I Can't Escape Kerbin ;c

[Zenechules]

I can make it to the edge of space or a little into space then my orbit throws me back into Kerbin, so I guess my question is how do I change orbit? I set the Mun as the focus a few times but that doesn't seem to help much. I think my highest was (120,000 m) but I run out of fuel then get forced back. I also see the "change maneuver" option but it hasn't worked for me thus far.

:confused:Note: This is my first day on the KSP forums & KSP itself, and I have not watched the tutorials as I learn better doing then watching, I have been learning progressively, the main thing I learned on day one was weight distribution importance, I wasted much time on ships that never even left the launch pad because of the initial pitch or rocket/missle displacements.

[Red Iron Crown]

This is more of a gameplay question, moving to the Gameplay Questions forum.

[Zuqq]

As awesome as it is to learn by doing, sometimes it's a lot easier and quicker to watch some videos. Especially with a game as complicated as this.

I learned to play by watching

by Scott Manley (it is a little dated now with 0.9 out, but it does a great job covering the basics) on one screen, and following along in-game on my other screen. It was extremely helpful.

It would help to know how you are designing your craft, do you follow any sort of ascent profile or just shoot up, etc.

[Nitrous Oxide]

So what you want to do is move in a circle, not straight up. Orbital mechanics are all about motion in elliptical patterns... 120km is more than enough as you can achieve stable orbit with only 70km... sounds like you're not focusing on the other half of your orbit though. Remember the concept is falling fast enough that you don't come back to the ground.

So instead of burning directly up, you should be angling yourself 45 degrees after 10km (assuming you play stock) and gradually evening out so that once you reach space, you're burning parallel to the ground in the direction of your orbit.

Edited January 19, 2015 by Nitrous Oxide

[tater]

Have you tried the tutorials in game?

[Alshain]

Just remember this rule of thumb.

"Vertical velocity is eaten by gravity, but horizontal velocity is yours to keep forever."

If you are burning straight up, you will never reach orbit. Based on your explanation above I'd say that is what you are doing. Once you leave the atmosphere you need to circularize by burning horizontal to the planet in the direction you are traveling, the term for this is "prograde". You said you made it to 120k, atmosphere ends at 70k, so you are getting well beyond where you need to be. Turn to the prograde marker and burn when you get close to the highest point in your arch, called the Apoapsis, which is visible in map mode.

For stock aero most people do this:

1. Burn straight up till you hit 10km

2. Turn to 90 degrees at a 45 degree angle.

3. Burn till you apoapsis is 70k+ (a little further may be desired because you are a beginner 80k would be good).

4. Cut engines and wait till you approach apoapsis

5. Burn toward the prograde marker till your periapsis (lowest point in the arch/orbit) is above atmosphere (again 70k).

Later you will learn to do this in precision with maneuver nodes but it's not required. When you do get it done with maneuver nodes for the most accurate burn you want to split the burn time and start burning half the time before reaching the node. So if you burn time is 1 minute, start burning 30 seconds before you reach Apoapsis.

Be warned: This game is in beta and it just so happens aerodynamics are changing in the next patch so this procedure will change too. (A more real gravity turn doesn't sharply turn to 45 degrees at 10k, it turns more gradually and eventually burns almost completely on the artificial horizon)

Edited January 19, 2015 by Alshain

[Zenechules]

Okay Red, thanks I didn't see that sub-forum,

Thank you too Zuqq for the link, I am learning a lot from this playlist; I have been playing sandbox as well. Normally I try to keep it small or medium sized as I've had no success with large ships, I normally use something like this(other side) as I've had most success with generic designs; something powerful at first to let go and smaller engines to keep you going, I'm sure there's better engines / fuel tanks to use as well.

- - - Updated - - -

Okay, thanks as well Alshain & Nitrous Oxide.

