a gravity turn without needing control surfaces or gimbal.

In LKO. After doing the sums, we have 3,960 m/s dV in the right craft and 2,740 m/s dV in the left craft.

The left craft went first as it had an earlier transfer window. Pictured here braking into Duna capture and landing.

Executing the Eeloo manouver node was tricky and required a correction burn...and then a correction burn for the correction burn!

Ran out of fuel near Eeloo surface. I'd like to say that this was intentional, but nope, just completely forgot to budget for landing. 

Jump for it Jeb!

 

It was a close call and a slightly bumpy landing but Jeb (and the flag) made it intact.

 

Complete Album link

Edited April 11, 2018 by ManEatingApe

[Kergarin]

That's was impressive @ManEatingApe 

Could your design also do 3, if you pic eve, duna and laythe? It seems you have a lot of fuel to spare, and if you aerobrake and land on chutes, you save even more. But the part count makes this impossible, right?

[ManEatingApe]

1 hour ago, Kergarin said:

Could your design also do 3, if you pic eve, duna and laythe? It seems you have a lot of fuel to spare, and if you aerobrake and land on chutes, you save even more. But the part count makes this impossible, right?

You're right, dV would be adequate (especially with free aerobraking) however part count is the limiting factor that makes this tricky.

The craft is exactly at the 30 part limit, so each extra command pod, parachute or separator means sacrificing a fuel tank or booster.
I also suspect a heat shield would be needed for Eve which is another part. (It would also require unlocking another node during the first mission, but that's not impossible)

I'd love to see someone try it!

[MarvinKitFox]

Watches ManEatingApe start a career, 2 missions, and get to both Duna and Eeloo.

.

Picks jaw up from ground.

Considers sweeping up shattered ego, but its too finely broken to bother....

.

wow!

[Kergarin]

17 hours ago, ManEatingApe said:

You're right, dV would be adequate (especially with free aerobraking) however part count is the limiting factor that makes this tricky.

The craft is exactly at the 30 part limit, so each extra command pod, parachute or separator means sacrificing a fuel tank or booster.
I also suspect a heat shield would be needed for Eve which is another part. (It would also require unlocking another node during the first mission, but that's not impossible)

I'd love to see someone try it!

Hm... That would mean to copy your launcher, what I usually don't like to do.

But I could try to build an upper stage for it. What's the part count of it? 12? That's hard 

What if we wait for a window where we can slingshot around Duna to get to Jool/laythe? We could drop a landing pod on the flyby and only need two engines for 3 pods  have to check if that's possible with the available parts...

[Kergarin]

@CairoJack

Does it have to be a planet, or are moons from other planets ok too?

And is making history allowed?

[Kergarin]

@ManEatingApe

What about something like this?

12 parts, 2 parachute landers, 1 low gravity lander.

Quick explosive decoupling. You just have to get all three quick into orbit 

[ManEatingApe]

2 hours ago, Kergarin said:

But I could try to build an upper stage for it. What's the part count of it? 12? That's hard 

Good idea - a challenge collaboration to see how far we can push things!
 

25 minutes ago, Kergarin said:

What about something like this?

This looks very promising  Could you post a link to the craft file?
Let's strap it to the top of the Spartan 3 and see what we can do!

Edited April 14, 2018 by ManEatingApe

[Kergarin]

1 minute ago, ManEatingApe said:

Good idea - a challenge collaboration to see how far we can push things!
 

This looks very promising
Let's strap it to the top of the Spartan 3 and see what we can do!

Yes, if you like to 

Would like to try and optimize this? I'm short on time.

The "explosive decoupler" was mounted inline between the middle lander and the booster with side attached landers, then rotated 90 degrees and rearranged the attached parts.

 

[Kergarin]

@ManEatingApe I found some time and quickly strapped together this one:

It needs further optimization, and I have no clue where to send them 3. (one to duna obviously) but is has a lot of fuel left in LKO and decoupling works fine 

 

Edited April 14, 2018 by Kergarin

[Kergarin]

I think 5 landings on second launch are possible 

[ManEatingApe]

2 hours ago, Kergarin said:

It needs further optimization, and I have no clue where to send them 3. (one to duna obviously) but is has a lot of fuel left in LKO and decoupling works fine 

Nice! What's the dV of the various craft?
Given they all have chutes Eve, Duna and Laythe feel like good choices.

1 hour ago, Kergarin said:

I think 5 landings on second launch are possible 

I've also been iterating designs based on your payload.

First iteration, very respectable performance - your girder decoupler idea works like a charm.

Replacing the final Hammer with a Swivel gave better control, better dV and recharged the batteries.

Some testing showed that Eve re-entry requires a heat shield, so the craft is now slightly asymmetric and I've added another tank to the centre craft at the cost of 2 boosters total.

In LKO.  Doing the dV calculations gives:

• Top craft 2,010 m/s
• Middle craft 3,960 m/s
• Bottom craft 2,190 m/s

 

I started another fresh career game. To get the extra science to unlock the heat shield I had to use my un-trusty Caveman opener the Whatever you do, don't look down. Bob was sent to space with only a Goo canister acting as a step between him and certain doom.

