2004: Finished Naysmyth telescope (supplied by DLR) mated into the modified aircraft and tested.

2006, April: All major structural modifications to the aircraft completed.

2007, April: First test flights of the Observatory.

2008, January: Closed door testing completed.

2008, June: First coating of primary mirror.

2008, June: Call for white papers for "Short Science" participation.

2008, September: Coated primary mirror delivered to Dryden Aircraft Operations Facility (DAOF).

2008, October: Short Science white papers reviewed, and selections announced.

2009, December: First open door flights.

2010, January: TA activation flight.

2010, May: Telescope Assembly Characterization and First Light (TACFL) flight.

2010, July: "Basic Science" proposal submission deadline.

2010, November: Results announced for "Basic Science" proposal call.

2010, December: FORCAST Short Science observations completed.

2011, April: GREAT Short Science observations completed.

2011, June: FORCAST Basic Science flights completed.

2011, July: First portion of GREAT Basic Science flights completed.

2011, July: Announcement of Opportunity for 2nd Generation Instruments released.

2011, Fall: Call for Cycle 1 observing proposals will be released.

2011, September: Second portion of GREAT Basic Science flights scheduled to begin.

2011, October: Proposals for 2nd Generation Instruments due.

2012, Fall to 2013 Summer: Cycle 1 science flights.