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New to KSP & Trying to leave the atmosphere


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I've made it up to 35km or so with a massive solid rocket booster and FL-T400s as my second stage. The massive solid booster is gone from my inventory now and I don't really know why, it was called rockomax or something to that effect .. Anyway, I haven't yet completed the mission of leaving the atmosphere, I can't seem to keep many of my launches going up completely straight. The 35km launch seems to be a fluke. My rockets are symetical so it's not weighed down on one side. If anyone has any beginners advice for me, that'd be greatly appreciated

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yep, to reach space DON"T go strait up...well sort of,

go strait up until about 10,00m, then turn to 45 on the nav ball, atmo ends at 70k, so burn until AP is higher than that. congrats, Your in space, to stay there, make a maneuver at AP pull the green circle (without the lines crossing it) until the AP and PE are even, if you look at the burn time down to the right of the nav ball, divide that by half and start burning then... until the maneuver is complete... takes some practice but youll be doing it in your sleep soon enough

best wishes... fly safe...

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yep, to reach space DON"T go strait up...well sort of,

go strait up until about 10,00m, then turn to 45 on the nav ball, atmo ends at 70k, so burn until AP is higher than that. congrats, Your in space, to stay there, make a maneuver at AP pull the green circle (without the lines crossing it) until the AP and PE are even, if you look at the burn time down to the right of the nav ball, divide that by half and start burning then... until the maneuver is complete... takes some practice but youll be doing it in your sleep soon enough

best wishes... fly safe...

That's getting orbit, just do straight up for leaving atmosphere..

Sounds like you might not have enough funds (hence the missing solid fuel booster) and that you don't have enough for a control system... Use fins if you have them. You will get more control over the rocket as it gets lighter (reaction wheels in cockpit). If it really comes down to it, just spam cockpits on the sides of your rockets until something better comes along in the tech tree.

If you need funds, do some of those test X landed at Kerbin.

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That's getting orbit, just do straight up for leaving atmosphere..

Sounds like you might not have enough funds (hence the missing solid fuel booster) and that you don't have enough for a control system... Use fins if you have them. You will get more control over the rocket as it gets lighter (reaction wheels in cockpit). If it really comes down to it, just spam cockpits on the sides of your rockets until something better comes along in the tech tree.

If you need funds, do some of those test X landed at Kerbin.

thank you you saved me a bit. i need to realy work on how i explain things

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^above is to get into an orbit.. If you just want to "touch space" and not stay there flying straight up is the way to go.

But did you press "T"? Anyway what I often do for small missions such as this, is have 1 large liquid fuel tank followed by the LV T30, and at the sides put 6 (or less/more) boosters the boosters I throw away after they are burned through. I put on all engines, however I lower the thrust of the middle liquid rocket.

When sas (activated by "T") has difficulty keeping the aircraft straight (the point starts moving away more than the yellow circle) I increase the thrust of my liquid engine, until I go straight/whatever I wish again.

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If you're in career, maybe you got the booster as a one-off from a testing contract?

Turn SAS on, with T, to help keep your rocket on course. If it still veers add more control. Reaction wheels can go anywhere but fins should go at the bottom.

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Ah! The first great hurdle of exploring the universe...and a great one at that! Welcome to KSP, my friend! :D

I can remember myself trying to get out of the atmosphere in my early KSP days. But you're looking for help, so enough of the backstory stuff. You're going to need a powerful rocket. There is a magical number to each rocket called "delta-v," or, in professional terms, ÃŽâ€v. Delta means "change," and v stands for "velocity." ÃŽâ€v is how much your rocket can change its velocity, whether it be done to increase or decrease speed, change inclination, or maybe something else. For low Kerbin orbit, you'll need at least approximately 4500 meters a second of ÃŽâ€v. Orbital velocity, or the speed you must acquire to orbit a celestial body, at low Kerbin orbit is a bit over 2 kilometers a second. Big your rocket big. I like to have a large, powerful 25x4 Kerbodyne engine in the middle of a launch stangem with its tanks surrounded by eight of the biggest solid rocket boosters. Works like a charm, and can carry almost anything into orbit!