If you are burning straight up, you will never reach orbit. Based on your explanation above I'd say that is what you are doing. Once you leave the atmosphere you need to circularize by burning horizontal to the planet in the direction you are traveling, the term for this is "prograde". You said you made it to 120k, atmosphere ends at 70k, so you are getting well beyond where you need to be. Turn to the prograde marker and burn when you get close to the highest point in your arch, called the Apoapsis, which is visible in map mode.

Yes I have been flying nearly straight up or at a slight slant, never 45 degrees, also at high altitudes when I decouple the initial rocket & tanks, even the slightest turn seems to start spinning the ship uncontrollably, hence why I continued to try and go vertical. I am going to try heading up at 45 degrees as everyone has said must be done here. I also look forward to what the dev. team has in store for aerodynamics.

Oh this may be worth mentioning too, should I add any aerodynamic "wings" vertically to my craft? or should you avoid them on shuttles?

Edited January 19, 2015 by Zenechules

[RainDreamer]

Obligated "MOAR BOOSTER!!!1!" comment here.

[Zuqq]

Make sure you enable SAS (press 't'), and that your COM isn't offset. Adding stabilizers to a rocket is generally a good idea if you are having trouble controlling (or maintaining stability, executing your gravity turn etc) your rocket in atmosphere.

[Nitrous Oxide]

Yes I have been flying nearly straight up or at a slight slant, never 45 degrees, also at high altitudes when I decouple the initial rocket & tanks, even the slightest turn seems to start spinning the ship uncontrollably, hence why I continued to try and go vertical. I am going to try heading up at 45 degrees as everyone has said must be done here. I also look forward to what the dev. team has in store for aerodynamics.

Oh this may be worth mentioning too, should I add any aerodynamic "wings" vertically to my craft? or should you avoid them on shuttles?

Wings don't really work quite as intended in stock, though I've used fins on my rockets to stabilize them in the atmosphere... it's just a bit unorthodox compared to how rockets are actually supposed to handle... the key is really SAS (Stability Augmentation System) aka reaction wheels. Place it near the center of mass or equally offset if you have more than one (the capsule usually has one). Otherwise you have to fly manually, tapping the keyboard furiously trying to hold your rocket against the soup.

[Zenechules]

Make sure you enable SAS (press 't'), and that your COM isn't offset. Adding stabilizers to a rocket is generally a good idea if you are having trouble controlling (or maintaining stability, executing your gravity turn etc) your rocket in atmosphere.

Okay, I will add a few stabilizers to keep it smooth and I had no idea I had to enable SAS, when should you enable that? when entering apoapsis?

Otherwise you have to fly manually, tapping the keyboard furiously trying to hold your rocket against the soup.

Yeah that is what I've been having to do going up, and it gets kind of hectic after you throw off that initial weight. But there's an idea that they could add collapsible wings that can be opened when needed and closed when not, like the solar panels

[Zuqq]

Turn your SAS on right on the launch pad, and you should have a much safer (and easier) ride!

[Zenechules]

Okay will do, thanks Zuqq and everybody for your help, I've finally made orbit!

Now to send more up and connect them:)

Edited January 19, 2015 by Zenechules

[KSK]

Okay will do, thanks Zuqq and everybody for your help, I've finally made orbit!

Now to send more up and connect them:)

Grats! You always remember your first orbit.

Without wishing to tell you how to play though, you can make it to orbit with much simpler rockets that you might find easier to fly whilst you're getting the hang of things. Happy to post a couple of suggestions here if you like, but I don't want to spoiler you!

[moogoob]

Congrats! You might want to try a simple 2-stage design next - bigger engine with lots of fuel on the bottom to get you up, then ditch that high up when it's out of fuel and use a smaller one to make orbit, hopefully with enough fuel to get your Kerbal back home. Don't forget the 'chute!

[Zenechules]

Grats! You always remember your first orbit.

Without wishing to tell you how to play though, you can make it to orbit with much simpler rockets that you might find easier to fly whilst you're getting the hang of things. Happy to post a couple of suggestions here if you like, but I don't want to spoiler you!

