Nope, not a green screen effect, it's the real thing. I had a hard time with it at first myself. I think it partly has to do with the overcast sky and lack of shadow from the plane, makes it look funny. However, I took the file into Adobe Premiere and looked at several parts of it frame by frame, with setting the contrast right you can see the shadows and there are a few parts that would be next to impossible for them to have done, unless they work for a Pixar type company for their day jobs. On the first video there is a part at 2:02 were you see a yellow plane with a few people standing next to and near it. Back up a few frames from there at about 1:59 and you can see the reflection of the plane/people on the covering of the underside of the wing as it rolls around before flying over the camera. There are several other points where the covering reflects objets on the horizon and Mr. Sebastiano himself.