Life On Laythe science mission

[camacju]

5 hours ago, jinnantonix said:

1.  The use of the airlock is brilliant.  And very Kerbal, I am imagining Jeb floating in the airlock for 20 years.  However it is not actually a pressurized seat as stated in the rules.  It is so clever though, I will avoid being pedantic, and allow it.

He's not really floating in there for 20 years. Jeb starts by sitting in the return vehicle's command pod and Bill starts in the Laythe lander. After the Laythe ascent I throw away the Laythe lander's command pod and then Jeb crawls into the airlock.

Maybe he has a folding chair in there, otherwise it wouldn't be very comfy. But it is pressurized - it has to be, otherwise it wouldn't be inflated. Additionally in your clarification you specified "no command chairs."

5 hours ago, jinnantonix said:

2.  I have tested your craft re-entry at both Laythe and Kerbin with modest velocities (<3 km/s)  and spinning etc, yet the craft explode every time.  What am I missing?  Can you please check you have the default setting for re-entry heating of 100%, you may have changed it in a previous game and forgotten to reset it.  Or advise your re-entry speeds and altitudes, and I will check again.

It's possible that I had set reentry heating to less than 100%. However I did try to do as gentle of an aerobrake as I could (My Laythe periapsis was only 5 km into the atmosphere) and tried to do low relative velocity encounters hence the Kerbin and Eve assists to get back. So maybe that's the difference.

If it's necessary, I can try to re-fly the Laythe and Kerbin entries using a more aggressive gravity assist route for easier aerobraking, and then I could show you the heights and entry velocities.

Additionally the crafts aren't put together in the way they look. They both take advantage of node occlusion and part inlining (No clipping however) in order to reduce drag cubes which also reduces heating.

 

Edit: I looked back at my screenshots and my Laythe aerobrake does show 100% reentry heat with 45.4 km periapsis and 2387 m/s velocity. Laythe orbital velocity as shown in the screenshots is 1793 m/s and it takes about 600 m/s to escape Laythe which implies a minimum aerobrake speed of 2393 m/s - this is reasonable as I am passing periapsis in the screenshot and have bled off a bit of speed. So the Laythe aerobrake seems to check out. If you aren't convinced then I can re-fly the aerobrakes and maybe record video.

 

5 hours ago, jinnantonix said:

3.  The EVA and use of jet packs is clever , although I think not really in the spirit or the challenge, it is within the stated rules, so I have to allow it.  Can you provide an image showing your kerbal EVA at Laythe is when the craft is outside the atmosphere.  EVA in atmosphere is against the stated rules.   My testing shows that the craft cannot get to an Ap >50km.  Perhaps I have missed something?

The Laythe lander had more work put into it than it might seem at first. The Oscar tanks were attached at the top of the lander and offset downward into the cargo bay, and the Donut tanks were attached to the bottom of the lander using an adapter and offset upward into the bay. This reduces the drag cube of the lander significantly which makes it a lot more drag efficient.

I also took a steep trajectory to give myself more time above the atmosphere for the low thrust of the jetpacks to circularize the orbit.

Edited May 1, 2021 by camacju

[Guest]

15 minutes ago, camacju said:

Additionally the crafts aren't put together in the way they look. They both take advantage of node occlusion and part inlining (No clipping however) in order to reduce drag cubes which also reduces heating.

I’m not familiar with this optimization technique, could you expand on it? Does it mean that if e.g. you attach a part behind another part, then offset it to the side, the drag model still thinks it’s behind it and you get less drag? Or conversely if you want more drag but a slimmer profile, you can surface attach to the sides, then offset so it’s behind without affecting total drag?

Does this also work if you attach a part to a node, then offset it? I.e. does the drag model still think it’s node attached rather than surface attached?

 

[camacju]

Yes, that's correct. KSP's drag model is weird. Basically each part is a cube, and by attaching parts by nodes, you change the surface area of the cubes. KSP calculates drag based on cube surface area.

It's a bit more complicated than that but that's basically all you need to do it

[jinnantonix]

@camacju can you please submit your craft file.  I must be missing something in the way I am reconstructing your craft.

[jinnantonix]

Here is the first launch tests of my "cool and fun" entry.  With spin gravity.