Thanks, shoot me your suggestions I'd love to see some advanced looking space-crafts.

Congrats! You might want to try a simple 2-stage design next - bigger engine with lots of fuel on the bottom to get you up, then ditch that high up when it's out of fuel and use a smaller one to make orbit, hopefully with enough fuel to get your Kerbal back home. Don't forget the 'chute!

Thank you, and yeah I have tried a design with 6 of the large engine tanks and when I decouple them they end up blowing off my bottom engine, so I have to use two or four which work well; also another problem I have with too big of engines and large ships in general (though this may be my fault due to design) is after I reach a bit after 10,000m I have trouble maintaining it at a good angle even with SAS enabled and sometimes can go into a spiraling mess that can take a bit to get out of, but I'm sure I'll get better at balancing in time.

[*Aqua*]

When your rockets start rotating on its own that's usually a sign that it is not balanced. A common reason is that's parts of your rocket start to bend under the forces applied to them. If these parts don't bend the same way you're rocket will most likey going crazy.

To avoid that, use struts. These can connect two parts of your rocket with a pretty rigid (but not indestructable) connection. You don't have to strut everything, just those parts which are bending.

Also don't turn to quickly in the lower atmosphere. It's easy to mess things up like that. If you start turning over at about 10 km and reaching 45° at about 20 km, it should be ok. Other rockets might need other numbers, experiment!

Edited January 19, 2015 by *Aqua*

[Pecan]

Thanks, shoot me your suggestions ...

The tutorial in my signature explains 30-odd designs from a simple rover to interplanetary tugs, landers and space-stations.

[Kryxal]

Speaking of parachutes, they now cause more drag than most other parts, this can make a rocket unstable in-atmosphere. One design I put together had a couple of chutes to land a stage of the ascent rocket, placed where they would provide drag where it would do good.

Of course, then the thing splashed down at a bit under 7 m/s and ate itself except for the chutes...

[Seshins]

ahh, the first orbit. That satisfaction when achieved for the first time. (took me 30-40 attempts to figure it out!) now it seems like second nature.

Wait until your first successful docking my friend, that is SATISFACTION.

[KerikBalm]

so I guess my question is how do I change orbit?

By doing a burn. To raise your perapsis (which is what you want to do if your trajectory intersects kerbin), burn at apoapsis.

Yes I have been flying nearly straight up or at a slight slant, never 45 degrees, also at high altitudes when I decouple the initial rocket & tanks, even the slightest turn seems to start spinning the ship uncontrollably

Burning straight up = bad... but you've been told that already. One thing to note is that with the current implementation of aerodynamics... terminal velocity is quite low, and if you ascend too fast, you waste a lot of fuel fighting air resistance... more on that spinning later...

See this table:

http://wiki.kerbalspaceprogram.com/wiki/Basic_maneuvers#Ascend_to_orbit

after I reach a bit after 10,000m I have trouble maintaining it at a good angle even with SAS enabled and sometimes can go into a spiraling mess that can take a bit to get out of, but I'm sure I'll get better at balancing in time.

I normally use something like this(other side)

Ok, so I think I see a problem... you are using rapier engines, and they have two modes: closed cycle and Air breathing (open cycle).

By default, they will automatically switch from air breathing to rocket mode when they don't have enough air.

They do not produce the same thrust in rocket vs air breathing mode, particularly if some are starved for air but haven't flamed out yet.

Due to the way intake air works in KSP, unless you place each engine and intake in a specific order, intake air is not distributed evenly among the engines - thus some will have thrust decrease earlier than others, and then flame out and switch to rocket mode before the others. This can cause a severe thrust imbalance, which is likely the cause of your tumbling at 10k (when the air starts to get too thin for them to work in air breathing mode with your ascent profile and intake number).

I suspect you would notice much better results if you just dropped the air intakes, and even better if you switched to LV-T45s or LV-T30s, or even aerospikes or LV-909s.

