Full (almost) Kerbol System Explorer

[sdrevik]

So, I wanted to make an 'all in one' tug/explorer (vanilla parts) to export almost all of the Kerbol system.   Criteria was that as much of the ship as possible should be reusable at each stop, and it can refuel itself along the way.

My plan was to have three main components:  a driller (for refueling), a science lander, and a tug to transport the other two components.   The driller was pretty simple, with a 4500 ore capacity:

Note the large docking port atop, that will mate to the 'back' of the tug.

The harder part was building a lander.   I started a lander that would handle MOST of the standard planets (Mun, Eeloo, etc) a single stage land/takeoff that would have about 3000+ dV.   Added chutes and drogues for Duna and Laythe.   For Duna and Laythe, I added a removable inflatable heat shield, connected with a docking port so I could add or remove it as the mission required via a docking port:

Experimenting with the inflatable shield was VERY interesting.   A few lessons:

1. If you inflate it and it touches an atmosphere, you can't deflate and re-use it.  Which means I'd need to bring one for Duna and one for Laythe.
2. When you deflate it, it *VIOLENTLY* explodes.   So I separated it as much as I could, and experimented to make sure after the peak of re-entry heat, I could turn the ship prograde, drop the shield, and then flip back retrograde before finishing the landing sequence (in some cases just turning sideways and firing the engines to get the heck away from this giant bomb I'm carrying).  Otherwise, the air resistance forces the shield back into the craft, with another BIG BOOM.   

So, that being said, my tests with Laythe still didn't work because of the high dV needed to push through the atmosphere.   So, I added another optional stage I could also add with a docking port:

It's super ugly, and the lower engines gimbal way more than they should, making it a difficult craft to control.   But I get an extra 1630 dV from the lower stage, coupled with 3670 on the upper stage (if I use the drop tanks, but a bit less otherwise), gives me about 5300+ dV total, enough to land and take off from Laythe and Tylo.   Note that I have to cut the fuel cross-feed (otherwise it robs the upper tanks first) and the stage cutover is a manual redocking/staging sequence, but not too awful.  

So, now I have all the planets covered, except for Eve, of course.

So, here is the assembled tug, powered by a dozen nuke engines:

Note the two 'extra' sections being carried:
- Fuel/Engine set for Tylo
- Thermal balloon for Duna
- Another set of both for Laythe

And, of course, a science lab.   Fully assembled and fueled, she has about 5000dV.    Getting ready to run the full system test!

Edited January 11, 2018 by sdrevik

[MacLeod-Industries]

Love the use of the inline cupola.

Very creative.

You do know you can turn the vector engine gimbal down, right? It is almost always too excessive when I use it.

Edited January 12, 2018 by MacLeod-Industries

[sdrevik]

Thanks, I thought you could only turn it on/off, but I'll recheck for an adjustment, maybe added in 1.2 or something.   I realized that once I stopped all the crossfeeds, I only have about 3400 dV (if I don't use the fuel in the lander, driller, or supplemental stages.... which I could, as long as I refuel them later).   So I'm heading to Eeloo now with just enough dV without dipping into reserves.

[sdrevik]

DESIGN ISSUE #1: did a test refuel at Minmus, found one problem- the '125' converter is 10% of the conversion efficiency of the '250', so I need to be using the '250'.  No problem, being modular with giant docking ports, I made another new module, moved it to Minmus, and docked it in the back.   

Still, at Minmus, it took five refueling runs to top off the tank.   Thank goodness for MechJeb rendezvous and docking autopilots.

And then down to Dres:

Now, where to next?  What's the best transfer?  Out to Eeloo?  Or into Jool to test my Laythe and Tylo stages?

DESIGN ISSUE#2:  Should have put a relay antenna on the driller, as I use an engineer, and he doesn't know how to fly if not in LOS of Kerbin with the big antenna.  For now, I will have to be careful about which side of planet he is on when landing and doing rendezvous.   A pain, but not an insurmountable obstacle.

Edited January 16, 2018 by sdrevik

[sdrevik]

Update:

Got to Jool, did a refuel from Bop, but it's clear the driller is a little small... it would take about 5 trips.  So, I've decided on each mission, I must manually refuel once, but then I will use HyperEdit to finish the fueling to avoid sheer boredom.

Then we pull off the lander and our first boost stage/inflatable shield and carefully dock the two.

After refueling, we pull into Laythe to try out our boost stage / inflatable shield plan.   It works great, we re-enter, when the parachutes deploy, we were able to drop of the shield, chutes get us down to about 20m/s, and the engines do the rest right before landing.

 

Takeoff successful, including manual drop of the lower stage via undock, managed to get to a 250x250 orbit (I wasted a lot of fuel coming down from a higher orbit, so the 'tug' had to come down to get me.

 

THAT's where things started to get a little crazy on the tug.... (to be continued)

Edited February 3, 2018 by sdrevik

[sdrevik]

Because my tug now had a big fuel tank on one side and not on the other, it was unbalanced.  I tried shifting the fuel, but that wasn't enough.  I tried cutting the throttle to 10%, but that made intercepts difficult to time.    So, what to do?

I undocked it and mounted it temporarily to the front of the ship.   Then, once I intercept the lander, I'll put the lander back on first, and then the extra fuel/shield assembly behind it, and fly to my next destination, Tylo.   Once I'm done with Tylo, I just have to carry around the shield (for Duna), which shouldn't throw the balance off too much.   However, if that shield tumbles around, it's going to be hell to dock the tug with it!!!!

 

Edited February 3, 2018 by sdrevik