The "side" window slides aft in a track. In this pic you can see the starboard one open an inch or so.
For the people *NOT* working in Photoshop, you might want to look here (it's old news! and an older version);
Hi Good People,
It's time to release the GJSmith.net's packaged version of the excellent Milton Shupe and Team's Fleet Freighter 50K aircraft.