Guide: VTOL SSTOs lazy trip to the Mun (KSP)

The Whynaught VTOL SSTO (now with extra droptank!)

I was asked about this in comments here (@sexysharkattack) about a VTOL SSTO I had made so here's a guide to making them.

SSA over there asked if it could reach the Mun - I wasn't sure, so I added a droptank (so it should carry enough fuel) and a second crew pod (so it could perform the useful function of rescuing kerbals as far away as the Mun) and decided to try it!

Firstly let's go through how to make those engines - they're odd and really the only clever part of this design.

Building the Engines

Whee!

Seriously though, I'd better land before I drain any fuel from that back fuel tank and start to have a bad time. I should've used something else for weight in this example.

Back to the real trip with the real plane!

Orbit Already?

The flight up was hairy and it seems I didn't take a single screenshot during the climb - this shot is after I've already circularized my orbit. My ineptitude or at least lack of effort here was to blame for nearly all of it.

1: Takeoff needed close attention as the TurboJet engines could barely lift all this added weight on their own.
2: I wasn't really paying attention and overshot altitude higher than I'd intended, reaching 30km without enough speed, dropping down to 26km while gaining speed, then climbing again.
3: I got bored at about 28km, pitched up and turned on the LV-N nuclear engines. This may have been lucky, as I'd screwed up the fuel-flow and the back tanks were starting to empty before the front ones - this may have made the plane uncontrollable or at least much less stable if I hadn't done this (I should've really gone back and fixed it in the hangar).
4: I underestimated how long it'd take me to circularize with the lower speeds I'd reached in atmosphere, and wasted a bunch of time and fuel altitude holding past apoapsis.

Altogether I used a lot more fuel than I needed to, and that would come back to bite me after not long. Not long at all. I should've reflown it or landed to try again, but you may have noticed I wasn't feeling like running this mission again by now :)

Burning to the Mun

It's worth noting that I kept the droptank well past when I needed to. I did drop it while at the Mun (before circularizing an orbit to pick a landing spot, because apparently I need to keep using lots of extra fuel all the time).

Landed!

I miss the droptank already, and I may have overshot the landing zone by a little and (believe it or not, I hadn't noticed the pattern here yet, bonus points if you can spot it!) burned up some extra fuel in order to (just) not fall into a crater - I'm teetering on two legs here (that was a little closer than I'd intended.. but acceptable, there's no real danger).

You can see the docking port here for this utility vehicles secondary purpose (it's a tug! Hook it to a tank/spacecraft/station in orbit and you've got some good range with this thing!)

Time to go!

It's at this point I started to worry a little about my fuel. I launched on a very shallow angle to the other side of the mun to make my burn...

Somewhere about here?

Can you guess what's going to happen yet?

I missed it.

This path is suboptimal and I'm starting to need optimal.
So I do the only thing I could - burn some extra fuel (surprise!) to circularize munar orbit and avoid any mountains happy to hand out free dV in the wrong direction, then wait to come around again.

Much better.

This burn was at an earlier time in the orbit, but I still had to make the poor kerbal wait a couple days to complete an orbit to reach the optimal spot for a burn.

Out of Fuel in the main engines!

Who could've seen that coming, and with the periapsis at 350km it's still not low enough.

I now pay for my laziness in all the other stages by having to use the "universal plan B" (a couple of monoprop tanks I brought combined with a tired finger over the next couple of minutes from holding the thrust on).

Success!

I pick an altitude which will allow me to aerobrake nicely and pick a landing to KSC (by raising the periapsis back up with monoprop when I come out of the atmosphere again) when I realise I haven't tested ditching in this thing yet and I'm heading towards water. It's too late to keep myself in atmosphere by the time I decide not to go to KSC, so I have to go around the planet one last orbit.

Nailed the landing!

Go Agonarch! You hit an ocean that you happened to be near anyway! Nice job!

*self-five*

What did I learn?

-I am significantly better at this game when I'm paying proper attention compared to when I'm not.
-This SSTO is more than capable of making it to Mun and back, in spite of my flying of it in this regard. Other than the "front tanks draining first" thing it's also really controllable.
-This thing flies horribly when completely empty (it isn't usually used for this kind of thing, and without the weight in the liquid-fuel tank in its body the CofG moves to a funny place).
-Screwing up is still quite a lot of fun (fixing it is, at least).
-If you have a specific task in mind, maybe make a specific vehicle to do it and don't just strap fuel to your utility tow vehicle to see if it works. Or do, this was actually fairly entertaining. In fact, do and let me know.
-I could lower those engines with offset mode now it's available to give me more clearance below the aircraft then put the lander-can down there. That should provide a much lower centre of gravity without making too deep of a hole between the legs (so docking for tugging would still be easy enough).
-Using the new navassist stuff - in this case a retrograde heading to do a lazier mun landing (there's that pattern again) uses a lot more fuel than stabilised or manual control as it shakes all over the place.

In spite of how it may seem I did want to do this mission and I did enjoy it!

If you've got this far and you're looking for more KSP stuff I don't have much yet, but check out this guy if you're interested in KSP in general or rocket history/space history:
http://www.ksphistory.com/
It's made/managed/done by an imgurian/redditor! @mendahu

This guy does tutorials of various kinds as well as a lot of builds, I learned a lot of heavier (as in high mass) spaceplane stuff by blatantly ripping off his designs initially so I think it's worth a look.
http://ksp.fragmentedpoe.com/
And he's also an imgurian! @fragmentedpoe