An electronics chassis is provided that utilizes multiple fan units, each of which may incorporate multiple fans, to improve airflow through an internal enclosure of the chassis. Various combinations of multiple fan units are utilized to increase airflow and provide redundancy in the event of the failure of one or more fans. In one arrangement, combinations of horizontally mounted and vertically mounted fans are utilized to improve airflow. In further arrangements, multiple access openings are provided into the enclosure such that an individual fan unit or an individual fan may be accessed for servicing purposes without altering or discontinuing the operation of other fans or fan units.