Why is mechjeb not doing the 'transfer to target'? Well, you already did that, first thing! A holmann transfer is a transfer to your target. Best way I've going with mechjeb is to start in your orbit around kerbin, and use the maneuver planner to 'transfer to another planet'. After leaving kerbins SoI, do a 'fine tune closest approach' to make sure you get an encounter. Then just go about your normal routine! The person above talking about making your own maneuver node is definitely good advice. A lot of times, I find I can set up a maneuver node that spends less dV than mechjeb, but still use mechjeb to execute the maneuver. So yea, plain and simple, you already did your transfer Edit: in order to use mechjebs Holman transfer ability, you must be in same SoI. Aka to holmann transfer to moho with mechjeb, gotta be orbiting kerbol. It'll come up with a nice error message if you do it wrong