Narrative:

Returning from a training flight; the pilot flying opened the right window. Immediately after opening the window; the window began to rapidly oscillate because one of the hinges on the top of the window broke. The pilot attempted to close the window and was unable to close it before it broke off the other hinge. As the window flew back with the wind; it hit the side of the aircraft and broke another fixed window on the right side of the plane. The window also struck the outside edge of the right horizontal stabilizer creating a dent in the surface. The window departed the aircraft approximately 7 nautical miles west of the ZZZ airport on the 275 degree radial from the ZZZ VOR. The aircraft was traveling approximately 115 knots when the window broke off. The flight was using 'flight following' with approach.

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Original NASA ASRS Text

Title: Pilot flying a C172 opened the right side window which began to oscillate; then broke free and departed the aircraft. On the way aft it damaged another window and the horizontal stabilizer.

Narrative: Returning from a training flight; the pilot flying opened the right window. Immediately after opening the window; the window began to rapidly oscillate because one of the hinges on the top of the window broke. The pilot attempted to close the window and was unable to close it before it broke off the other hinge. As the window flew back with the wind; it hit the side of the aircraft and broke another fixed window on the right side of the plane. The window also struck the outside edge of the right horizontal stabilizer creating a dent in the surface. The window departed the aircraft approximately 7 nautical miles west of the ZZZ Airport on the 275 degree radial from the ZZZ VOR. The aircraft was traveling approximately 115 knots when the window broke off. The flight was using 'Flight Following' with approach.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.