Problem with orbit training

[Colaris]

I am playing the demo tutorial and I am having trouble understanding about thrusting prograde to alter my orbit. It is telling me to burn prograde again when we reach Apoapsis to raise Periapsis and circularize my orbit but all thrusting does is reduce the size of my orbit making it less circular and I crash into the planet. What am I doing wrong?

Edited February 21, 2017 by Colaris

[WanderingKid]

That means you're burning Retrograde, not Prograde.  The symbol that has the bars like an inverted T, one on top and left and right, is Prograde.  The one that looks like a Y was overlaid on it is retrograde.

Take a look at the images on this page in the wiki, and it will help you:

http://wiki.kerbalspaceprogram.com/wiki/Navball

[bewing]

Alternately, you may have clicked the Navball out of "Orbit" mode. Or you may not have set SAS to "prograde hold". The direction of "prograde" moves as you go around your orbit -- so when you burn prograde at your Pe, you have to point in a different direction to burn prograde at your Ap.

Edited February 21, 2017 by bewing

[Colaris]

Thanks, it never really went into much depth about all that. I'll take another look and check out that link.

 

What I couldn't seem to be able to do was adjust the craft orientation to point towards the correct marker.

Edited February 21, 2017 by Colaris

[Ty Tan Tu]

SAS is your friend. Hopefully these pictures will help you and others.

1. Pro-grade: When facing Pro-grade to your orbit, a burn of your rocket will increase the altitude on the opposite side of your orbit. Notice on the upper right, the SAS is highlighted, meaning you clicked on it and it is selected. On the left, the green Pro-Grade orientation is selected.

2. Retrograde: Retrograde does the opposite it lowers the opposite side of your orbit.

3. Normal: You use Normal to change your plane, i.e. to align with your target so both orbits are at the same angle. When approaching an alignment node that has a negative value, you want to point the opposite direction to Normal to reduce the difference in the angle.

4. Anti-Normal: This is used when the alignment node shows a positive number.

5. Radial Out: This points your ship nose away from the target, i.e. you are going straight down toward the surface. It is useful when landing a lander on something like Mun.

  

 

[Colaris]

Many thanks for the advice, I will try this out although as I previously mention, no matter what buttons I pressed I could not turn the craft at all and re-orientate it.

[sal_vager]

Perhaps you had no electrical charge left, so your reaction wheels could not turn the craft.

If you click the resources button in the upper right it will open and show you how much fuel, oxidizer and electric charge you have remaining.

[Colaris]

1 hour ago, sal_vager said:

Perhaps you had no electrical charge left, so your reaction wheels could not turn the craft.

If you click the resources button in the upper right it will open and show you how much fuel, oxidizer and electric charge you have remaining.

Ah I see. I'll check that out.

[TheKorbinjer]

"Demo" version, the SAS in the demo version doesn't allow you to orient when the SAS is on. Turn SAS on/off with T and orient your craft to where you like, then press T again to hold there. There is no electric charge in the demo version.

Also, RCS is super overpowered in demo.

 

Hope I help you solve your troubles!

Cheers!

 

-TheKorbinger

Edited February 22, 2017 by TheKorbinger

[Colaris]

4 hours ago, TheKorbinger said:

"Demo" version, the SAS in the demo version doesn't allow you to orient when the SAS is on. Turn SAS on/off with T and orient your craft to where you like, then press T again to hold there. There is no electric charge in the demo version.

Also, RCS is super overpowered in demo.

 

Hope I help you solve your troubles!

Cheers!

 

-TheKorbinger

Many thanks, that done the trick and worked perfectly!

[horace]

18 hours ago, Colaris said:

Many thanks, that done the trick and worked perfectly!

wow why u didnt see youtuber play ksp

[TheKorbinjer]

8 minutes ago, horace said:

wow why u didnt see youtuber play ksp

I find when reading things, you can get more detailed information out.

[Colaris]

I'm now having trouble orbiting Mun, my current orbit takes my right through the moon and I can't seem to set a new path that takes my around it.

[WanderingKid]

23 minutes ago, Colaris said:

I'm now having trouble orbiting Mun, my current orbit takes my right through the moon and I can't seem to set a new path that takes my around it.

In general, to avoid a collision, you'll either need to speed up, or slow down, during your approach.  Set a maneuver node by clicking on your orbit, then drag the prograde or retrograde markers until you're not colliding with the Mun.

Once you've done that, you'll have a target marker on your NavBall.  Looks like a blue crosshair.  Aim your ship onto that, and wait until the 'time until burn' in the bottom right of the NavBall is half of your 'estimated burn' listed on the right.  Then go full throttle until you've executed the maneuver (Using Z), then shut off your engines (using X).  That will give you a periapsis you can work with.

From there, on the Periapsis itself, set another maneuver node, burning retrograde.  This will lower your apoapsis so you're actually orbiting Mun once you execute that maneuver.

[bewing]

1 hour ago, Colaris said:

I'm now having trouble orbiting Mun, my current orbit takes my right through the moon and I can't seem to set a new path that takes my around it.

Additionally, burning pure East (or West, or North, or South) will also prevent you from impacting. But you can't easily program East or West into a maneuver node.

[WanderingKid]

6 minutes ago, bewing said:

Additionally, burning pure East (or West, or North, or South) will also prevent you from impacting. But you can't easily program East or West into a maneuver node.

Well, you kind of can with radial/anti-radial, but I was trying to keep it simple.

[Kryxal]

In any case, doing the correction earlier is better than later, and prograde or retrograde work well for that.