MK3, 58 parts, 4 Kerbal, cargobay, dockingport, RCS, no clipping, no lost parts, runway, splashdown, swim-inspection, takeoff, 140k orbit (500m/s spare), deorbit, runway-land, takeoff, coast-water-splashdown, moved-to-coast-using-jets
I created multiple crafts for this challenge but found it hardest using MK3 parts (And I wanted to be the first on this challenge using MK3 ;)) so here is my participation, its called HAMMERTIME, just because... I dont know - it kind of hammers to orbit
My design goal was to make it easy and enjoyable to fly. It took my about 5 hours to design and tune - it could easily be tuned for better lift performance or efficiency but then it would not make so much fun to fly.
The only mod in use was Flight Engineer.
Mass: ~87t (~52t fuel) = 35185 kg dry
Engines: 4 Whiplash, 1 Vector
4 Airplane Wings (MOAR LIFT!!!)
Flight log/profile for this challenge:
Throttle full, SAS on, Turbos on (using 1-key)
Take of between 70 (yes, really) and 100 m/s
Level out at 100m height to reach water
Turn off engines, enable brakes
Touch down on water (undeploy brakes before splashdown!) under 70m/s (it even is possible to land leveled out with under 50m/s)
Do the Vessel inspection (I could not resist doing a group photo of all 4 Kerbals )
Takeoff, engines full throttle, at 70m/s pull up to leave water (easy with so much control surfaces and lift)
Ascent is also easy, this was the part I tuned the most: Just ascent between 10° and 15° and you will reach a height of 20km at about 1000m/s (This craft is more a plane than a spaceship so going faster earlier would burn it)
At a height of 20k enable vector engine (using 2-key) - just let the jets flame out (or disable using 1-key), increase ascent to about 20° until your apoapsis goes to the desired height (I did 85k)
Circularize the orbit. At this point I f**ed up (happy little accident) and did a 144k/140k orbit
At this point I had about 500m/s delta-v still in the tanks - plus LF for the jets. If you are at 75/75 you have 650m/s, so no mun or minmus without refueling. But you can also put 15t of cargo to 85/85k.
The descent is the only tricky part, but it can be archived (with Air-Brakes deployed) following one rule: Keep the vertical speed below 50m/s (at heights between 38.000 and 25.000k meters) using an AOA between 10° and 40° - archiving this can be easier if you pump some fuel to the front. You won't exceed 75% heat (of the 1200K airplane wings, they are the week-point).
If you want to reach KSC from 140k height you need to burn retrograde to an PA at 0m exactly at the opposite to the KSC (From 75/75km burn 50m/s retrograde at the crater).
The challenge says you need to land on KSC runway OR water-land at any coast. I decided to do both - first land (unpowered!) at KSC runway and lift of again to water-land at the coast next to the KSC.
I am quite happy with this universal-easy-to-fly-spaceplane (just KEEP THE VERTICAL SPEED BELOW 50m/s AT DESCENT ), in atmosphere it flies like a big fighter) - I will use it as my new default cargo SSTO.
Album URL: http://imgur.com/a/1eIdg
Craft File: https://drive.google.com/file/d/0B6w6PHP0FfB2bTIxNFBDd2x1U0E/view?usp=sharing