Munshot w/Demo

[WhenYourFuelTanksDon'tWork]

Hello,

Any tips on getting to the mun and back with the demo? I do plan on getting the full game after Christmas, I just want to bide my time slinging kerbals to the mun and back.

[Snark]

Welcome to the forums!

I'm afraid I can't offer super specific advice, as I've never seen the demo, but I can give you a piece of general advice that works pretty well for just about everything in KSP: just try it and see!

There's a high likelihood of comical failure, but that's a big part of the fun. If you get stuck, then come back to the forum, post a screenshot of your ship, explain the problem you're having, and be prepared to receive tons of helpful advice.

Have you successfully gotten to orbit yet?

Edited December 19, 2015 by Snark

[Plusck]

Getting back from the Mun in the demo? No. Can't help you there. The best I've managed is standing on the Mun with maybe enough fuel to get halfway into orbit before crashing.

Sadly, I can't find my original demo install, so I can't even see what I used to get there. I tried loading it up again but the only save I have is too cash-strapped to build a decent rocket.

For the general pointers though:

1) Asparagus. Since your parts are extremely limited in the demo, you really have to asparagus everything. Your lander needs to have drop tanks so that when you are near to the surface, you have at least one full fuel tank in line with your ship and the other empty fuel tanks are busy exploding on the surface.

2) Booster thrust levels. Make them count. You only have one real booster (the flea is never useful when you have anything better, in my experience). From memory at least two stages of two boosters are a good mix, but vary their thrust so that the first ones burn out and can be dropped while the second set is still helping to lift your liquid fuel up to where it can make a difference.

3) Forget what isn't useful. The only rocket available is the Reliant, which provides zero directional control. You may be tempted to try RCS to help in the landing. By all means try it (when you get the full game, you'll appreciate the experience with RCS) but if you want to get back from the Mun, any RCS capabilities are just adding mass. Instead, learn to economise on the energy your pod's reaction wheels need to run.

[Wanderfound]

To get to the Mun:

* Get into a 100x100km equatorial prograde Kerbin orbit.

* Wait for Munrise.

* Burn prograde at maximum throttle as soon as you see the Mun. Keep burning until your apoapsis reaches the Mun's altitude. You should now have a Munar encounter.

* When you're halfway there, go to map view and double-click on the Mun to focus your view there. You should be able to see your future trajectory at Munar periapsis.

* Bring up the navball and experiment with giving very, very small puffs of thrust (minimal throttle, quickly cancelled) in various directions. Watch your Munar periapsis to see how it responds to this. Use this to bring your Munar periapsis down to about 20km.

* When you get to the Mun, burn retrograde at periapsis to capture and circularise your orbit.

 

To land on the Mun:

* Start with a small burn on the dark side of the Mun. Lower your periapsis to 10km.

* Pick a landing spot on the light side of the Mun. As you approach it, point retrograde and light the engines.

* The aim is to bring yourself to a complete halt a few hundred metres off the ground (as you get better, you can shrink this to a few dozen metres). If you're dropping too fast, aim your nose a little above retrograde. If you look like you'll come to a stop too high up, aim a little below retrograde.

* Once you've stopped, drop the last bit vertically. Point retrograde, use as little thrust as possible to control your speed as you descend. Aim to touch down at below 1m/s.

* A fast drop with a quick burst of full thrust at the last moment is the most fuel efficient way to do it. However, it's also the hardest to get right. Either make friends with the quicksave/quickload feature, or accept that you'll waste some fuel to gradually control the speed as you descend.

 

To take off from the Mun:

* Full throttle, tip yourself to just above the horizon and facing east immediately after takeoff. Pitch up just enough to avoid crashing into the ground. Cut the engines once your apoapsis reaches 10km, then circularise at apoapsis.

 

To return from the Mun:

* Point prograde and light the rockets when your ship is positioned directly between Kerbin and the Mun (assuming you're in a prograde orbit, which you will be if you launched eastwards). Cut the throttle when your Kerbin periapsis gets to 35km.

* Dump everything except the capsule just before reentry, then ride the heatshield down. Don't open your parachute until you're safely subsonic.

Edited December 19, 2015 by Wanderfound

[Pecan]

Wanderfound told you what to do, below is a ship to do it with.  Explanation at http://forum.kerbalspaceprogram.com/index.php?/topic/117782-how-can-i-orbit-kerbin-and-the-moon-in-demo/&do=findComment&comment=2109334

This can land on and return from either of Kerbin's moons.  Note that it is much easier to do Minmus than Mun, because it has lower gravity and more flat areas.

Edited December 19, 2015 by Pecan

[Plusck]

Awesomely overdone rocket there

But Minmus isn't in the demo, AFAIK. Kerbin and Mun are all alone.

[cantab]

Nope, the latest demo includes Minmus.

If you want to do flybys and orbits, it's relatively simple. Get into orbit with a decent amount of fuel in your ship, then set up the manouvre nodes and burn them. Just remember the demo lacks control options, you might need to spam the little reaction wheels on your launchers to keep control in the ascent to Kerbin orbit. (The full game has engines with thrust vectoring which makes things a lot easier).

