Environmental tests of the flight GLAST LAT tracker towers

The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component ( tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental testsperformed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental testsinclude vibration testing, thermal cycles and thermal-vacuum cycles of every trayand tower as well as the verification of their electrical performance.