A new "glass cockpit" that increases Shuttle safety by improving the display of key information about ascent and entry mission performance was one of more than 100 significant improvements Space Shuttle Atlantis debuted during its mission to the International Space Station (ISS) in April 2000. The Space Shuttle underwent a major maintenance and upgrade overhaul performed during a 10-month stay at the Boeing Assembly, Integration and Test Center at Palmdale, CA. STS-101/2A.2a was a 10-day trip and the first ISS mission of 2000. It was also Atlantis' first mission since September 1997.