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Help me! I can’t get in a stable orbit


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  1. Have you reviewed any of the YouTube tutorials for beginners?  Or stepped thru the Tutorials provided in the game? 
  2. Can you please clarify what you mean about crashing "a few days after launch?" Unless your Apoapsis is millions of km's out (between Mun and Minmus?), a typical low , circular orbit is going to be somewhere in the neighborhood of an hour in duration. 
  3. The typical method is: launch to 90 degrees and try to get to an angle of ascent of about 45 degrees by the time you get to ~20km
  4. Continue to accelerate until the apoapsis is around 80km, then cut the engines and continue to coast
  5. While coasting, go to map view and set a maneuver node at the Apoapsis  and extend the prograde widget until the Periapsis is going to be above  70km
  6. Align with the maneuver point on the navball and begin your burn when your 'burn time' is 50% out from the node (for example, if the burn time is 30 seconds, begin the burn itself at T-15 seconds to node) 
Edited by maddog59
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26 minutes ago, maddog59 said:
  1. Have you reviewed any of the YouTube tutorials for beginners?  Or stepped thru the Tutorials provided in the game? 
  2. Can you please clarify what you mean about crashing "a few days after launch?" Unless your Apoapsis is millions of km's out (between Mun and Minmus?), a typical low , circular orbit is going to be somewhere in the neighborhood of an hour in duration. 
  3. The typical method is: launch to 90 degrees and try to get to an angle of ascent of about 45 degrees by the time you get to ~20km
  4. Continue to accelerate until the apoapsis is around 80km, then cut the engines and continue to coast
  5. While coasting, go to map view and set a maneuver node at the Apoapsis  and extend the prograde widget until the Periapsis is going to be above  70km
  6. Align with the maneuver point on the navball and begin your burn when your 'burn time' is 50% out from the node (for example, if the burn time is 30 seconds, begin the burn itself at T-15 seconds to node) 

 

1. I did tutorials, I still have a hard time 

2. I don’t think it was “in orbit” the right way, some type of not high enough or something like that

3. thanks for the tip of 45 degrees

4. I was using solid boosters, so should I use liquid?

5. I did not know you could do that anywhere other than the tracking station 

6. I can’t use the nav ball, it’s too confusing on the point of the pilot can’t do nodes until certain levels. 
 

thanks for the tips, I will put them into practice later today.

 

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1 hour ago, MrWookie2U said:

4. I was using solid boosters, so should I use liquid?

5. I did not know you could do that anywhere other than the tracking station 

6. I can’t use the nav ball, it’s too confusing on the point of the pilot can’t do nodes until certain levels. 
 

thanks for the tips, I will put them into practice later today.

 

The size of the solid boosters depends on the load ...  since you can't turn them off or throttle them once you light them, they need to burn up and be discarded so you can coast up to Apoapsis. They're mainly good for getting a heavy load off the ground and moving, but shouldn't be the primary means of getting to orbit (yes, there are plenty of examples of people using them  to demo their god-like abilities to manipulate the program, but I'm speaking as a generalist).  You'll want to focus on being able to use liquid stages to get to orbit so you can turn them off and on to adjust your orbit.

 Tap the 'M' key to toggle between Map view (where you can set maneuver nodes) and the flight view of the ship itself. 

As for the NavBall ... you'll need to learn how to use it to make any progress in the game, so I recommend you review the tutorials and see how it's works. It's actually pretty straight-forward, and with SAS turned on ('T' key) even a green pilot can get a ship into and out of orbit and even dock.  I'm pretty much an idiot myself when it comes to flying, so if I can figure it out, I'm sure you can as well! I went thru several of the tutorials multiple times. 

Keep at it and you'll get there.

Edited by maddog59
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Also add note, I have helped tutor the heck out of a relative once and something you will wanna know is that, practice makes perfect. The more launch attempts you do the better, guides will point you in the right direction for sure.

Other notes:

On 1/15/2021 at 10:30 AM, maddog59 said:
  1. The typical method is: launch to 90 degrees and try to get to an angle of ascent of about 45 degrees by the time you get to ~20km
  2. Continue to accelerate until the apoapsis is around 80km, then cut the engines and continue to coast

These two are debatable points. you can start being at 45 at 10km and you really only for first launch attempt cut off at 75km.

 

Here are some stuff that wasn't mentioned in either pieces of advice I think are important:

-Go gradual, then aggressive. don't start turning to the 45 until you have a good speed 70-90 meters per second I would say at least, you gradually want to get to that 45 degree angle, getting the right gradual change takes practice. After 40 kilometers or so, you can start getting aggressive. 

