Duna Multi-Cache return

[SirJodelstein]

This is the story of a semi-successful attempt at my own Duna Cache Return Challenge

Mission objective: Return three cache containers from the surface of Duna. The soil samples have been dug out and packed for the trip home in a mission at a previous launch window.

This mission was intented to be a spectacular display of engineering efficiency. To Duna and back in just one launch window, with minimal fuel safety margins. Low cost and no unnecessary parts. The final product was an 80 part rocket that held Launch system, interplanetary drive, rover and return stage. It might have worked. But the engineers forgot an important detail: The atmosphere on Duna is incredibly thin, and flying in it requires way more lift or speed than on Kerbin. They built a glider that could lift off and glide on Kerbin at 30m/s. When the glider arrived on Duna, they were shocked to see that a stable glide could not be achieved under 200m/s, and so the planned soft landing turned into a big explosion.

Game over with a partial success - the return stage landed safely with cutes and thrusters. So much for the single-launch efficiency award.

But the caches had to be returned anyway. So they quickly added two more wings to the rover blueprint and sent another rover in the closing transfer window. But that one also couldn't sustain a landable gliding speed in the thin atmosphere. A last-second lithobrake-on-interplanetary-stage saved the Mk2 rover from a similar fate like its predecessors. The glider was retitled as a rocket driven rover and began to collect the samples. 40m/s drives on the slopes of the steep valley were no problem, and 2 days later all samples were docked at the return stage from the first mission. The rest was easy.

So, it took a little longer (return on Year 2 Day 160 instead of Year 2 Day 37) and at a much higher cost, but it was still a sucess!

Javascript is disabled. View full album