Orbits For Dummies

[*Asterix*]

I've recently visited the Kerbal Space Program forums, and I realized after playing since v0.18.0, I should start making contributions to the forums. So here I am. And I have a quick thing to say to beginners.

ORBITING IS HARD

I see a lot of new players in Kerbal Space Program struggling to get into orbit, and I mean, for new players, it's understandable.

Now I'm sure there is thousands of tutorials out there for this, but I figure the more the merrier when it comes to this, to be honest. So, this is my first ever forums tutorial. New players, grab your snacks, and hold on for the ride.

The Basics

Getting to orbit isn't hard. It's just...okay. It's hard when you're new. I get it. Well, there are some things you should have done before trying to orbit.

- Knowing the terminology

- Knowing the controls by heart

- Flown at least 3 suborbital flights

- Watched Youtube (I'm Serious)

So, if you have accomplished these tasks, then we are ready to begin with the tutorial.

Launch Vehicles

"What is a launch vehicle," some may say. It's the part of your rocket that gets you moving up. AKA your lower stages, or "launch stages". Most launch stages contain at least 1 engine, a couple fuel tanks, and commonly SRBs or winglets. I'm not a fan of winglets, since MechJeb is my friend, but add them if you wish. The lower stages should lift you to a sustainable altitude, and for me that means about 80km, but if testing a lot isn't your thing, shoot for 72-75km. The upper stage, which will be attached directly to the pod, should contain enough Delta V to raise your Periapsis from Kerbin's core, to about the height of your apoapsis. A lot of times with launch vehicles, some stages do more than you expect, like using a lower stage to circularize, or do less, like having to use the upper stage to raise the apoapsis. But now, on with the specifics.

Flight Specifics

How to fly your rocket is a key part to achieve that sweet, sweet orbit. But it requires some manual interaction to achieve a circular orbit. Keep in mind that overstressing this procedure is really not recommended. Just don't do it, please. So when you get ready to launch, follow my LKO (Low Kerbin Orbit: 72-300km) flight procedure.

- Enable SAS

- Throttle to 100%

- Press SPACE (Liftoff)

- Keep the rocket at 10 degrees after launch and slowly ascend, changing the angle very slightly, so you are at 90 degrees as you reach the apoapsis

- Stage as necessary

- As you reach space, create a maneuver node (click on orbit > create node)

- Pull the PROGRADE marker until the apoapsis and periapsis are within 5km of each other, give or take

- Congratulations, your are in orbit, Junior Rocketeer!

Any questions, suggestions, or corrections, just send a reply.

I would love to hear your results using this procedure! I will constantly check the replies!

"I am good at this game, in the Jebediah Kerman sort of way."

Edited October 12, 2015 by *Asterix*
Various feedback from people who know more than me. Heh heh.

[*Asterix*]

Sorry about the length. I'll work on cutting it down.

[Gaarst]

You shouldn't go straight up and turn at 7-12km as you said. Bad habit, and it won't help new players.

[kStrout]

No one has got to orbit that way since the aerodynamic overhaul. What you want to do now for the first four steps is fine, but don't throttle down at 100m/s(if you are worried about efficiency, you will not go too fast to soon if your launch TWR is < 2)(note this is my preference, but the following is proven to be better). And turn over almost immediately, at around 1km you should be at ~10° from upwards, and keep your nose pointed at the prograde marker as it slowly falls towards the horizon, this is called a gravity turn. (you can use the hold prograde button in the SAS menu) You should be at 45° at 10km, just keep the gravity turn until your apoapsis is at your desired orbit height, unless your time to apoapsis(viewable by hovering over the apoapsis marker in map view) starts decreasing, then you should pull your nose up until it stops and keep going.

Not to stomp all over your system, it may be that more experienced players will point out errors in my system, that's just part of learning. I love what you are doing though, it is certainly true that most people on the forums assume new players will already know how to get to orbit, and your format is excellent.

[Scarecrow88]

If you've been relying on MechJeb to get you to orbit, that would explain why the method you outline above is actually outdated, and no longer fits as an efficient means of getting to orbit in the current aerodynamic model. As has already been pointed out by previous posters, you're gravity turn should be started now much earlier than was the case in earlier versions of KSP, in fact almost as soon as you leave the launch pad. I would also recommend using a manoeuvre node at apoapsis, once apo has been established, as it makes it easier to see how much burn is required to circularise the orbit.

[*Asterix*]

Thanks for the feedback. Actually, I've been experimenting with different methods, and I found mine still works pretty well for the most part with my launch vehicles. MechJeb Ascent Guidance actually doesn't perform this way as it constantly tips, starting from 10 degrees at launch all the way to 90 degrees at Apoaps. I'll revise it a bit, and thanks for the corrections.