The Universal Mobility Incorporated UM III people mover was installed in 1991 when the new long-term-parking garage was built and opened on December 16. It was the first of its kind in the world to include six driverless, electrically propelled cars that are completely computer controlled. The system was also the first to have active switches and it was monitored from the airport's communications center. There were four stations in the long term parking garage, and three in the short term parking garage. The Monorail circled the long-term-parking garage and connected to the short term garage via an elevated bridge to stop at four additional stations. The Monorail was free to use and ran 24 hours a day except for a once-a-week maintenance shut-down in the overnight hours. Bombardier Transportation maintained the system by contract and the Aviation Authority owned it. Thales Rail Signalling Solutions won a contract in 2008 to completely upgrade the computer control system. The upgrade was implemented and tested for an entire year. The only visible change to passengers were the station graphics which show the position of each monorail car and display system status information. In early 2020, the monorail was permanently closed.