The Jool-Diver Challenge: Return from Jool's Lower Atmosphere!

[Beriev]

Hello all.

I recently returned Jebediah Kerman from sea level at Jool's North Pole (linked here), and decided to throw down the gauntlet for others to attempt, too, as there is quite the disappointing lack of return missions from Jool's lower atmosphere. 

(Credit where credit is due - the format used is very heavily based on the Jool 5 Challenge)

THE CHALLENGE

Tier 1: Get at least 1 kerbal below 120 km on Jool and return. (120km is the "upper atmosphere" threshold)

Tier 2: Get at least 1 kerbal below 0 m on Jool and return to Kerbin. (Crush limit is at -250m)

Anybody who completes

Additionally, for both tiers, I'll include a tag on submissions competing to minimize mass, cost, or part count ("[LOW MASS-#mT]", "[LOW COST-$#]", and "[LOW PARTS-#]", respectively, with "#" being the value of interest), meaning that there will be 6 possible first places at any time. If there is enough traffic, I will make each tier's sub-challenges a separate leaderboard.

Note that I will accept retroactive submissions, so if you've done it before I posted this challenge, feel free to make a submission. I also will accept submissions that complete this challenge alongside other challenges, like the Jool 5 mission or a Grand Tour.

RULES

1. No cheating, like using the debug menu, HyperEdit, config editing, or persistence file editing.
2. No part-clipping of functional parts. Non-functional parts, like wings, heat shields, or structural parts, can be clipped, however.
3. All kerbals must return safely to Kerbin.
4. DLCs and "parts mods" (like Bluedog Design Bureau or DMagic Orbital Science) are permitted, though I will add tags ("[MH]", "[BG]", and/or "[MODDED]", respectively).
   1. Quality-of-Life mods (like MechJeb or clouds) are effectively considered stock ("[STOCK]")
   2. Mods that affect the game itself (like Kerbalism or SCANSat) are considered modded, as well.
   3. "Cheaty" propulsion mods (like OPT or late-game KSP-IE), are forbidden. If you have to ask if it's allowed, the answer is likely "no".
5. When making a submission, make the whole mission easily accessible, like through an Imgur album, YouTube video, mission report, or directly attaching the images in the submission.

THE WALL OF FAME

• Tier 1
  • @king of nowhere (Forum Post) Attached an extra rocket stage to their Laythe spaceplane to get enough Delta-V to return to Jool orbit. Employed several aero-brakings to get into low Jool orbit while completing the Jool 5 challenge. Dipped to a low altitude of 116km (and got an EVA report at 500 m/s!) before racing back into Jool orbit. Quite a unique design at this time.
• Tier 2
  • @Beriev (Album) [STOCK] Launched a relatively large mothership directly into a Jool transfer, and used successive aero-brakings to get into a polar Jool orbit. Used a dedicated lander to get Jebediah Kerman to -203m at Jool's North Pole with a full scientific suite, and then used a separate rotor with a Stayputnik bearing to ascend above 100km before lighting the engines to return into Jool orbit. Tight fuel budgets led to a longer trip home (7yr), but successfully returned to Kerbin in a mini-glider. Not super-optimized, but a nice starting point and a good reference.

FEEDBACK

Any feedback would be strongly appreciated. Enjoy your day!

Edited April 10, 2021 by Beriev

[king of nowhere]

When undertaking the jool 5 jeb level challenge, i sent a ship inside jool to get science from the lower atmosphere, so it qualifies (Part 4A, the linked youtube video). Includes getting the kerbal out of the cockpit to get a crew report

 

Edited April 10, 2021 by king of nowhere