OrbitMFD Apoapsis and periapsis both rising

[DrEStrangelove]

After circularising my orbit, I've noticed that the orbit MFD broke - times required to reach the periapsis and apoapsis are constantly rising, approximately at the same ratio, with no thrust at all and altitudes remaining just the same. How is it even possible? I wanted to lower my periapsis, but the apoapsis keeps moving further and further away.

 

[dbeachy1]

Check whether you have "Nonspherical gravity sources" and/or "Gravity gradient torque" enabled in the Parameters tab in your Orbiter launchpad. Both of those realism options can perturb your orbit slightly.

 

[Urwumpe]

After circularising my orbit, I've noticed that the orbit MFD broke - times required to reach the periapsis and apoapsis are constantly rising, approximately at the same ratio, with no thrust at all and altitudes remaining just the same. How is it even possible? I wanted to lower my periapsis, but the apoapsis keeps moving further and further away.

Sounds rather propulsive to me, the moon could also do this to your apoapsis and periapsis, but should also increase altitude over time, until you reach a tipping point and the motion reverses.

 

[Buck Rogers]

If the altitude is not changing is your orbit circular, Eccentricity=0? In which case your Peri., Apo will be constantly changing i.e. you can burn whenever you want.
Otherwise I have had with Orbiter2016 several times an increasing Apo. without thrust, appears to be a gravity problem; Orbit MFD shows G:#, had to exit and reload, problem gone. I think I was using D3d9 but I haven't been able to isolate the problem yet.

 

[DrEStrangelove]

Looks like it must have been a bug, reinstallation of the sim and all addons solved the issue.