Narrative:

Flying in an extra 300L; canopy cracked and departed aircraft. Landed at local field. No structural or significant damage. Adhered to instructions and transfered plane to home airport. Not sure what caused the problem; it happened very quickly. It may have been a bird strike; as there are lots of birds in the area. I did not however; find any marks or indications of such. The canopy is a bubble type so it could have been that the object deflected completely off the plane. Had been flying for some time so I know the latches were all locked. Inspection of the hinges and latches did not indicate anything unusal.

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Original NASA ASRS Text

Title: An Extra 300L canopy departed in flight after cracking for reasons unknown since no hinge or structural damage was found.

Narrative: Flying in an Extra 300L; canopy cracked and departed aircraft. Landed at local field. No structural or significant damage. Adhered to instructions and transfered plane to home airport. Not sure what caused the problem; it happened very quickly. It may have been a bird strike; as there are lots of birds in the area. I did not however; find any marks or indications of such. The canopy is a bubble type so it could have been that the object deflected completely off the plane. Had been flying for some time so I know the latches were all locked. Inspection of the hinges and latches did not indicate anything unusal.

Data retrieved from NASA's ASRS site as of July 2013 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.