So, you may have a rocket capable of achieving orbit, but how exactly do you get it into orbit? There are many ways, but they all comprise of one thing: a gravity turn. If you've ever seen a real-life rocket launch (which you probably have, whether it be in person or on a video), you'll notice the spacecraft turns over sideways as it climbs. What's happening there is that the rocket it trying to get as much horizontal velocity as possible, while maintaining a vertical climb, as well. Vertical velocity is easy to obtain, but horizontal velocity..well...not so much. But you need enough horizontal velocity to keep gravity from pulling you down. So, when do you start this gravity turn? Really, everyone starts at different points. I myself like to wait until my rocket is travelling over 300 meters a second, then I pull the nose down towards the horizon, gradually. Don't do it too fast, don't do it too slow, and you're golden!

There are in-game tutorials to help, and really, they are super helpful. There's also many good tutorials on YouTube. If you haven't done so, please check out Scott Manley for his outstanding tutorials. He taught me so much I know today.

But anyways, I hope this helps! I always love meeting new members of the KSP community, and I'm always willing to help them out! :D

Edited by Thomas988
Gotta cite my sources!
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In Career Mode, you can easily do a suborbital with this simple two stage SRB. Just tilt slightly towards the East using the D key so that it will land in the water. Tweak the first stage to 75% thrust and the second to 40% thrust. It is capable of reaching over 100,000 meters with two Goo canisters.

J414vKk.jpg

This design, as you should have collected enough Science to unlock the bigger SRBs and radical decouplers, will go into a 100k orbit with plenty of fuel left in the third stage for high orbit or even a Mun flyby. You will need to learn how to do an orbital turn for success. Second stage engine is a LV-30. Third stage the LV-909.

FhIv6fn.jpg

Fly this going straight up until the SRBs, tweaked to 60% thrust, are staged. Start gradually turning East getting to about 45* around 25,000 meters. Go into Map mode and fly using the Navball. Keep turning following the pro-grade marker until apogee reaches orbit, I prefer 100k. Cut power. Either add a Maneuver mode and set it until orbit, or aim the ship to the horizon. Restart the engine when the ship is about 15 seconds from apogee. You will have to switch to outside view and stage the rocket before it gets into orbit when the fuel runs out. Go back to map mode and continue the burn until you see your in orbit with the pro and retrograde marker about 100k or more, then shut down.

To return, burn retrograde until the paragree drops into the ground.

Edited by SRV Ron
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First off: do the tutorials. They help, they really do. KSP is not a first person shooter: it is literally simulated rocket science.

Second, getting to space is easy: just go up. Getting to orbit is much harder: in KSP, you spend about equal effort going sideways as you spend going up, whereas in the real world, you spend far, far more effort going sideways than upwards.

Third, there are two main characteristics of a rocket stage: delta-V, capacity to change velocity, and thrust-to-weight ratio, which is how much your rockets push divided by their weight. As mentioned, in stock KSP, you need about 4400-4500 m/s of delta-V to reach orbit. Delta-V comes out of the Tsiolkovsky rocket equation: delta-V = G * Isp * ln(full mass / dry mass). G is Kerbin surface gravity, 9.82 m/s^2, Isp is specific impulse, how efficient the engine is, ln is the natural log function (this is an evil demon who feeds on the tears of KSP players), and the full mass / dry mass essentially means that, the greater the ratio of fuel to other stuff, the farther you go.

The G * Isp term comes out to equal how fast the exhaust gases are traveling: engines which propel their exhaust out faster get more delta-V out of each kilogram of propellant. The reason we use G * Isp instead of just exhaust velocity is that scientists in different countries got frustrated by constantly converting specific impulse between meters/second and feet/second, divided by Earth's surface gravity, and got a measure independent of which set of units you were using. The natural log function is one which steeply decays: when the ratio of full/empty mass is close to 1, you get almost linear delta-V increase (going from 5 kg of propellant to 10 would almost double delta-V), but when you start getting big ratios, you see decreasing gains from adding more fuel. More on this later.

Thrust-to-weight is crucial during ascent: you need to get to orbital velocity as fast as you can, because the longer you spend screwing around at suborbital velocities, the more delta-V you lose fighting gravity. However, you also have to account for two things: atmospheric drag and engine mass. Atmospheric drag increases with velocity and decreases with altitude. As it turns out, for the vertical part of your ascent, the ideal speed is terminal velocity, where the force of gravity exactly equals the force of atmospheric drag: have less TWR, and you waste fuel fighting gravity, have more TWR, and you waste fuel fighting atmospheric drag. You also have to account for the mass of the engines: in the rocket equation, the rocket engines are dead mass. As such, it favors having lighter weight engines, even at the cost of TWR.

