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amateur astronaut

i need help about my basic rocketry fails

Question

1. drifting: sometimes i just launch a rocket and when i try to make my orbit by turning into a 40 degree its starts to drift (sometimes i turn it at 7000 m, when i want a lower orbit, when i want to visit a planet i turn it at 14000)

2. spinning around the navbal:l sometimes i use struts, but whenever i try, my rocket becomes instabile, and starts to make a delicate spinning around the nawball. this is very annoying because when i try to modify my orbit, its sometimes modify it vertically too.

3.making orbits: my basic  method to do an orbit is to fly up to 14000 m, and then turn it to 40 degree. after that, at 30 000 m i turn my rocket to 90 degree. when my periapsis comes out from kerbin, i travel to the apoapsis to make a burn in prograde, and make my orbit "circular". i think its a very primitive and fuel-wasting method, so somebody pls tell me (or take in a scott manley tutor i dunno) how to do it.

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1 hour ago, amateur astronaut said:

3.making orbits: my basic  method to do an orbit is to fly up to 14000 m, and then turn it to 40 degree. after that, at 30 000 m i turn my rocket to 90 degree. when my periapsis comes out from kerbin, i travel to the apoapsis to make a burn in prograde, and make my orbit "circular". i think its a very primitive and fuel-wasting method, so somebody pls tell me (or take in a scott manley tutor i dunno) how to do it.

Try to fly more of a real gravity turn: go strait up till you're going about 100 meters per second, tilt about 10 degrees downrange, and then just set SAS to prograde (:prograde:) and the rocket will practically fly itself the rest of the way up. Keep an eye on the throttle--adjust it to keep the G-meter somewhere between 1 and 2 Gs--stop the engine when you hit your intended apoapsis, coast, and burn to circularize the same way you always do.

An added benefit to this is that, because the rocket spends most of the flight at zero angle of attack, it's much less likely to flip even if it's not all that aerodynamically stable. Just make sure you have enough control authority--tail fins, gimballing engines, or reaction wheels--and you should be OK as long as your rocket is reasonably rocket-shaped.

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I regret to inform you that there really is no cookie-cutter ascent profile. The nature of your ascent vehicle coupled with the world you are ascending from determines the appropriate flight plan, if any. There are a great many tutorials on this online already and you'll see each tutor seems to focus on different strategies and demonstrations because the ascent vehicles are rarely the same. Here are a some questions I'd have in mind for every build.

Is this thing even aerodynamic? - Doesn't always matter; never hurts to know. Drag can be... well... a real drag. :P Control and lift surfaces in moderation.
Is my center of mass too far aft? - I know the heaviest part of my craft to defeat more drag than the lighter end, almost always forcing it to turn around. Not good.
Am I gonna make it? - If I'm still struggling to make orbit, it couldn't hurt to run a few calculations to find out if my attempt is even mathematically possible.
     "Solve for WHY"

Otherwise notable, it sounds like you're making harsh or sudden adjustments to your trajectory and I'd never recommend that without already being out of the atmosphere. In my experience, any rocketry that flies sideways or backwards in atmo meets a catastrophic end. (Yes, there are super-maneuverable missiles out there, but they usually detonate at some point too.) My advice it to focus on long, slow and deliberate maneuvers. Hotaru gave an excellent example above, but I stand by my previous statement: it's not going to work every time. The idea is to make many small adjustments over a longer period of time. Sometimes leading the prograde vector, other times gently trailing behind it. Each craft will demand at least a subtly different optimized flight plan based on individual characteristics.

Never give up! It's only rocket science! ;) 

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As others have said, there isn't one ideal, "correct" way to do it, but I present one that works in my tutorial. 

 

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To correct your spin around the navball, add (A) SAS and/or RCS on your center of mass, to rotate your ship around its middle, and (B) add aerodynamic parts as far down on the rocket as you can get them, to make it harder for spins to start.

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