"We Don't need no stinking Science!" Landing and Return Challenge

[PicoSpace]

Fly to [Mun/Duna/Lathe/Tylo?/Eve??], Land, and Return Safely to Kerbin using ONLY Starting Rocketry parts.

Keep your Re-Entry Speed under 2000 m/s on all atmospheres or we will assume you burned up (if you are playing pre-0.2.0)

Lowest Launch Weight for Each Celestrial Body wins!

[Aeolica]

One feels like crawling on all fours after reading it.

[Astroneer08]

Especially after only having sandbox for 10 months.

[Poppa Wheelie]

OK, I'll go first.

I needed to run this mission before 0.2 comes out, because I will begin holiday travel shortly after that, and won't be able to get back to KSP until January.  So this was done in v 0.1.5.

I only used parts from Starting Rocketry.  To The Mun and back.  Launch Mass:  42.86t

All images for the entire mission can be found here:  https://imgur.com/a/RWBogQW

Here are some highlights

Launch to Orbit

Spoiler

Ascending

Drop boosters

Transfer fuel from yellow tanks, and ditch them

Coast to Ap

Stable LKO

Transfer fuel from white tanks to black and grey tanks, and ditch the white tanks

Transfer to Mun

Spoiler

Maneuver plan

Result after burn

Adjusted Pe once inside Mun SOI

Setup Mun capture

Mun Landing

Spoiler

Plan to land at Pe

Horizontal velocity near zero, lower thrust

SAS to Retrograde

Descent

Landed!

Transfer fuel from grey to black tanks

EVA, plant flag, and return to capsule

Game Bugs On Return

Spoiler

Leaving with tanks on the ground did not work

No orbital lines

Tried again, dropping the tanks after liftoff

I attempted a low Mun orbit, but even with no thrust, Ap kept descending, and Pe kept ascending

Direct Return to Kerbin (with no Low Mun Orbit)

Spoiler

Ready for direct return to Kerbin, no Munar orbit

Drop tanks after liftoff

After a few attempts to return directly to Kerbin, and running out of fuel too early, I finally got a Pe within the Kerbin atmosphere, but actually a little too low.  I turned around and adjusted the Pe to where I wanted it

30 Aerobraking passes of Kerbin

So I didn't even attempt to meet the OP's requirement for keeping atmospheric velocity under 2000m/s.  If there is going to be aerobraking, speeds will be above 2000.  I have to believe that, even with the heat system we get with version 0.2, this vehicle would easily survive the aerobraking and final descent.  The engine and fuel tank sitting under the crew capsule should be sufficient "heat shield".  This would definitely work in KSP1.

@PicoSpace, I request that you remove this 2000m/s requirement.  I won't be able to do anything with this mission after version 0.2 comes out until I return from holiday travel in January.  If I need to rerun this landing in 0.2 to demonstrate that it works, it will have to wait until then.

Here are two tables that show the velocities I measured during the 30 aerobraking passes, and during the final descent (31st atmospheric entry)

Spoiler

Altitudes and Velocities during 30 aerobraking passes

Altitudes and velocities during final descent

31st Atmospheric Entry and Final Descent and Landing on Kerbin

Spoiler

Descending at 30,002m

Dropped the engine and tanks and got a good chute

Almost landed

Landed!

A couple of bugs when Jeb got out to plant a flag:

Quicksand on the mountaintop

And invisible terrain on the mountaintop

Jeb preps the flag

[savkerbal]

Thanks for the challenge. Now I understand why I need this stinking science.

[Poppa Wheelie]

Update, 20231220:

I don't think this will work with the current version of the heating system.  I just put an identical vehicle into a 12,000,000m orbit above Kerbin (a little past Mun's orbit), then at Ap I lowered the Pe to 60,421m (almost 100m lower than the mission above).  But the lateral fuel tanks overheated and blew up almost immediately (while still above 60km).

Next, I put the vehicle in a LKO and lowered the Pe to 60,495m.  The lateral tanks also overheated and blew up well above 60km (64,548m, in this case).

So, I'm not sure if it's possible to return from orbit without a heat shield.  I don't intend to try again any time soon, at least until we get an updated reheating model, or until someone else figures out a way to return from orbit without a heat shield.  Maybe you have to zero your horizontal movement and fall straight down?  Someone else is welcome to give that a try.

[Poppa Wheelie]

OK , I'm back from vacation.

And, I successfully completed the mission I attempted earlier, Mun landing and return, using only parts from the initial tech node.  Launch weight:  137.32t

But, I'm not the first to report a successful landing on another celestial body and return to Kerbin using only the initial tech node.  I'm sure there are more, but I've found these 3:

• @Nnamleips reported a Mun and return mission in these forums on 31 December.  Here's that report.  The Kerbin reentry method was a large retrograde burn right before reentry.
• Gregrox reported a Mun and return mission on reddit on 6 January.  Here's that report.  I asked how the reentry was done, and here is the reply:  "Kept the tanks and fins attached. Started with a retrograde gliding reentry but ended up just wobbling back and forth a bunch until I slowed down enough to land normally. It took three tries."
• And Matt Lowne did an Eeloo landing and return on YouTube.  Here's a link to that one.  Matt's reentry method was some intentional wobbling, plus some empty "ablative fuel tanks" (he let some empty tanks absorb the heat and blow up).  No retroburn.

My reentry method was a 1500ms retro burn right at atmospheric entry.

Full album here (45 images, I think):  https://imgur.com/a/2mQ7E0h

Highlights:

I had to do lots of fuel transfers, sometimes during burn, to make this whole thing work.  Here I'm transferring from the orange to the black tanks right after achieving orbit.

I had some troubles with lost orbit lines, and plenty of troubles with decaying orbit around the Mun.  I found my decaying orbit issues were happening when below 9000m ASL, so I established orbit above that line

I was kind of busy with the landing itself, and didn't take any screenshots during that phase.  Then I landed in the dark.  Time warped forward until sunrise.

Val did EVA, planted a flag, and returned to the capsule.  I did one more fuel transfer from the tanks below the green line to those above the line.

I also don't have any screenshots of the ascent.  I did a direct ascent (did not establish Munar orbit but burned continuously from Munar liftoff until I had established an exit from the Munar SOI and a good Kerbin orbit with Pe in the very upper atmosphere.

Right as I was entering the Kerbin atmosphere, I burned all remaining fuel (about 1500m/s of dV).  Here's a shot right after that burn completed.

All 4 of the lateral tanks overheated, and 2 of them blew up.  After the heat effects subsided, I separated the capsule, and the rest of the landing was "nominal".




 

Mission Complete!