-SAS is your friend. you might notice other marker nodes on the nav, these are very useful, especially the maneuver marker, when making a maneuver, it tends to be a good idea to click the manuever node to have an auto alignment. Now, take it with caution, it will follow it very precisely,  so I would recommend doing the last 2-1 seconds without the auto-align.

of course, @maddog59 and @Vanamonde have given you some good advice. So combine the great knowledge and you should be good after practicing a couple of launch attempts

I also noticed, welcome to the forum :) 

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Well, @maddog59 , @Vanamonde, and @The Doodling Astronaut gave great advice, but they forgot a few key things. 

1. Make sure you pack more fuel than you need, without it seriously affecting CoM or TWR. 3-700 m/s should be good. 

2. If you want an easy orbit, just point 90* up till 10km, then gradually pitch to 45, once you reach 70km, you want to be more or less horizontal. Proceed to burn prograde in map view, (Press M, and use the hotkey to toggle the Navball in Map view) until your periapsis is above 70km. By then your Apoapsis should be above 70km.

3. The extra fuel is buffer fuel/ return fuel, so make sure it is at your final stage (before command module). I use the extra fuel to make corrections, or point retrograde and burn to bring me under a 70km periapsis. I hardly leave anything in LKO at a decent velocity (escape velocity is like 2250m/s) so it is plenty enough to get my Pe lower than 70km, where I can either aerobrake, or just burn retrograde further lowering my Pe, and sending me homeward.

:prograde:= prograde (forward from direction of travel)

:retrograde:=retrograde (backward from direction of travel)

:maneuver:=manuver direction

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Others have posted some pretty good gouge on how to get to a stabilized orbit, but I'm going to respond with my own technique. Please note that it is technique only as there is a million ways to skin this cat. Note: I HIGHLY recommend starting a science mode as a beginner or sandbox, but NOT a career mode. Science mode allows you to create maneuver nodes as a default setting without have to earn that capability. Maneuver nodes are your friend.

1. Build a two stage rocket that has two stages, each with engines. (Preferred that both engines have vectoring for easy steering.

2. The rocket has 3500 m/s Delta V(4000 m/s if you need it for practice) total with around 2.00 TWR for the first and second stages. I recommend staying away from solid rocket boosters(unless you have a third liquid fuel engine that can steer you with vectoring during the launch stage). Ensure this is verified as being used in an atmosphere, not a vacuum.

3. Next, active SAS and then Launch. At around 100 m/s, begin your gravity turn (steering) toward 90 degrees. This will save Delta V.

4. Strive to reach 75 degrees by 5000m, 45 degrees by 10000m, and then continue the turn until you reach 30 degrees and hold.

5. When the Apoapsis reaches 75-90km, cut the engine(s) off. Create a maneuver node at the Apoapsis and drag the Prograde node out until the planned trajectory is a circularized orbit.

6. Watch the timer tick down and start the burn at 1/2 the total burn time required. (Ex: if the total burn is 1 minute, start the burn at 30 seconds prior to when KSP tells you to start the burn. Burn for the full minute in this case and cut off the engine(s). This should get you close to a circularized orbit.

Again, technique only. I like to play a bit conservative so I usually have a circularized orbit around 90km IF i am staying within the Kerbin system. If you want to travel outside the Kerbin system, I recommend using an apoapsis of around 80km for better Oberth Effect(don't worry about that until after you are ready to venture to other planets).

Edited by Nut Slide
Forget to talk about SAS.
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On 1/15/2021 at 11:57 AM, MrWookie2U said:

I was using solid boosters, so should I use liquid?

5. I did not know you could do that anywhere other than the tracking station 

6. I can’t use the nav ball, it’s too confusing on the point of the pilot can’t do nodes until certain levels. 

Liquid is your friend for a main engine set, think Soyuz, Saturn's 1 and 5, Atlas, Titan 2. Solids are to be used at the lowest level with your mains as a way to assist you, but even then, a set of strap on liquids asparagus-staged will work better (mostly).

Yes, you can access the map in flight, the devs aren't that cruel to us. 

Well, the Nav ball is your best friend. Just like the M/S, CoM, CoT, and CoL read outs/markers. 

My biggest advice, especially for newer players is to use sandbox or science modes first, get used to the game, see what works and what doesn't, and then  afterwards swap over to a career save. And when you encounter problems, always ask here....... Don't ask a random discord titled "KSP" or something like that..... We had a newer member do that, and he blamed it partly on our and I quote "toxic community"....... 

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