If you want to make use of the rapier's air breathing, you should be using them in air breathing mode right from the start (have them activate at the same time as the mainsail), they are ridiculously efficient in air breathing mode. Right click and toggle them from automatic switching to manual switching, and then set up an action group to switch them all at once.

To avoid uneven air distribution, place 1 tank without symetry, add an engine and intake, take it off, set the symetry to 4, stick it back on. If you add 4 engines at once, and then 4 intakes at once, 1 engine will get the air from the 4 intakes -> it takes what it needs from what they supply -> the 2nd engine gets the leftovers, and takes what it needs -> the 3rd engine... and so on, obviously this means that engine #4 may be left with nothing as the air gets thin, while engine #1 has a full supply.

A few other comments: You have no parachutes!, that craft has no way of coming down safely.

I can't tell if that is a nosecone, or an atmosphere sensor on the top -> in the current implementation of aerodynamics, nose cones are just dead weight, try sticking a parachute on top instead.

The problems with decoupling the lower stage is that the decoupler has so little clearance, try using the TT-70 radial decoupler instead:

http://wiki.kerbalspaceprogram.com/wiki/TT-70_Radial_Decoupler

Next... that fuel tank under your pod... is dead weight... it has no engine underneath it (a poodle might be more weight than its worth for such a small tank... try radial mount 24-77s ?

Or you can run fuel lines from it to your outer engines... but then there is no point in decoupling the outer engines

[xnorb]

Start out small - and i mean real small.

Adding fuel and especially engines will only benefit you rather little.

Lowering the weight of your rocket makes it so much easier taking your first steps.

You might want to watch some "KSP stock challenge" videos.

There you see how people take only 7 parts to get to places you don't think are possible with 40

[KSK]

Thanks, shoot me your suggestions I'd love to see some advanced looking space-crafts.

Thank you, and yeah I have tried a design with 6 of the large engine tanks and when I decouple them they end up blowing off my bottom engine, so I have to use two or four which work well; also another problem I have with too big of engines and large ships in general (though this may be my fault due to design) is after I reach a bit after 10,000m I have trouble maintaining it at a good angle even with SAS enabled and sometimes can go into a spiraling mess that can take a bit to get out of, but I'm sure I'll get better at balancing in time.

Cool. Pictures to follow tonight, but this is pretty easy to describe. I wouldn't really call it advanced either - more like 'bare minimum to orbit', but it does work and it's quite a nice demonstration that you don't always need a monster rocket. The design breaks down into four sections, each linked by a Rockomax brand decoupler.

Section 1: Crew compartment. Take a Mk1-2 capsule (the same one that you're using in your design). Put a Mk16-XL parachute on top. Done!

Section 2: Service module. Start with a Rockomax X200-8 fuel tank (shortest tank having the same diameter as the base of your capsule). Connect it to your capsule with a decoupler. Put an LV909 engine on the bottom. Add a solar panel to each side - I used the SP-L 1-6 but more on this later.

Section 3: 2nd stage. Connect a Rockomax X200-16 fuel tank to the bottom of your Service Module with another decoupler. Stick a Rockomax Poodle engine on the bottom.

Section 4: 1st stage. Using (you guessed it!) another decoupler, attach a Rockomax X200-32 tank to the bottom of your second stage. Stick another X32 tank under it, and a Rockomax Mainsail engine under that. This is basically the same as the first stage of your design. Stick four AV-R8 steerable winglets around the bottom of the rocket. Add launch clamps to taste.

Design notes

This is a very basic orbital craft. It will put three kerbals into low Kerbin orbit, with enough fuel leftfor some orbital maneuvers, including that all important de-orbit burn to get your Kerbals home. Warranty void if you attempt to take the craft out of Kerbin orbit.

The design is basically a long tube. It keeps everything in-line and almost entirely symmetrical. As you've already found, this keeps the craft balanced and makes it a whole lot easier to fly. The fuel budget is fairly tight, so it may need some practice to get to orbit, but it will get there. I'll have a think about a more forgiving design.

