A quick example of Peg 4 with Thorsten tool applied to Orbiter for deorbit and spherical gravity to start with.
Reminder to the links with tutorials and explanations about the tool
http://www.science-and-fiction.org/science/leo_targeting.html
Scenario tested is "Atlantis in Orbit" from SSU files
I fired Base Sync and waited to have a good crossrange ( here in One orbit, crossrange of 500 km, good)
To define the position of the Shuttle, we need longitude, latitude, Total speed ( Orbital Speed), upward speed ( vertical speed) , altitude and course ( heading when in prograde vector, ie LVLH Yaw equal zero)
We can get those in Surface MFD really quickly
Then we enter them in a config file ( converted for imperial units in my case, but can be in meters with SI units)
For now, we can't set the MET coupled to that position ( Thorsten is editing a fix)
So at the position defined in the file, time is set at zero, like a Base Time in Spec 34
Position in game was at MET 000/06:38:00, so it is our new base time .
Then we enter some value under PEG 4 guidance ( I took STS 30 one's, and adjusted a bit theta angle to have an almost null radial velocity)
Time of ignition is roughly 2700 seconds before KSC like we explained earlier, giving us 00:39:00 mn after the base time, ie. 000/ 07:17:00 in game
And then we run the tool, giving us a burn of 311 ft/s retrograde and 5 ft/s radial upward, for a re entry range of 4200 Nm ish
Solution loaded in MM 302, and quite coherent so far ( perigee targeted of 19 Nm)
Burn time , not too far from our 2700 sec from KSC rule of thumb
And entry range at 4300 Nm at Entry interface.
So really useful in Orbiter for complex Peg 4 calculations and even OMS 1/2 targeting, Rendez Vous planning coupled with Indy FDO tools