Manoeuvre nodes unlocked, 3rd pilot hired, craft in orbit ready to go.
Mission album so far...

 

@Kergarin Would you like to continue our joint mission? Eve, Duna and Eeloo are looking tempting...
Space Race save file

Edited April 14, 2018 by ManEatingApe

[CairoJack]

7 hours ago, Kergarin said:

@CairoJack

Does it have to be a planet, or are moons from other planets ok too?

And is making history allowed?

1) It can be also a moon

2) Yes

@ManEatingApe Your entry was absolutely amazing but I forgot to say that returning to Kerbin is needed. I'll do a separate leaderboards for the missions like yours.

[ManEatingApe]

32 minutes ago, CairoJack said:

...but I forgot to say that returning to Kerbin is needed. I'll do a separate leaderboards for the missions like yours.

Separate leaderboards for one-way vs return is a good idea as the strategies are completely different.
Can I suggest you edit the OP to avoid future confusion.

32 minutes ago, CairoJack said:

1) It can be also a moon

Just to clarify are Mun/Minimus included?

Edited April 14, 2018 by ManEatingApe

[CairoJack]

23 minutes ago, ManEatingApe said:

Just to clarify are Mun/Minimus included?

Yes, but I think they have already been done in two launches in an old challenge

[ManEatingApe]

13 minutes ago, CairoJack said:

Yes, but I think they have already been done in two launches in an old challenge

That was me... 

https://forum.kerbalspaceprogram.com/index.php?/topic/164065-space-race/&do=findComment&comment=3196533

[Kergarin]

4 hours ago, ManEatingApe said:

Nice! What's the dV of the various craft?
Given they all have chutes Eve, Duna and Laythe feel like good choices.

I've also been iterating designs based on your payload.

First iteration, very respectable performance - your girder decoupler idea works like a charm.

Replacing the final Hammer with a Swivel gave better control, better dV and recharged the batteries.

Some testing showed that Eve re-entry requires a heat shield, so the craft is now slightly asymmetric and I've added another tank to the centre craft at the cost of 2 boosters total.

In LKO.  Doing the dV calculations gives:

• Top craft 2,010 m/s
• Middle craft 3,960 m/s
• Bottom craft 2,190 m/s

 

I started another fresh career game. To get the extra science to unlock the heat shield I had to use my un-trusty Caveman opener the Whatever you do, don't look down. Bob was sent to space with only a Goo canister acting as a step between him and certain doom.

Manoeuvre nodes unlocked, 3rd pilot hired, craft in orbit ready to go.
Mission album so far...

 

@Kergarin Would you like to continue our joint mission? Eve, Duna and Eeloo are looking tempting...
Space Race save file

I have no clue about the dv, because I have no mod to display it 

Even more science on first launch? That's crazy 

I have also replaced the last stage with a swivel, as you can see on my last picture, also I have used it as engine for the middle ship to save some parts, and attached the outer ships on separate "decouplers" Would be interesting, which version is more efficient.

For the hammers I find 7-3-1 is good per stage.

Thanks a lot. I would like to continue, but I'm to short on time to execute this completely. I can only give some ideas at the moment. So please go on if you like. 

Actually I'm thinking about extending it to a one way Jool5 on second launch 

[ManEatingApe]

20 hours ago, Kergarin said:

I have no clue about the dv, because I have no mod to display it 

Let's do some sums! Using your picture above as a guide and assuming the fuel is evenly distributed in each tank (i.e. no tank priorities were tweaked) then you have:

(762 + 623) / 200 = 6.925 tons of fuel total = 1.385 tons per tank

The dry mass of each side craft is 0.1 + 0.8 + 0.25 + 0.5 = 1.65 tons

The dry mass of the centre craft is 0.1 + 0.8 + 3 * 0.25 + 1.5 = 3.15 tons

Vacuum ISPs of Swivel and Terrier are 320 and 345 respectively.

dV_side = 9.81 * 345 * ln( (1.65 + 1.385) / 1.65 ) = 2,063 m/s

dVcentre = 9.81 * 320 * ln( (3.15 + 3 * 1.385) / 3.15 ) = 2,641 m/s

Potentially you could go to Duna in one side craft, Eve in the centre craft (hopefully using the extra dV to slow down safely) and use the K-E-K-K-J gravity assist sequence to get to Laythe in the other side craft.

 

20 hours ago, Kergarin said:

Actually I'm thinking about extending it to a one way Jool5 on second launch 

That would be neat! 

 

20 hours ago, Kergarin said:

Thanks a lot. I would like to continue, but I'm to short on time to execute this completely. I can only give some ideas at the moment. So please go on if you like. 

 

Will do! Using your top stage it's possible to visit Duna, Eve and Eeloo one-way in a single mission.

Total Missions 2 (as before)

Lumal Kerman went to Duna. Propulsive assisted landing are much easier when the craft is symmetric.

Valentina went to Eve. As she had not levelled up yet, I had to manually keep the craft to within a degree or two of retrograde during re-entry. Even peeking slightly out of the shadow cone of the heat shield would cause the pod to explode.

