Looked like a fun challenge, and I had never built a duna plane before, so I did! Its called 'Mupyiba', or 'massive nuclear powered flying wing with a bunch of lawnchairs strapped to it' Its powered by a single fission reactor from near future, which gives it unlimited flying time and 240 e/s to work with. That powers 6 small electric propellers plus one larger one, giving it decent thrust even on duna. The rest of the plane is just lifting surface. Getting this to duna, howerver, was interesting. I originally had all these ideas for assembling it in space, or making it fold up using infernal robotics. Instead, I just strapped a bunch of mainsails to it and blasted it into orbit. This worked surprisingly well, and ended up in orbit with quite a bit of fuel left in those tanks. Next launch was the crew transport vehicle, with an equally silly ring of boosters. TWR of like 4. The idea was that moving 20 kerbals is way easier in microgravity than, well, I actually dont know how else I would have done it. Now, I had planned for a third launch to send up a transfer stage with NERVAs to get it out to duna, but I ended up with enough fuel from these to launches that I just jettisoned two of the boosters, and used the fuel from the crew transporter to get it to duna. Luckily mainsails have enough thrust vectoring to deal with the offset mass. Other than that, it was a typical transfer to duna. Now, landing on duna wasnt so bad. I just skimmed over the atmosphere until I made a landing moving at about 120 meters/sec. It took a few tries before I found a flat enough location, but I did at 4000 meters elevation. Taking off again was a bit more difficult, and eventually I had to leave 6 kerbals behind. Those little guys weigh wayyy more than I realized. After a few uh, simulated takeoffs, I got it into the air with 10+1 kerbals, and once I get in the air, I can stay there indefinitely. Without any kerbals on board, I could fly at over 8000 meters, but with all 10, I could only maintain 7000. These guys are enjoying the view, and wondering what voodoo is keeping this thing in the air when the sensor reads 'VACUUM'. So, lemme try to add this up. 1 for using FAR, 1 for circumnavigation, 2 for 2000 over 5000, and +9 for my 11 kerbals. I think thats everything. I may go back and make a larger one with 2 nukes and 14 engines, and see how many kerbals I can fit on it. This one can hold 19, but taking off was almost impossible and I couldnt maintain anything over 5000 altitude. I agree that the fission reactors are very powerful, but they are also very heavy. That one reactor is more that half the mass of the entire structure. More importantly, I could get the same performance out of lots of solar panels mass per e/s wise, but the lag on them would kill me. You can see the rest of the pictures here- http://imgur.com/a/LVSoR A few shots of the orbital stuff, some explosions, and thats about it. This is the first challenge that I have tried to do so far, and it was great fun, thanks!