 

Edited August 9, 2021 by jinnantonix

[Guest]

I wanted to see if I could do this in a single launch and single stage (excluding the bathysphere). I could! And it wasn't even too hard or tedious! Here's a SSTLAB (Single Stage To Laythe And Back) sea/spaceplane, carrying two kerbals and the bathysphere as an external payload. I haven't decided what to name it yet, the working name is XR-8. She has about 6000 m/s vacuum dV upon reaching 100 km Kerbin orbit. At Laythe she had about 4000, and back in LLO she had about 3000, which was plenty for a nice and easy return to Kerbin. I just muffed my timing a bit and overshot KSC by some tens of km and had to make another water landing. Good thing she's built for that. 

FWIW I managed this without any savegame abuse, too.

The plane was a bit more expensive than the first one (59,052) but the total mission cost was a quite a bit less as it didn't need the service module and refueling flight that came with it. Simpler, too, obviously, as there was only one craft to fly.

(There's a bit of cosmetic clipping here but nothing that should affect performance or characteristics.)

Edit: Her name is BAK Billbo, because she goes there and back again and I don't want to be sued for copyright infringement.

Edited May 7, 2021 by Guest

[Pastapower]

Are you allowed to use better time warp to speed up the mission and do you get extra points if you do more science? Please answer I really need to know 

Edited May 9, 2021 by Pastapower

[camacju]

I used bettertimewarp so I assume it's allowed. I can't find any reason why it wouldn't be

[jinnantonix]

18 hours ago, Pastapower said:

Are you allowed to use better time warp to speed up the mission and do you get extra points if you do more science? Please answer I really need to know 

bettertimewarp is allowed.  There are no extra points for more science.

[Pastapower]

I have one more question:

Does the return capsule have to land or can I save weight by having no parachute and using the kerbal’s personal ones?

[camacju]

Atmospheric EVA isn't allowed - no paragliding

[jinnantonix]

Here is my "cool and fun" submission.  Craft cost 71,180 funds, but low cost wasn't the agenda, rather I wanted to try to replicate the artificial gravity system and the space craft design used in the video Astronaut: The Last Push.  I used a KEKKJ transfer with Tylo assist to Laythe using about 1600 m/s dV (I think I could have done better by 350 m/s with more care) , and then a single Tylo assist direct to Kerbin which only cost about 1000m/s dV from low Laythe orbit.  I used heat shields with 200 units of ablator at both Laythe and Kerbin to assist with aerobraking.

 

Edited May 14, 2021 by jinnantonix

[Guest]

That is very cool! I haven't bothered with centrifugal gravity designs in KSP because the rotation isn't persistent; one of the things I'm looking forward to in KSP2 is that it will be so we'll see more designs like this.

 

[jinnantonix]

On 5/14/2021 at 5:35 PM, Brikoleur said:

That is very cool! I haven't bothered with centrifugal gravity designs in KSP because the rotation isn't persistent; one of the things I'm looking forward to in KSP2 is that it will be so we'll see more designs like this.

Thanks.  I have been wanting to do this mission in KSP forever.  Finally got to do it.  Looking forward to KSP2.

[Death Engineering]

Apollo to Laythe.. coming soon!

[camacju]

I had some ideas to reduce costs even further. Second ultra low cost submission: 12960 funds

Craft is very similar to the other one I submitted, but stripped down further. It consists of four parts:
-Laythe ascent vehicle: cheaper, lighter, more delta-v, and more TWR than the previous mission. Could probably be even lighter/cheaper but that's a lot of effort for what's probably minimal gain.
-Descent module: fuel tanks for ballast, parachutes, goo canister
-Station: Mk1 crew cabin and probe core (lighter and cheaper than two Mk1 command pods), fuel, Terrier engine. Like the previous mission, Terrier is used for orbital insertion, the trip to Laythe, and the return
-Two stage SRB launcher: No Kickback boosters this time; Thumpers are enough

On pad

Gravity turn

Second stage ignition

Coast to 60km

Orbital insertion

Kerbin orbit

For this mission I'm trying something new for gravity assists. Sometimes my Mun assists won't give me enough energy for a good orbital resonance, or the angle won't be right - like this time.

Mun transfer

I use Mun assists to get to Minmus, where I fly by Minmus and then fly by Mun one last time.

Now I can get a good resonance

Minmus flyby

Final Mun assist

Next: Gravity assists to Jool

[Death Engineering]

Hi @jinnantonix,

Thanks for this challenge, which has me doing submersible design for the first time (somehow...)!

Couple of questions:

 

1.  Does Re-stock count as a 'visual' mod?

 

2.  Couple of Part Clipping General thoughts:

This pic shows an example of how I tend to clip parts - not exploitive, and within reason, to accomplish something that seems within engineering capability.  Here, a Jr. docking port is nested within a standard docking port to create a universal port.

