[G][Moon] orbit is unstable

[Fixerger]

So I have DG and the orbit near the Moon (Alt 80km, Ecc 0.0000), my orbit is synced to Earth orbit. But this nice(?) orbit is stable for short period of time. After 24hrs ecc goes from 0.000 to 0.350, Pea near 10km.

What is it? Earth influence? o_0 How I can reach real STABLE orbit for moon to rotate like ISS (is it possible?)

 

[garyw]

Mascons

I think there is an option in the launchpad to turn off the complex gravity model.

 

[insane_alien]

well, from real probes sent to the moon, your orbit is not going to be stable unless your orbit is sufficiently high. even then its still going to be wobbling all over the place. while the moon is pretty sperical, its gravitationally lumpier than school custard.
your options are low and short lived or high and long lived.

 

[Fixerger]

I've tried to desync orbit of DG and Earth and change for 90deg. But it did not help even on 1000km orbit. Maybe a little but still very unstable %)

 

[garyw]

I have no idea what that means.

 

[Fixerger]

Oh wait o_0 I'm turned on PROGRADE and my orbit si stable now. But WTF???? Why I can't fly stable without it???

 

[garyw]

What do you mean by "stable"? Screenshot of the problem might help.

 

[Fixerger]

I make simple screenshot http://funkyimg.com/u2/638/163/1.png (Prograde on - orbit stable, prograde of - unstable)

 

[insane_alien]

links broke, apparently the server has been taken offline due to criminal activity.

 

[garyw]

Attach the screenshot to the posting.

---------- Post added at 14:37 ---------- Previous post was at 14:36 ----------

By stable do you mean a stable attitude? If so, try out attitude MFD.

 

[Fixerger]

Stable Ecc (PeA and ApA is +/- for a little but stable).

 

[garyw]

I can't see a problem there. the orbit is stable. Again, I'd suggest Attitude MFD

 

[Fixerger]

I've tried to record with Flight Data monitor but Orbiter always crashes with it. This screen shows how need to be (stable orbit with turned prograde button). When i disable this button my DG every circle loose ECC for some value. Every circle I loose **km of PeA, and after 24hrs it falls. Why prograde mode makes my orbit much stable (ecc is very low)???

 

[Fixerger]

Attached my scenario with weird things.

In short: on the same accel (10x) i got no change of ECC with prograde button enabled for more than 5000sec. But have ECC +0.0001 with prograde disabled and after 1300sec...

CPU load is 30-70%

 

[the.punk]

Weird. I have the same problem with your scenario. Orbit is so unstable.
I tried one of my scenarios. And there I have no problems.
I hadn't this problem before. Only with your scenario.

 

[martins]

Attached my scenario with weird things.

In short: on the same accel (10x) i got no change of ECC with prograde button enabled for more than 5000sec. But have ECC +0.0001 with prograde disabled and after 1300sec...

CPU load is 30-70%

The scenario indicates that the thrusters are active (line THLEVEL in the GL-01 section).

THLEVEL 4:0.001 5:0.001

Can you please turn off the thrusters (e.g. by removing that line) and try again (after making sure that you don't apply any residual input e.g. from joysticks, and that no autopilot settings are engaging thrusters)? You can also empty the tanks to make sure that no input devices or autopilots can activate the thrusters.

 

[the.punk]

Ah. Yes. I was also thinking of that.

 

[Fixerger]

Ok. I've removed this line and my orbit is now stable! (ecc is still 0.0001 after 7000sec).
It seems to be a bug with thrusters... coz I always use * button to disable engines because was having trouble to setup it by Ctrl+/- (LED shows only 0.0) %)

---------- Post added at 08:52 PM ---------- Previous post was at 08:36 PM ----------

More info: I've started from the moon after the original Earth to Moon demo scenario was ended (but don't remember exactly and saved game several times).

Also, I have bug with incorrect resolution in fullscreen. I've set 1280x1024 but for first time it loads some like 1280x720

---------- Post added at 08:55 PM ---------- Previous post was at 08:52 PM ----------

And all savegames has this THLEVEL 0.001 value

 

[martins]

Can anybody confirm this? I can't reproduce it, either with the release version or the beta. Lunar orbits seem to be rock solid for at least several days, at time acceleration 1000, and I don't get any residual thrust levels in the saved scenarios.

Are you certain that this isn't caused by a joystick with a too narrow deadzone on the throttle?

 

[Fixerger]

I dont have a joystick Also, does DG in this scenario has front thrusters? o_0 because I can press ctrl - and will have negative value. But on another scenario I can't use this feature.