When you want to land the big problem in the 1.0 demo is picking a lander engine. The Reliant is heavy, but gives you the ability to throttle which will make the landing itself relatively easy. Your alternative is to use the RCS thrusters and monopropellant. Try 12 thrusters, that should do it. That will let you make a *much* lighter lander which is easier to get to the Mun in the first place but you have no throttle so you'll have to be tapping H (for forward RCS thrust) to control your landing which is tricky.

[Pecan]

12 hours ago, Plusck said:

Awesomely overdone rocket there

But Minmus isn't in the demo, AFAIK. Kerbin and Mun are all alone.

As cantab said, the demo now include Minmus as well as Mun, Kerbin and the sun.
What is it that you think is overdone on the rocket?  I am keen to see alternatives - tutorials and tools for absolute beginners are my thing - but no-one has ever offered any other that could launch, go to either moon, land and return safely.

For those that don't have the demo (and can't be bothered to get it), you should be aware that the aerodynamics are from 1.0.1, so a little different from 1.0.5 - especially heat.  These are all the parts available:

• mk1 command pod
• stayputnik
• FL-T100 and FL-T200 LFO tanks
• Fuel ducts
• Stratus-V monopropellant tank
• LV-T30 LFO engine (no gimbal)
• RT-5 and -10 SRBs
• RCS thruster block, small inline reaction wheel
• Srruts, modular girder, launch clamp
• TR-18A stack and TT-38K radial decouplers
• Nosecone, AV-T1 winglet
• LT-1 legs, mk16 parachute, OX-4L solar panels, Pegasus 1 ladder, Z-100 battery
• communotron 16, mystery goo and science jr.

cantab's suggestion for an RCS-lander is interesting but MJ and KER don't like telling me RCS dV and TWR so I'd have to work it out by hand - perish the thought!  It's going to be difficult to place the thrusters and radial monopropellant tanks needed, I would think, unless you keep an empty LFO tank just to give you some structure.  In any case, you'll presumably still need the T30 for transfer to the moon of your choice anyway.

[Plusck]

8 hours ago, Pecan said:

As cantab said, the demo now include Minmus as well as Mun, Kerbin and the sun.
What is it that you think is overdone on the rocket?  I am keen to see alternatives - tutorials and tools for absolute beginners are my thing - but no-one has ever offered any other that could launch, go to either moon, land and return safely.

Oh, it wasn't a criticism.

As I said, in the demo I only ever got TO the Mun, never back off it. So my builds in the demo were never quite as huge as that. They tended to be much more lie Weywot8's picture in the thread you linked to.

And I'd forgotten Minmus was in the demo since I'd more recently gone back to my ancient demo version from 2013.

So... I went back and tried Minmus again, and it would have worked out if I hadn't been impatient and botched the transfer to Minmus. So in fact I only go back to Kerbin orbit, and not low enough to get back on the ground.

This was the ship - guaranteed able to get to Minmus and back if you don't mess it up

 

Edited December 20, 2015 by Plusck

[Pecan]

2 hours ago, Plusck said:

Oh, it wasn't a criticism...

This was the ship - guaranteed able to get to Minmus and back if you don't mess it up

Excellent, criticism is welcome, exemplars even better :-)
So this does Minmus return landings?  I'll give it a go.  Not getting a low enough Pe to re-enter is only a matter of tweak and there's always the GOAP option.

I must admit I never designed anything specifically for Minmus but a demonstration vehicle that can do that but not Mun would help emphasise to beginners that Minmus is the easier/better first choice, despite being harder to get to.

ETA: Trying to build from the picture I see no radial decouplers.  Am I right in thinking the side-stacks are fixed and this SSTOs?

Edited December 20, 2015 by Pecan

[Plusck]

In fact, from the pic there of me sitting on the ground at Minmus, I actually should have (maybe) got all the way back but I forgot that I designed the landing-leg tanks to be droppable. So I took them back to eternal Kerbin orbit too...

Facepalm etc.

This was the April / May 2015 demo. And this should be the correct craft file for the ship.

Edited December 21, 2015 by Plusck

[Plusck]

Oh - so I forgot you can't load craft into the demo...

OK, well it's parachute, pod with batteries, stack separator, fuel tank with solar panels, two decouplers with the fuel tank and another beneath that with landing legs + fuel line

Then in the middle it's four tanks, set of 4 fins, reliant, decouplers in 2x symmetry both ways, 4 fuel tanks + reliant on each side, asparagus lines, and SRB set at 54% (I think) boost with one and a half tanks above, asparagus lines to the side tanks.

I say one and a half because I think that I changed that just before setting off.

So yes, it was supposed to be droppable tanks on takeoff.

Ascent profile: aggressive. Full power start, turn a few degrees right off the launchpad. Enable prograde SAS. Thrust down to 2/3 at about 140m/s until the SRBs are dropped. The speed will still pick up to well over 200m/s by then. Then correct angle to about 50-60° while throttling up to 100%. Keep prograde assist on but keep pushing it down towards the horizon if it doesnt go on its own. You should be able to get up to 70km with some of the main stage left, with 800m/s or so circularisation still to go on the final stage. I'm sure it could be done better still, maybe even enough to get off the Mun...

 

 

Edited December 21, 2015 by Plusck