Cant orbit kerbin anymore

[Rayge]

Ok Guys, I recently made a thread about how i got stuck orbiting the sun. now my problem is, i cant orbit kerbin, I always overshoot and orbit the sun and no longer how hard i fight i dont have the skill to fix my orbit, Any assistance? if its possible? I didnt even know anyone could make this mistake.

Edit: I can return to kerbin now from the help on my other thread, but i just want to orbit kerbin..

Edited November 18, 2014 by Rayge

[Belphegor]

well that's weird. do you have the sun set as the target maybe? kerbin orbits around the sun so when you orbit kerbin you technically also orbit around the sun.. is it just the stats that are off (altitude, speed etc.) or is your craft not being influenced by kerbin's gravity?

[Rayge]

no, i checked the target thing, and the gravity affects me quite a bit. i think, i just do my turning wrong to make an orbit. like at 10,000m I do the first turn, then I hold it till around 70,000m, Then turn completely to the side, next thing i know my orbit grows into a line. if needed i can probably make a quick vid showing it.

[Abdu]

i think you have "hack gravity" on Press alt+F12 and check if its on, if its not on maybe you got some mods installed ?

[Rayge]

couple mods. the only modded parts on my ship are kw stuff. and i dont have hack gravity, though i did use inf. gas at one point. could that be it?

[Belphegor]

strange. have you tried with an different craft? maybe the one you're currently using summons the Kraken somehow.. and what altitude are you at when the orbit changes into a line?

yeah a vid or some pics would be nice

[Rayge]

same thing happens with multiple crafts, and whats the kraken..? and ill check all then soon, im on my phone right now, away from my house

[Belphegor]

the Kraken is this annoying little bug that likes to poke a glowing hot metal bar into the butt-cheeks of physics. it sends vessels flying off at the speed of light, usually in tiny pieces. but it doesn't happen often. some people have managed to reproduce it with clever craft designs, that was why i was thinking it might have been your spacecraft..

like at 10,000m I do the first turn, then I hold it till around 70,000m, Then turn completely to the side

this may be a stupid question, forgive me for asking. do you keep the thrusters activated until you reach 70km? because this will raise your apothingy way way higher than 70km and possibly out of kerbins SOI

[Wanderfound]

It does sound like a piloting issue. In a craft with a decent amount of thrust, it's quite easy to hit escape velocity while still in Kerbin's atmosphere:

During ascent, shut down engines as soon as your apoapsis reaches the altitude of your desired orbit. Then, coast until just before apoapsis, point just below prograde and do your circularisation burn. You don't burn all the way up unless you're doing an extremely shallow ascent:

Even then, you'll still usually shut down and coast for a bit before apoapsis.

[Red Iron Crown]

Very simply, to attain orbit first go up fast, then go sideways very fast.

More specifically, climb straight up until 10km or so, then gradually turn east. Switch to map view (and open the navball), and watch your apoapsis get higher and higher. Once it hits 80km or so, cut your engines and coast to the top of your trajectory, then point due east (90 degrees, pointing where the brown meets blue on the navball) and start burning again. Watch the orbit start to spread, eventually the periapsis marker will appear. Once the periapsis reaches 70km or more, cut your engines and enjoy your orbit.

You might want to check out some of the tutorials listed on The Drawing Board to help you figure out what's going on more specifically.

[Scarecrow88]

.... like at 10,000m I do the first turn, then I hold it till around 70,000m, Then turn completely to the side, next thing i know my orbit grows into a line.

From that line in your post, it sounds to me that when you do your burn at 70k, you're either burning in the wrong direction or you are burning too long, so that your velocity gets to the point where it is enough to escape Kerbin's influence and putting you in to a solar orbit.

[eddiew]

no, i checked the target thing, and the gravity affects me quite a bit. i think, i just do my turning wrong to make an orbit. like at 10,000m I do the first turn, then I hold it till around 70,000m, Then turn completely to the side, next thing i know my orbit grows into a line. if needed i can probably make a quick vid showing it.

The way you describe it sounds like a massive over-thrust, perhaps constantly burning your engines all the way to the top of the atmosphere? This will easily shoot you way, way too far. A couple of thousand delta-v once you're above the thick atmosphere (30-35km) could well lead to an escape trajectory - i.e. a line out of Kerbin's SOI.

