SOFIA in operation: status of the telescope in-flight commissioning

After 8 years of development, the telescope of the Stratospheric Observatory for Infrared Astronomy, SOFIA has been integrated into the aircraft and has just started with the first observation test flights. Due to its rather unique environment in the open port of a Boeing 747SP, the telescope optics of SOFIA is exposed to extreme aero-acoustic excitations. The telescope pointing system is equipped with several design features, such as a vibration isolation system, a flexible body control system and - potentially - active mass dampers, to handle excitations in different frequency ranges. Final performance features of these systems will only be available after the first test flights, which will happen in the first half of 2010. A progress report is presented and describes the recent achievements as well as the status of the telescope, and gives an update of the SOFIA pointing system, and the planned commissioning tests.