How it usually shakes out is that you want your launch to be a little bit short of 2.0 TWR, throttle your engines to maintain terminal velocity (which will go up as atmosphere gets thinner), and then have progressively less TWR as you go up stages and have less need for thrust: once you're most of the way to orbit, you can coast on any remaining upwards velocity, and the fact that your suborbital horizontal velocity will reduce the effective amount of gravity that you feel.

The last thing I'm going to say (this is going on rather long) is a bit on staging. You know that ln(full / empty mass) term? There is a theoretical limit, which is determined by the mass of a full fuel tank divided by its empty mass: in stock KSP, that ratio is 9:1 for the most efficient fuel tanks (KSP fuel tanks are much heavier than real-world counterparts). The solution to this is staging: dumping off empty fuel tanks and thus resetting the rocket equation. This usually means dumping off engines as well: this is a blessing and a curse. It is a blessing because engines are dead weight, and you do not need as much engine mass for your next, lighter-weight stage, and it is a curse because now you've got to add new rockets for your next stage. There are funny schemes like asparagus staging and onion staging which play with this a bit, but for now, simple staging should suffice for your first rocket. There are vertical decouplers like the TR-18A which dump off stuff below, and radial decouplers like the TT-38K which let you dump off engines attached to the side of that part. Both are useful.

Finally, throw out the advice I gave you regarding launch TWR if you ever install FAR or NEAR, two mods which make aerodynamic drag much more realistic. In stock KSP, drag is proportional to the mass of a part, which is a stupid approximation which lets you get away with stupid launch profiles: its sole advantages are A: it's simple and forgiving for new players, and B: it exists.

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Too many complicated suggestions on here. Just go on YouTube and look up "Scott Manley", his videos will teach you all the basics you need to know including ship design.
I dunno. While sure, they'll do that, I think it's better for new players to reach the key early milestones without being told what to do by a tutorial. Get to space, get to orbit, flyby or impact the Mun. These are all things one can figure out by experimentation without it taking too long. Most of the game's challenge comes from working out what to do so tutorials take away a lot of that.
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I dunno. While sure, they'll do that, I think it's better for new players to reach the key early milestones without being told what to do by a tutorial. Get to space, get to orbit, flyby or impact the Mun. These are all things one can figure out by experimentation without it taking too long. Most of the game's challenge comes from working out what to do so tutorials take away a lot of that.

Indeed. The Kerbal Rocket Science School of Hard Knocks. Build something and test it. If it doesn't work, try something else. If it does, improve on the design and learn how to fly it better. One learns a lot more on what works rather then depending on the aid of Mech Jeb and other flight mods. You can use those mods later for assembling space stations or deep space missions in orbit when you know how to fly manually.

Finally, build simple. It is a lot easier to learn how to fly then building huge designs prone to going out of control or blowing up soon after launch.

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the big Solid Rocket boster is something with BACC i think... if you are playing career mode you might have had a contract to test it on the runway/launchpad and that would be why its disappeared.

as for getting into orbit. other people can explain a lot better than i can.

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Two threads, two posts, same subject, same answers (with some more suggestions).

  • Play the tutorials in-game.
  • Watch some 'getting to orbit' tutorial videos.
  • READ some details if it's still not clear.
  • ALL you need - a Stayputnik probe-core, an FL-T100 fuel tank, a 48-7S engine. 'Launch' from the VAB, press 'T' to engage SAS, press 'Space' to go there.
  • If any of that is unclear; welcome to the world of orbital mechanics and spacecraft design. It IS rocket science!

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My two cents to that subject,

Try for your self how to get it done, tutorials for different rocketdesigns are helpfull but don't watch a guide that takes you to the orbit, you will fall in the habit to only watch guides and stop trying by your self. Get into KSP, be frustrated but be happy when you get it done!

I would recommend starting off with a sandbox to learn a bit and build rockets without cashlimit.

Thing i wanna give you for your way, don't kil jeb :) take parachutes with you and try to use liquid engines as mainengines and mount the boosters around it, boosters should always be a help to lift, not your 100% mainengine (my opinion). If you don't have (in career) radial separators, then you did it right, but maybee was missing the liquid engine for the last bits ;)

As most ppl said, to space -> straight up, to orbit -> Gravity turn at 10km-15km.

That's all you should need to know for now, explore and get it done ;)

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