Flight Question auto pilot focus?

seanj

New member
Joined
Aug 16, 2012
Messages
1
Reaction score
0
Points
0
Just started playing this today, trying to figure out how to do a transfer orbit from LEO to polar lunar orbit. I figured out how to do a relative plane align and a holmann transfer orbit, however my auto pilot switches focus from the earth to the sun in route so I am having trouble aligning for the lunar plane shift in route or doing a retro-grade burn for lunar capture. How do I change the focus on my auto pilot? I'm sure i am missing something obvious
 
which autopilot are we talking about here? There are a few that are better for Earth -> Moon, things like LTMFD and IMFD for example.
 
First: Welcome here ! :salute:
Secondly, the thing switching reference from the Earth to the Sun is your HUD, where primary informations are displayed. The reference changes because you leave the Earth's major gravity sphere, called SOI (by Sphere Of Influence). Since the Moon has not a very large SOI, the reference changes from the Earth to the Sun, and when you arrive close to the Moon (and enter inside it's SOI), the reference changes. So to force the reference to Earth, open an MFD, select Orbit MFD, click on "REF" button, select "Earth" (using arrows and Enter) and then click on the "HUD" button. Now the HUD has been updated and correctly referenced to the Earth.

Let me tell you more things to do an easier Earth <-> Moon transfer: Lunar Transfer MFD.
Does all by it self, even aligning up the orbit with a base or planified coordinates. For others transfers, i recommand you IMFD, avaliable on the same page.

Hope you will make and enjoy your flights !
 
I suspect he is talking about the "built in" stock autopilots - prograde, normal, etc.

These AP's will ALWAYS reference the dominant gravity source, and this can't be changed. For most moon trips, this is a minor inconvenience. You should be close to aligned with the Moon before you make the transfer burn, and your first MCC's will be made while you are still in the Earth's SOI. If you need to make an adjustment while you are in the Sun's SOI ic can get a bit trickier. Teh Normal and Anti-normal AL's will still work OK since you should be close to aligned with the Moon, which is fairly close to the Ecliptic. The Prograde and Retrograde AP's won't be much use while in the Sun's SOI.

To make Prograde or Retrograde burns while you are in the Sun's SOI, open an OrbitMFD, and set the Ref to Earth, then press HUD. Now, the HUD is showing you your orbit relative to Earth, and you can manually point at the Prograde or Retrograde indicators.

For the lunar insertion burn, you will be inside the Moon's SOI by then so the Autopilots will be referenced to the Moon - which is exactly what you want.
 
Back
Top