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[Peewee]

tried using the 'preview' button?

Having network issues at the moment, I just want to avoid double posting or getting stuck trying to send the whole post.

[forsaken1111]

tried using the 'preview' button?

Having network issues at the moment, I just want to avoid double posting or getting stuck trying to send the whole post.

Edit post in document instead.

[Peewee]

Meh. It's done now anyway. Maybe I should set up another one to show how to slow down using the same setup...
Good grief that took me an hour?! Bleh.

[alway]

As a side note, repeated gravity slingshotting is how we sent the voyager probes out of the solar system. http://en.wikipedia.org/w/index.php?title=File:Voyager_2_velocity_vs_distance_from_sun.svg&page=1

[LoSboccacc]

Please do I can't wrap my head on how to enter/exit soi to slow down

Also: can't all these tiny tibids of tutorials/explanations/examples be added or linked in the opening post?

[Putnam]

Please do I can't wrap my head on how to enter/exit soi to slow down

Also: can't all these tiny tibids of tutorials/explanations/examples be added or linked in the opening post?

There are a bunch of helpful tutorials in-game.

[ank]

Please do I can't wrap my head on how to enter/exit soi to slow down

Also: can't all these tiny tibids of tutorials/explanations/examples be added or linked in the opening post?

Just approach from behind the planet to slow down.

[Rex_Nex]

After spending some time doing the two tutorials, I got a lot better. I feel smarter too!

Managed to make my first mun landing soon after. It's very easy once you know how to control your orbital ring. Just throw the ring out there a good 45 degrees ahead of the moon, wait until you hit the SoI, burn retrograde until you go from slingshotting past it to orbiting it, then bring down your orbital ring so it intersects the light side of the mun! So simple, even a human could do it!

I swear, half the issue was learning what those things meant, but once I did it turned out what looked really complex was really just putting on the thrust when you get near certain symbols on the map/navball.

Edit:

Quick question; what's the most fuel efficient way to get into orbit? What I've been doing is shooting straight upwards until I'm out of the atmosphere, then prograding when I get to the periapsis. It seems to guzzle a ton of fuel and the periapsis quickly moves away...

[LoSboccacc]

http://imgur.com/a/8s5le#15

I'm amused on how other people can manage to change planet starting with that little fuel.

I used 3*4*3 3mt double tanks to get a lander in position for Duna.... 

[ank]

Edit:

Quick question; what's the most fuel efficient way to get into orbit? What I've been doing is shooting straight upwards until I'm out of the atmosphere, then prograding when I get to the periapsis. It seems to guzzle a ton of fuel and the periapsis quickly moves away...

Oh man, we had several pages discussing this:
For the most efficient launch to orbit you have to:
Burn max until you reach about 200m/s. (this is the optimal tradeoff between gravity drag and air resistance)
Then throttle down to about 20%.
Then slowly throttle up while gravity turning towards 90 degrees(in case you want to transfer to a planet further out than Kerbal, if you want to go closer to the sun, pick 270 degrees.

Gravity turning means using gravity to turn the craft from straight up to the horizon.
Then burn prograde until you have an orbit, as you already know.

The most efficient fuel to thrust ration is having your craft barely moving at launch, then faster and faster as the ship drops weight.

Thanks to LoSboccacc!
I would never have realized the truth of the things I just posted, without your persistence in the face of my stupidity

[Peewee]

Please do I can't wrap my head on how to enter/exit soi to slow down

You have to be going at least close to the same speed as the planet you're slingshotting around, because you have to catch up to it in order to exit at the correct angle.

Sorry, couldn't be bothered to MSpaint some figures with the vectors and everything, have some screenshots instead.
http://imgur.com/a/tVqMF
1. Setting up an encounter... The purple orbit here is pretty close to the craft's, because it only barely enters Duna's SoI. (note the PE above Kerbin orbit, and the AP significantly higher than Duna orbit)
2. Getting closer and adjusting the orbit (only needed to spend ~50 m/s here)
3. Periapsis = 49km? Close enough! I would have preferred going a little lower, but then I'd have risked losing significant momentum to Duna's atmosphere.
4. Showing the angles relative to Duna's orbit
5. Post-slingshot orbit (several years later because I forgot to take a picture immediately, and I was trying to see if it would ever get close enough to Kerbin to send it home)
Note that the AP has moved down to almost exactly Duna's orbit, and the PE has moved down below Kerbin orbit.

