Reliable space tugs....

[LostElement]

I am trying to make a space tug/ferry for my Mun/Minmus base. But I always end up with the Spider Like design. It's a bit heavy and oddly hard to get into orbit even though I have sent things 10 times the weight and size. Can someone show me some of their great space tug designs and maybe the craft file?

Thanks!

[magnemoe]

Do it simple, 1.25 m probe core with docking port in front. a 720 or 1440 liter fuel tank, two radial mounted 45 to 90 liter tanks as far forward as possible with two LV-N behind. Remember fuel piping, RCS with monoprop tanks, two of the radial 150 liters are nice. Power either solar or an RTG, battery anyway. and 2.5 meter sas module, they are lighter than the 1.25 meter ones.

you might also want to add an docking port in back with the 1440 liter tank. optionaly senior docking port if you prefer them.

REMEMBER to disable cross-feed in docking port, if not the tug will drain fuel from your lander. Optionaly add an flat structual panel below the port as it don't do automatic crossfeed.

You can also use this as first stage then going to Eve or Duna, burn until just outside Minmus orbit, undock and continue the burn with the ship, do an aerobrake with the tug to get it back to LKO.

[Heavens]

Well the "spider design" makes it easier to land. Depending on what you're planning to transport you can attach the tanks/engines directly to the main tank instead of using girders.

Might need a bit more information on what you want to tug around and also what mods you're using if any as some mods provide parts that make it easier.

This is a heavy duty version I use sometimes (I use different parts but it's basically the same)(30t):

(click for a larger version on imgur.com)

As you can see it has fuel for around 7m 40s burn in vacuum it has a low TWR though so you might not get things down to Kerbin with it.

I mostly use it if I'm not sure about how much fuel I'm actually going to need and am too tired to do some tests or calculations. If it's too heavy you can just use the smaller version of the tanks

Lighter version (14t):

I got a docking port on the bottom just in case I'm trying to pull something with a port off the ground, I've only manage to get it done once so far. You can change the remote guidance for a crew pod and add ladders to get your kerbins inside but the 4 engine design gets kinda tight.

You can also reduce the weight by using smaller RCS tanks and drop the SAS but there more or less placeholders to make room to attach things. If you're good at landing you can also reduce to engines to 3 or 2 but I like having at least 3 as it makes it more stable for me.

Hope I could help

Btw. feel free to make suggestions to my designs, I usually just throw them together and not really improve them if the work.

Edited October 8, 2013 by Heavens