Check my flight itinerary for a Laythe landing please.

[Monkeh]

Is this a reasonably acceptable way to get to laythe for a landing, or is there a much more efficient way of doing things?

1) Burn to orbit with my version of a gravity turn

2) Use Mun slingshot to escape kerbin SOI

3) Huge burn to get to Jool SOI

4) Burn retro at Jool periap to be captured

5) Burn retro at periap to lower apoap

6) Warp round to new periap and repeat until orbit closes down

7) Use maneuver node to work out burn to be captured by Laythe

8) Repeat 4 and 5 until got roughly circular orbit above Laythe atmosphere

9) Pick landing point with retro burn

10) Land with parachutes

Is their something I'm missing or doing stupid wrong? I keep running out of fuel in Laythe orbit. I thought I had enough Delta V, but alas not. I've tried a few designs, (Obviously not very good ones), and can't quite get there. I don't need the perfect approach, (do I?), but any pointers as to ways to save some fuel or improve my approach would be greatly appreciated. Laythe looks so nice, I need to land there or forever be a pathetic creature that no-one shall ever love.

Edited August 13, 2013 by Monkeh

[Gauss H2K]

Try aerocapture with either Jool, or Laythe, all it requires is you get your periapsis just dipping into the atmosphere, which will slow you down, and if performed at the correct altitude (I would use quicksave to find it), it will allow you to achieve an orbit with little delta v required. Also when I do reentry burns, I aim to get my periapsis just inside the atmo, and let drag do all the braking. Also if you aren't already using it, I would recommend MechJeb, if you just want to see how your designs work because you're a rubbish pilot, it has functions like an autopilot, if you're a great pilot, it has other features like predicting where you'll land, preventing jet flameouts, and other little things that reduce some of the workload when piloting vessels.

Without refueling, something like only 8000 delta v is needed to go from launchpad to Laythe orbit

[Scorpi15]

I believe that a burning for a mun slingshot and then a jool capture is less efficient than a straight burn out of Kerbin's SoI.

[Flanders]

Try using aerobraking in Jool's atmosphere, if you do it right, you can get an orbit around jool without using hardly any delta V at all.

By carefully choosing aerobraking depth, you can even make the resulting orbit end up with an apoapsis at the same height as Laythe and then just wait a few orbits for an encounter (after raising periapsis out of the Jool atmosphere).

If your timing is right you can even manage a direct capture to Laythe orbit directly after the Jool aerobrake.

To find the correct aerobraking altitude at Jool atmosphere you can either use these charts: A handy chart for Aerocapture at Jool, use trial and error by quicksaving and quickloading, or use the aerobraking calculator included in MechJeb.

And using a Mun assist to escape Kerbin is almost never "cheaper" than doing the burn directly in low Kerbin orbit due to the oberth effect (higher speed lower in gravity well => each m/s Dv spent will affect your orbit more, thus saving you fuel)

Edited August 13, 2013 by Flanders

[Monkeh]

OK, so the aerobrake seems to be the best way to reduce fuel requirements, nice. I'd rather not use MechJeb for now as I'm still learning the ropes when it comes to being a decent pilot.

The craft I was using had around 8500 m/s delta v according to the engineer redux, so it's obviously my own incompetence that is stopping me, as expected.

Must practice this aerobraking witchcraft then I suppose, I have been into the centre of Jool once, that was...weird, so I assume it's slightly tricky to get it just right to slow down a lot without being sucked into the gas giants rather deadly interior?

Cheers though, something to practice

[Scorpi15]

It's better to underestimate, because that gives you quite a bit of margin for error if you go deep enough. You can always burn retro to slow down enough to be captured into a Joolian orbit. Go too deep, however, and you will probably won't make it back out.