Explorer III - or there and back again.

[Scarecrow88]

This craft came out of my first attempt at going to Duna, which left my Kerbals stranded there due to a severe shortage of fuel. A quick redesign resulted in Explorer III, which successfully took off from Kerbin, flew to Duna, put 2 Kerbals on the surface to plant their flag, brought them back up to the orbiting command craft, which then brought all 3 safely back to Duna.

Following that mission, I then decided to see just what the craft was capable of and have so far sent it to to land on Ike, Dres, 3 of Jool's moons, Laythe, Pol and Vall, Eve's moon Gilly, and out to Eeloo. In each case the lander put two Kerbals on the surface, and then all three Kerbals have returned to Kerbin.

Action groups:

3 to toggle the solar panels

4 to toggle the ladders on the lander

I know it seems like a strange choice, but these just happen to be the default keys for those functions that I use on all my craft.

Notes:

The lander is fitted with drogue chutes to help with landing on Laythe and Duna. If you are going to a moon or planet with no atmosphere, feel free to remove them to save some weight. All the missions I flew were done with the chutes on board, so it's not an issue to leave them

The craft uses a lander for excursions to the surface, leaving a command ship in orbit. Therefore you need to be able to rendezvous and dock to use it successfully.

To save weight, the lander is not fitted with RCS, which is instead fitted to the command module. Once you get the lander back close enough for docking, you should change ships and perform the final docking with the command ship.

Once the lander has returned to the command ship, any fuel remaining in the lander should be transferred before ditching the lander. This just gives an extra safety margin to the returning vehicle.

You shouldn't have problems with fuel supply on the lander, but if you need to save weight getting back in to orbit, the external tanks can be ditched once they are empty. However, don't do this before landing, as the legs are attached to them.

Whilst the craft has enough fuel to visit and return from the bodies mentioned, it still pays not to waste it by transferring outside optimal transfer windows.

If you do happen to find yourself getting low on the return trip, you can always rely on aerocapture at Kerbin.

Downsides:

This design does use a big asparagus stage for the initial launch, so the first few tanks become empty fairly quickly after launch, so be ready to drop them. Despite the large number of tanks at launch, it is stable.

If you don't like leaving debris out there, I'm afraid this is not a design for you, as it does tend to shed quite a bit.

After the initial ejection burn, which uses a skipper on the second stage, most of the interplanetary transfer uses the nuke engine, so be prepared for longer burn times.

Pictures:

After dumping the launch and second stages, this is what you are left with.

Laythe

Vall

Pol

Dres

Gilly

Eeloo

And this is all you are left with when you start heading back to Kerbin, and most of that gets dumped once you are sub-orbital!

You can download the craft file here: Explorer III

Edited August 21, 2013 by Scarecrow88