Engine choice. The Mainsail has bags of thrust but isn't terribly efficient. That makes it a decent choice for a main engine, since you need plenty of thrust to get the fully fueled rocket off the launch pad. In contrast, the Poodle is efficient but has relatively poor thrust. It's a good second stage engine for both reasons - the second stage engine is pushing a much lighter rocket so doesn't need enormous amounts of thrust, and a high efficiency second stage minimises the amount of fuel that the first stage needs to lift. Finally, the LV909 is a deliberately small engine since it's only going to be used to finish your climb to orbit, and for orbital maneuvering. Again, high efficiency good, high thrust not required.

Note: The Poodle is not generally regarded as the best choice stats-wise, but it makes for a much simpler design (as it's sized to fit with the other Rockomax parts), and I personally find that it gives a nice flight profile.

Possible modifications.

If you want a more general workhorse craft for orbital operations, you could try the following steps: 1. Strip out the decoupler between your capsule and Service Module. This is primarily included for aesthetics, so that you can deorbit your crew behind a heat shield. However, unless you're using realism mods, there is no atmospheric heating to take into account, so deorbiting the capsule and service module together is fine.

2. Swap out the relatively heavy solar panels for lighter ones. 3. Replace the XL parachute with a docking port, 4. Add a pair of radially mounted parachutes to the capsule. 5. You could also try stripping off the winglets for another small weight saving. The Mainsail gimbals should be enough for steering.

Pilot checklist

Important - this design does not include an SAS module, so a pilot will be required.

Press T to engage SAS.

Press Z to throttle up to max.

Check your staging sequence (bottom left of screen). All set? Good - KSC, we are Go for launch!

Press Space...

Fly straight up to 9-10,000 metres.

Pitch over 45 degrees, heading due East, or as close as you can manage. Your first stage should flame out shortly afterwards. You should be flying at around 800 m/s.

Drop the first stage and fire up the Poodle. The rest of the flight to orbit is much easier to do from the Map screen.

Slowly pitch over to 90 degrees, keeping an eye on your apoapsis. As a rule of thumb, I tend to keep at 45 degrees until my apoapsis hits 30 km, then start the final pitch over. By the time my apoapsis is at 60-65 km, my capsule nose will be pointing along the horizon.

Wait till your apoapsis hits 100km (roughly - anything above 70km is fine!) and shut down your engines.

Coast up to apoapsis. Restart your engines just before you get there and keep burning until your periapsis gets above 70 km. Your second stage will run out of fuel mid-burn, so just drop it and finish with your service module engine.

Edited January 20, 2015 by KSK

[Pecan]

...'bare minimum to orbit'

...don't always need a monster rocket.

...four sections,

...This is a very basic orbital craft...

You do very complicated "bare minimum", don't you?!

Mk1-2 pod, jumbo 64 (orange tube) and X200-8 fuel tanks, skipper engine = enough to SSTO, de-orbit and perform a powered landing.

Not exactly easy to fly though so add an advanced reaction wheel, large, between the pod and orange tube.

For reliability and easier landing add a Mk25 drogue parachute to the top of the pod, two radial parachutes, two OX-STAT solar panels and one Z-100 battery to its sides.

Set staging as 0: radial parachutes, 1: drogue parachute, 2: engine.

48.32t, 11 parts, cost 25,230. Kerbin TWR 1.37, 4,965m/s vacuum deltaV.

Edited January 20, 2015 by Pecan

[KSK]

It didn't seem that complicated but maybe I've been playing too long!

I will say that mine is quite forgiving to actually pilot, even if you need to pilot it reasonably well to get to orbit. The lowish thrust on the Poodle means that the second stage burn is quite long which gives you time to react if you're still getting used to orbiting stuff. Plus mine gives you a dinky little spaceship to fly about once you get to orbit, rather than a hulking great Jumbo-64.

Either way, that's two, low part count ships for the OP to try out!

Edit - pic.

Edited January 20, 2015 by KSK