I don't remember exactly how it works, but if you go into one of the side cabin doors, there'll be a generator thingy. Switch it on. Then you go out of the room while the person in the next room goes in to the room with the machine. Then, go into the room that he left from, where you'll find the invisiable machine part (forgot which that was) Then, you ca make yourself invisible as you walk through the large cargo area and pick up your stuff. I hope I was helpful!