Maggie's airplane is a Cessna 170 and its windows are hinged at the top as seen when Joel is getting out at Soapy Sanderson's place. Later in the episode while Joel is pouring out the ashes, he unlatches the window at the top and the window hinges at the bottom like a Piper Cub.
The quote attributed to Chief Seattle actually came from a screenplay by Ted Perry in the 1970s.