Practically any book with the word ""airplane"" or ""fly"" in the title will sell to smell fry today. This is a ""pretend"" book, and as such, reasonably successful, though the content is not particularly original. Two youngsters pretend, not that they are birds or bugs or bees, but that they are going up in a plane, seeing the things they'd like to see from a plane, and coming down by parachute. Pictures and text are intimately linked, in somewhat comic strip style, and the pictures look the way children think their own drawings look, highly simplified, but orderly and colorful. Lucienne Bloch has done a job the children will like.