[LoSboccacc]

Then slowly throttle up while gravity turning towards 90 degrees(in case you want to transfer to a planet further out than Kerbal, if you want to go closer to the sun, pick 270 degrees.

this single point is debatable 

to shoot inward, you can get into the standard 90 deg orbit, and start your escape burn while moving 'inward' the system (that is, if you need to launch at 180* deg in retrograde to reach moho, you can launch at 0 deg in prograde for the same effects)

*making angles up

[Nao]

Quick question; what's the most fuel efficient way to get into orbit? What I've been doing is shooting straight upwards until I'm out of the atmosphere, then prograding when I get to the periapsis. It seems to guzzle a ton of fuel and the periapsis quickly moves away...

I can't find relevant challenge thread in KSP forums for a video and discussion on the topic, I'll just post my way witch is close within 1% of record lowest fuel used to orbit.

1. burn at max thrust (make a craft with take-off thrust to weigh ratio at around 1.3)
2. lower thrust a little (or jettison empty acceleration stage) when reaching 85-100 m/s (not more than 100m/s below 1000m)
3. continue upwards (90deg pitch) to around 8000m and 150-180m/s
4. start turning at around 8500m, do it slowly, so that you don't have more than 70-60deg pitch below 12km-15km or 200-250m/s
5. if you had lowered thrust earlier make sure to be at 100% above 12000m
6. 45deg pitch should be around 20km and 350m/s (roughly - as it depends heavily on craft design, generally less power - stepper initial climb)
7. stop rotation around 30deg and use pitch changes to get 35-50km Apoapsis.
8. at around 50km Ap (while still climbing) burn 0deg pitch until Ap of 70-80km and turn off the engines
9. around 40-20s before Ap, burn to circularize orbit

... suddenly replies, replies everywhere (I'm such a slow poster >_<)

Burn max until you reach about 200m/s. (this is the optimal tradeoff between gravity drag and air resistance)
Then throttle down to about 20%.
Then slowly throttle up while gravity turning towards 90 degrees(in case you want to transfer to a planet further out than Kerbal, if you want to go closer to the sun, pick 270 degrees.

Gravity turning means using gravity to turn the craft from straight up to the horizon.
Then burn prograde until you have an orbit, as you already know.

Try using Mechjeb's ascent autopilot and you'll see that he keeps speed under 100m/s at lower altitudes due to drag i think just for vertical ascent it uses the most efficient way possible.
As LoSboccacc also pointed out you can go to any planet from almost any orbit, when launching 270deg you are burning more fuel to get to orbit since Kerth is rotating.
Also gravity turning does not "use" gravity to turn >_< idk who thought that term was good as it confuses most people. You just use kinetic energy of going upwards to give time to accelerate forward at low drag altitudes, its all simple vector math.

[ank]

Also gravity turning does not "use" gravity to turn >_< idk who thought that term was good as it confuses most people. You just use kinetic energy of going upwards to give time to accelerate forward at low drag altitudes, its all simple vector math.

Gravity turning is simply letting your rocket fall slowly over to one side, like if it was stationary and you pushed the top enough to make it topple over.
Simple as that, the only advantage is not burning fuel to adjust heading.(which is not accounted for in KSP).

Gravity turning is not more efficient in KSP but it gives bonus realism points.

Considering max speed in lower atmosphere, we have found with tests to be about 200m/s.
Just because MechJeb goes to 100 m/s does not mean that is most efficient.(I consider mechjeb cheating anyways)

I'd recommend doing 2 test with the same rocket, one going at 100 m/s and one going 200 m/s in the lower atmosphere.

[Rose]

Personally, I just fly up to 60km or so, then turn to the horizon, and burn till orbit, but that's because I can't steer at all till the first stage falls away, due to lag.