Flying explanation for a very big Idiot.

[lasersword]

Hi, I play kerbal now since some months and never even got to Mun without the use of cheats. I can go in an orbit around Kerbin but only with luck, and if I'm in an orbit It is 1:3 Periapsis:Apoapsis. 

Also I then have no more fuel... 

What am I doing wrong? Or more specific: how to do it right? 

I try to get a very high Efficiency with my engines and a good TWR but I still run out of fuel, explode on the launchpad etc.

Is this still part of the learning process? Or am I learning wrong? 

I would be very happy about some help. 

-Lasersword 

[bewing]

I would say that you need to learn how to get to orbit repeatably, before you can improve your technique to do it "right". Have you watched the youtube videos explaining how to get to orbit? Or done the tutorial in the game?

Once you are in orbit, getting to the Mun is really just a matter of understanding all the tricks of how to set a maneuver node. Even in a rocket with no fuel, you can still set a maneuver node, and experiment with it, and see how it works. Have you done that?

[lasersword]

24 minutes ago, bewing said:

I would say that you need to learn how to get to orbit repeatably, before you can improve your technique to do it "right". Have you watched the youtube videos explaining how to get to orbit? Or done the tutorial in the game?

Once you are in orbit, getting to the Mun is really just a matter of understanding all the tricks of how to set a maneuver node. Even in a rocket with no fuel, you can still set a maneuver node, and experiment with it, and see how it works. Have you done that?

I watched different YouTube videos and also read the wiki page about orbiting, I for example fail to know when to deaccelerate, turn etc. If I do it like it is shown in a YouTube video I don't have the remaining fuel to stabilize my orbit... 

But thanks. I'll continue my trying... Kerbalkind will never forget those hundreds of thousands of dead kerbals that helped increasing the knowledge of Space, heat resistance of kerbals, fuel needed to not burn up etc. 

But seriously, thanks for the Tip with the maneuver nodes. 

[bewing]

It sounds like you do basically understand, then. You go up, you turn east. You burn until your Pe is above 70km. If the Ap starts getting too far in front of you, you coast for awhile, and when it gets close again you burn some more. If you pass the Ap, then just burn until your Pe is over 70km (you can point the nose up a little for extra points).

If that's what you're doing, then all you need is more fuel in your rockets.

Edited July 7, 2016 by bewing

[lasersword]

7 minutes ago, bewing said:

It sounds like you do basically understand, then. You go up, you turn east. You burn until your Pe is above 70km. If the Ap starts getting too far in front of you, you coast for awhile, and when it gets close again you burn some more. If you pass the Ap, then just burn until your Pe is over 70km (you can point the nose up a little for extra points).

If that's what you're doing, then all you need is more fuel in your rockets.

I'll try that, I would say that this question has been solved as far as it was possible to solve it...

I also got confused about When to burn where. This explanation looks far simpler. Thanks

-Lasersword 

[Warzouz]

There are 2 reasons you can fail

• Your flight technique is flawed (or need optimisation)
• You rocket design is flawed (TWR, dV...)

I would recommend you to practice with Stock Kerbal-X in sandbox game. It's an easy rocket than can go to the Mun, land and come back with more than 500m/s of spare fuel. Then you can go to Minmus (with even more spare fuel left).

If you have a hard time flying/landing, there are some mods that can help you (MechJeb). Look at what autopilots do, then you can try it yourself.

If you have a hard time designing rockets KER mod can help you (MechJeb too). Or use stock rockets and try to understand how and why they are built that way.

Edited July 7, 2016 by Warzouz

[Hodari]

If you haven't already done so, I'd also suggest getting Kerbal Engineer Redux(or Mechjeb or any other mod that shows your rocket's delta-V).  This way you can at least know that theoretically your design should be able to get where you want it to.  Then just figure out how much dV you need for various types of missions.  If you're really efficient about it, 3500 is probably enough for low Kerbin orbit, though I'd allow at least 4000 for now.  7000 should be enough to do a Mun/Minmus landing and return or for at least a flyby of another planet.  If you search for "delta v map" you should find plenty of them showing exactly how much dV you need(those are minimum values though, so bring extra).  But definitely practice getting into orbit efficiently first before trying to go any further. 

[lasersword]

22 hours ago, bewing said:

 

OK thanks to everyone here. I yesterday searched some of the terms used here (the foeum) of which I didn't know what they mean, i also searched for the term Delta V but didn't find any up to date maps. And I heard there were several changes in drag etc. Over the versions. 

Thanks to everyone. 

-Lasersword 

[FyunchClick]

18 hours ago, lasersword said:

i also searched for the term Delta V but didn't find any up to date maps.

Try googleing 'kerbal dv map 1.1.3'. Or whatever the current version of kerbal is at the moment. Here's the current one:

 

[lasersword]

4 hours ago, FyunchClick said:

Try googleing 'kerbal dv map 1.1.3'. Or whatever the current version of kerbal is at the moment. Here's the current one:

 

Thank you very much

Edited July 9, 2016 by lasersword

[Madscientist16180]

I concur with those saying that in the situation, if you do not already have one, get a mod the will give you DeltaV (delta meaning difference and V standing for velocity, so basically deltaV is the measure of him much your craft can change velocity, either up or down). As any single change in your projected orbit is achieved by somehow altering your velocity, it is the most important info to have while designing. TWR is also pretty important (thrust-to-weight ratio). Knowing TWR allow you to put just enough engine power, too little and you won't leave the pad (TWR<1), too much and you'll go too fast too soon and risk busting in flames before your high enough (TWR>let's say 2.5 anybody can chime in on this? I never built high TWR rocket so do not really know for sure). 

If you use SRB (solid rocket boosters), you should account for the fact your TWR si go up as they burn out, and you cannot do anything about it. With LFO (Liquid fuel+oxydizer) engine, having too much TWR can be compensated by throttling down.

IMO, à good way to learn how to get to orbit efficiently is to:

• Launch a rocket with 4500 deltaV and TWR of 1,3 or so at launch.
• Engage SAS at launch
• When you get a speed of +/- 80 to 100m/s turn your rocket east about 10 °. When your actual heading and prograde marker stabilise together, lock SAS to prograde. 
• From there, using LFO engine, try to have TWR of about 1,75 when you get to 10km.
• The tricky part is now to let the prograde marker, and thus heading, sink to the east toward the horizon. It take some trial and error to get the feel. If by the time you reach 35 km, you are well under 20°, you sank it too fast (TWR was kept too low), if it is over 25/30°, you sank it too slow (TWR was kept too high). The latter situation is less problematic, just less efficient, while the first situation is more critic, if you do not get the apoapsis over 70km before going over it, you won't get to space!
• By 40/45 km, your apoapsis should get near 60km high, and you should start thrusting directly to the horizon to get the periapsis as high as possible before reaching your desired cirularization altitude.

KER (Kerbal engineer redux) is in my opinion the best mod to have all the relevant info, as it display TWR in a dynamic way, Imagine your Twr at full throttle is 3 and you are at half throttle, the display would be TWR 1,5/3. Pretty useful in my opinion.

In the best of worlds, you rocket should do most of this without needing much input, more less SAS, but to get the hang of it, this technique helped me. You'll find yourself with more and more fuel left in orbit as you fine tune your piloting and design and one day, you'll be happy to be able to do it as efficiently as the best youtuber out there! 4500 DV, when used efficiently, could one day allow you to at least fly-by the moons.

Edited July 10, 2016 by Madscientist16180