On November 29, 1961, the chimpanzee Enos made two orbits for the Mercury MA-5 mission. MA-5 was the first orbital mission by an American primate. Because of a malfunctioning control jet and an overheated inverter, Enos was brought down after two orbits, instead of the three that were originally planned for the mission. MA-5 met its two primary objectives, testing the spacecraft's environmental control system and the procedures for recovering an astronaut, and thus was considered a complete success. It paved the way for the first manned orbital flight, MA-6, by John Glenn in February 1962.