Here, the mission profile calls for an 'Earth Entry Module', which is a "modified Apollo CSM with beefed up heat shield and radiation shielding". To model that in KSP, this is a structural adapter clipped in with a 3-crew re-entry pod and some logistics (battery, chutes and a probe core). It weighs in at 3.9t (after departing from the Mission Module).

 

Based on what you see here, am I out of line with the clipping?

Thanks!

[jinnantonix]

@Death Engineering Restock is fine, and your clipping is legal.

[camacju]

The trip to Jool

Because of the Minmus assist I had more Kerbin relative velocity than normal so I can go straight into an Eve encounter from the Kerbin assist

Kerbin flyby

Mun flyby for plane change

Eve assist

Kerbin and Eve assists

Second Eve assist

Jool encounter

Final Kerbin assist

Tylo and Laythe assists to slow down for aerobraking

Necessary because otherwise aerobrake speed would be far too high

After the assists, aerobrake is a much more manageable speed

Laythe aerobrake

Lander detaches

Aerobraking

Chute deployed

Descending

[jinnantonix]

@camacju it looks like you have a Kerbal in a deflated airlock, and also that you are inflating it through a fairing.  That's an illegal clip/exploit.  Sorry.

[camacju]

53 minutes ago, jinnantonix said:

@camacju it looks like you have a Kerbal in a deflated airlock, and also that you are inflating it through a fairing.  That's an illegal clip/exploit.  Sorry.

Inflated or deflated makes no difference to the aero properties. I'll re-fly the mission without that.

 

[Death Engineering]

Apollo to Laythe - McDonnell Douglas Phase B 12-Man Space Station Launch

This mission to the bottom of Laythe's ocean world incorporates some of the more far-out NASA concepts from the early 1970's, mixed in with a healthy dose of just plain Kerbalistic nonsense. 

In the first Saturn V launch, is the crew quarters, inflatable heat shield for Jool/Laythe braking and the crew Kerbin return capsule. The Phase B station was to be "a 12-man Space Station, the design of which would eventually serve as a building block for a 100-man Earth-orbital Space Base. The 12-man Space Station was to reach orbit on a Saturn V rocket in 1975 and to remain in operation for 10 years."

The crew are launched aboard a modified Apollo capsule affixed to the top of the Phase B, then undock and maneuver to the inflatable docking port to board their main vessel. The Apollo capsule is discarded and the crew await the next launch of the propulsion stage and Laythe lander.

  

With such a life-span, a trip to Jool seemed like a natural choice for this mission. In the picture, a small Crew Module is seen docked to the rear (?) of the Phase B. For my purposes, a nuclear propulsion module is docked there instead.

 

Once the crew and Laythe SSTO seaplane are on their way, the nuclear booster will undock and return to Kerbin orbit for reuse. Before the mission gets underway, a full dress rehearsal is executed as a Munar flyby with a very shallow Kerbin re-entry to test the inflatable heat shield. 

Once this high-speed re-entry test is completed, a new Phase B and propulsion stage will get the crew on the way to Laythe!  We won't be planning any extreme ▲-V saving flybys, but there will be Tylo gravity braking into Laythe orbit. The heat shield may or may not be needed, but nice to have it anyways, haha!

Coming next..

 

Edited June 18, 2021 by Death Engineering

[Death Engineering]

Apollo to Laythe - McDonnell Douglas Phase B 12-Man Space Station 

Bob stood on the bow of their spaceplane and, after tucking the DeGrasse Sea science into the hold, took one last look at the distant SOL and how different it looked shimmering with Laythe's pastel-pink sunset.

Thanks @jinnantonix for this challenge - I'd not ever attempted to sink anything (on purpose)!

We arrived at Jool with a quick gravity assist past Tylo before aerobraking into Laythe orbit. Total ▲V to enter low Laythe orbit from interplanetary space was just a few hundred m/s.

 

It was a very light pass through Laythe's atmosphere to slow down, then ditched the heat shield.

 

After waiting for their landing zone to roll into daylight, the crew separated from the Phase B and headed down, brakes on FULL.

 

Landing on chutes was the safest way to go. With no time to waste, they opened the door and dropped the probe.. wayyyyy down!

The view from the bottom was eerie.. need a sub next time!

Payload back on board, the crew jetted... then rocketed.. back to orbit. 

 

No docking ports on the spaceplane, so a quick EVA got them back on board, then a long burn home for a 2.5 year cruise.

Don't forget the Mystery Goo!!

Back home safe and sound... until next time!