Banyon is part of a shuttle mission where NASA is trying to improve their image by sending an average Joe (Homer) into space. Banyon is one of the minor characters in the series but he is still a big fellow. Banyon is generally impatient and condescending towards Homer. When an emergency develops during the mission and it looks like they all are going to die, Banyon declares that he is taking Homer to hell with him.
It is possible Banyon's name was influenced by a Jonny Quest character and Pace Mannion, who played six years in the NBA for several teams.