I'll ask the obvious and query whether you're...

a) watching your apoapsis on the way up to see where you'll be peaking out?

shutting off your engines when it's high enough? (If the apoapsis is reading 75km or up, and you're at 35km+ and 1200m/s or over, you can generally cut thrust and just coast the rest of the way.*)

c) setting a navball manoeuvre node at apoapsis to give you a marker for which direction to burn when you reach it? (Just drag the prograde marker until you see a projected stable orbit.)

d) timing that burn correctly, e.g. if it says "est 30 seconds" do you start at 15s before the node, so's to balance it out? (Burning at T-30s for a 30s burn will raise your apoapsis.)

Sorry if these questions are overly basic, but seems worth checking

* Numbers pulled from personal experience, using Ferram Aerodynamics Research. Speeds and altitudes may vary for stock!

Edited November 18, 2014 by eddiew
poor grammar, clarity on manoeuvre timing

[goldenpsp]

no, i checked the target thing, and the gravity affects me quite a bit. i think, i just do my turning wrong to make an orbit. like at 10,000m I do the first turn, then I hold it till around 70,000m, Then turn completely to the side, next thing i know my orbit grows into a line. if needed i can probably make a quick vid showing it.

Yes like others have said, sounds like you are just burning too much. Generally by the time you reach 70km you should have an AP more than high enough if not too high, at which point you should turn off your engines and coast to AP and then do a circularizing burn.

[CmdrBone]

You said you "hold it til 70.000 metres" - you mean you accelerate until 70.000? Because that would explain your problems.

The map view is the best tool for achieving orbit, always watch the Periapsis marker, like Red Iron Crown mentioned.

[Taki117]

if needed i can probably make a quick vid showing it.

This would certainly help us since It sounds like piloting error and or too much thrust.

[ratchet freak]

during your ascent go to the map view and see how your orbit evolves, pay special attention to the apoapsis and where it is

[Aethon]

The video would help us to help you. From what you've said, I'll say this :

On the way to 10,000m control your speed. If you go too fast, you waste fuel pushing against the atmosphere. At 1000 m A(bove) S(ea) L(evel) go no faster than 110m/s, at 2000m ASL the limit is 120 m/s, 3000m ASL= 130m/s, 4000m ASL= 150m/s, 5000m ASL= 160m/s, 10,000 m ASL= 260m/s. After that you'll have trouble hitting terminal velocity in the stock souposphere.

At 10,000m start your turn to 90 deg. on the navball. Switch to map view, bring up the navball, and keep your cursor over the projected apoapsis. Continue your turn using throttle control to keep your time to apoapsis between 40 and 50 seconds. When your AP(oapsis) reaches 100km kill your engine.

Coast phase. When the music starts, you are above the atmosphere. Now you can set up a maneuver node exactly on your apoapsis ( make sure time to AP and time to maneuver are the same ), which will burn you prograde, and circularize your orbit around 100km. Execute the burn and enjoy.

Hope this helps.

Edit- Follow the Manley.

Edited November 19, 2014 by Aethon

[Rayge]

Thanks everyone for the help!! The problem I have seems to be i over-thrust. Thanks so much! I can finally make an orbit again.

[eddiew]

Thanks everyone for the help!! The problem I have seems to be i over-thrust. Thanks so much! I can finally make an orbit again.

Good stuff, glad you're sorted buddy, enjoy the space race

[Rayge]

Good stuff, glad you're sorted buddy, enjoy the space race

Thanks!!!!!

[LordFerret]

Very simply, to attain orbit first go up fast, then go sideways very fast. ...

That made me laugh. Thank you. I needed it.

[DrD]

Another concept that I find very interesting is this:

If you burn just sideways to attain orbit, how is it that your altitude increases?

The answer is simply that the planet curves beneath you, such that if you're going say completely straight sideways with respect to space then your distance to the ground will go up.

In fact that's the very concept of an orbit, as you fall your forward velocity is such that the planet curves aways from you faster than you fall so you never hit the ground.

[LordFerret]

Another concept that I find very interesting is this:

If you burn just sideways to attain orbit, how is it that your altitude increases?

The answer is simply that the planet curves beneath you, such that if you're going say completely straight sideways with respect to space then your distance to the ground will go up.

In fact that's the very concept of an orbit, as you fall your forward velocity is such that the planet curves aways from you faster than you fall so you never hit the ground.

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