Double Mun challenge entry - All rockets all the time

[purpleivan]

This mission report details an entry to The Incredible Double Mun Double Kerbin Landing Challenge in which a a brave crew of three Kerbals was launched from Kerbin, flew to and landed on Mun, then returned to surface of Kerbin, only to head off for another Mun landing and finally returned home to Kerbin again. The vehicle at launch from Kerbin weighed 684 tons.

The album of images for this mission are here.

Here is a listing of the phases of the mission.

1. Launch from Kerbin
2. Once in a 79km orbit the Mun package (a Mun transfer vehicle and a Mun lander) were separated from the Kerbin lander vehicle that was to remain in Kerbin orbit
3. The Mun package travelled to Mun orbit
4. In Mun orbit the Mun lander detached from the descent vehicle and descended to the surface
5. Kerbals ran around having fun and planted a flag
6. The Mun lander returned to Mun orbit and rendezvoused with the transfer vehicle
7. The Mun package returned to Kerbin and using a mixture of aerobraking (about half a dozen passes) and some fuel burning was placed in a 170km orbit
8. Once partially refuelled from the transfer vehicle, the Mun lander rendezvoused with the Kerbin lander and docked inside its cargo bay. Here it was fully refuelled from the lander
9. The Kerbin lander descended to the surface of Kerbin
10. The Kerbin lander ascended to an altitude of 241km, with the Mun lander leaving its cargo bay once above the atmosphere to rendezvous with the transfer vehicle
11. The Mun package returned to Mun orbit
12. The Mun lander visits the Mun surface for a 2^nd time
13. Kerbals had more fun, planted another flag and had ice cream
14. The Mun lander rendezvoused with the transfer vehicle in orbit
15. The Mun packaged departed Mun for Kerbin, with the transfer vehicle burning until its fuel was depleted, then the burn was completed by the detached Mun lander
16. After some more Aerobraking fun and games (only a couple of passed this time) the Mun lander descended for the surface of Kerbin
17. The crew lands on the surface of Kerbin for the last time… and had more ice cream (possibly strawberry, details are sketchy)

 

Overall this mission went pretty smoothly although when I deployed landing gear on the Kerbin lander, those of the Mun lander (that was tucked inside the Kerbin lander) were destroyed. Between launch from the surface of Kerbin and the deployment of the Mun lander high above Kerbin, the remaining leg met the same fate.

I had originally planned to use the Kerbin lander to bring it and the Mun lander in its belly up to an orbit of around 100km and then send a lightly fuelled Mun lander from there up to the higher orbit that the transfer vehicle was parked in. However I realise on the way back from Mun for the first time, that it would be more efficient to fully fuel the Mun lander from the tank that supplied the upper stage of Kerbin lander, then release the Mun Lander once carried above the atmosphere, but not actually into orbit, for it to then burn for the rendezvous. This allowed me to bring about ½ a tank of fuel back to the Mun package, which made the final return burn to Kerbin supplied with plenty of fuel.

Edited September 18, 2016 by purpleivan