Career rover carrier

Last changes:
-Small ramp added to make it less likely the rover gets stuck inside.
-improved landing code that saves the target and returns to it when turning off AG3


For the career rover missions to Luna or Brigo, this is a rover carrier vehicle with a fair deal of automation.

To use: Choose heading 90 to launch, stage for autoascent. Once in orbit, stage to detach the launcher (the main rocket stage is recoverable, just deorbit and keep 150 m/s of dV so the powered landing program can function - AG3 to run it)

With the carrier, manually transfer to Luna or Brigo, deorbit to drop where you need, activate the landing program (AG3) to assist. the side drop tanks detach automatically.

Once landed, use AG2 to open the ramp and the rover will automatically detach.