The Shuttle Mission Simulator (SMS) consisted of two simulators in Building 5 and one simulator in Building 35 of Johnson Space Center. The fixed-base simulators included high-fidelity mockups of the flight deck of a Space Shuttle, as well as a low-fidelity mockup of the middeck. The facility in Building 5 was known as the Fixed Base Simulator (FBS), while the facility in Building 35 was known as the GNS (an acronym for the original name, Guidance and Navigation Simulator). The motion-base simulator consisted of the forward part of the flight deck of the Space Shuttle. It utilized a six-axis hexapod motion system with an additional extended pitch axis to provide motion cuing for all phases of flight.