Hi, hardcore,

You may not be interested in this anymore, but others may, so I'll go ahead and answer it.
I'm using MS Office 2010 for PC, so your version is probably different.
You would select the plane that should change direction first, click on the animations tab to reveal that ribbon. There you click on Add Animation. Scroll down to the last section that says "Motion Paths.". You have a choice of lines, arcs, loops, turns, and custom paths. I think you would want an arc (which you can adjust) or a custom path.
Continue with the remaining planes.