 

Jeb went to Eeloo. Lesson learnt from last time, so a Jool-Tylo gravity assist cut down dV needed by a few hundred.

There was even some fuel left over!

 

@Kergarin Collaborative challenge success! 
Previous album updated with all mission pics

Edited April 15, 2018 by ManEatingApe

[Kergarin]

@ManEatingApe well done  the most distant and the highest gravity planet plus duna covered on second launch! 

 

So the numbers make clear a separate ascent swivel and 3 terriers are more efficient.

I'm still curious if we can get all 5 available kerbals to somewhere. I imagine at least two or three will travel together in a "bus" and have to land on Eva packs 

[ManEatingApe]

1 hour ago, Kergarin said:

I'm still curious if we can get all 5 available kerbals to somewhere. I imagine at least two or three will travel together in a "bus" and have to land on Eva packs 

That might just work!

Combining your ideas together, how about:

• Kerbal bus to Jool (possibly using K-E-K-K-J route of ~1,200 m/s dV)
• Jetpack landings on Bop & Pol
• Ballistic landing on Laythe of capsule and chute only
• Powered landing on Val

That would give you a Jool-4 

 

EDIT:
I think it's possible to stretch the science obtained in the first mission to also unlock the "General Construction" node.
This makes the Mk1 Crew Cabin available. Throwing together a rough craft gives 4 Kerbals in LKO with 3,725 m/s dV and a detachable capsule with chute.

Edited April 15, 2018 by ManEatingApe

[CairoJack]

Another interesting idea would be landing on the inner planets. Landing on Eve and Duna is possible but Moho would be a very challenging place to land.

Landing also on Dres in the same mission would be fantastic, but I don't know if it is possible.

[Kergarin]

3 hours ago, ManEatingApe said:

That might just work!

Combining your ideas together, how about:

• Kerbal bus to Jool (possibly using K-E-K-K-J route of ~1,200 m/s dV)
• Jetpack landings on Bop & Pol
• Ballistic landing on Laythe of capsule and chute only
• Powered landing on Val

That would give you a Jool-4 

 

EDIT:
I think it's possible to stretch the science obtained in the first mission to also unlock the "General Construction" node.
This makes the Mk1 Crew Cabin available. Throwing together a rough craft gives 4 Kerbals in LKO with 3,725 m/s dV and a detachable capsule with chute.

Yes, but I still want to add Tylo 

From low Tylo orbit it's just one FL-T400 tank to the ground. We just have to get there 

Stretch the first launch again? That's unbelievable 

Do you want to use making history or stay with the base game? The onion pods have an integrated decoupler and so save a part and weight.

1 hour ago, CairoJack said:

Another interesting idea would be landing on the inner planets. Landing on Eve and Duna is possible but Moho would be a very challenging place to land.

Landing also on Dres in the same mission would be fantastic, but I don't know if it is possible.

I think Moho should be possible, but I don't know if a second planet is in there too.

Just a suggestion: what do you think about rearranging the first post? You could order the entries by number of launches instead of planets.

Like:

Return:

4 launches:

@CairoJack duna

 

One way: 

2 launches:

@ManEatingApe & @Kergarin Duna, Eve & Eeloo 

@ManEatingApe Duna &Eeloo

 

[Kergarin]

@ManEatingApe I was thinking about something like this, if you say yes to making history.

This decouplers from top to bottom. (Notice that some onion pods are mounted backwards.)

I could not test, and it might need tweaking. but I imagine the following:

 

The upper stage is for transfer burn fuel and laythe landing (don't know if it might have to less drag to slow down)

The second is a lander for Vall and maybe has some fuel left for maneuvering everything to Bop and Pol before decoupling (if this is even needed) 

The third are just the two pods carrying kerbals for Bop and Pol.

The fourth is the fuel tank to get to low Tylo orbit.

And the fifth is the Tylo lander.

 

[ManEatingApe]

42 minutes ago, Kergarin said:

Do you want to use making history or stay with the base game? The onion pods have an integrated decoupler and so save a part and weight.

To compensate the Onion pods have no reaction wheels, this can introduce some extra challenges.

I'll stick with stock, but you should try your MH design and we can work both angles, especially to try and reach the elusive Tylo! 

I've uploaded the save file with the extra science as a blank canvas (it will work with MH)

Space Race save game 2

42 minutes ago, Kergarin said:

Just a suggestion: what do you think about rearranging the first post? You could order the entries by number of launches instead of planets.

+1 from me, I think it's clearer.

2 hours ago, CairoJack said:

...but Moho would be a very challenging place to land.

Landing also on Dres in the same mission would be fantastic, but I don't know if it is possible.

I always use this wonderful dv map.

Moho is 5,000 m/s dV from Kerbin absolute best case (it's further than Eeloo in terms of dV) so it'll be tough be do-able. You'd probably have to dedicate a single mission to it though.

You could certainly substitute Dres instead of Eeloo as it's only 3,300 m/s away. These folks would appreciate it! 

Edited April 15, 2018 by ManEatingApe