Narrative:

Just prior to pattern entry a violent windshield failure occurred. At the time of the failure; I was looking down to stow my ipad in the door pocket; which protected my face from the debris. 90% of the windscreen imploded into me and out the left side of the aircraft; taking my hat and headset off. The resulting pressure through the fuselage blew out the left rear window as well. Compass; sunshades; and all other loose items in aircraft departed out the opening. The debris hit left wing and left horizontal tail leading edges; causing some fabric damage. Was able to retrieve headset; make one radio call; and land otherwise normally. Unsure if bird strike; or another object; or if windshield failed on its own accord. Fortunately/unfortunately; I happened to be looking down at the moment of its failure; so I have no idea whether something hit my aircraft or not. There is no physical evidence of a bird; and no parts of a drone or other object. Colleagues of my father (all in aviation) believe it to have been a strike of some kind; as they haven't seen an unprovoked windscreen failure like this before. No injuries; no witness to the moment of incident other than myself.

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Original NASA ASRS Text

Title: Citabria pilot reported the windshield shattered for unknown reasons.

Narrative: Just prior to pattern entry a violent windshield failure occurred. At the time of the failure; I was looking down to stow my iPad in the door pocket; which protected my face from the debris. 90% of the windscreen imploded into me and out the left side of the aircraft; taking my hat and headset off. The resulting pressure through the fuselage blew out the left rear window as well. Compass; sunshades; and all other loose items in aircraft departed out the opening. The debris hit left wing and left horizontal tail leading edges; causing some fabric damage. Was able to retrieve headset; make one radio call; and land otherwise normally. Unsure if bird strike; or another object; or if windshield failed on its own accord. Fortunately/unfortunately; I happened to be looking down at the moment of its failure; so I have no idea whether something hit my aircraft or not. There is no physical evidence of a bird; and no parts of a drone or other object. Colleagues of my father (all in aviation) believe it to have been a strike of some kind; as they haven't seen an unprovoked windscreen failure like this before. No injuries; no witness to the moment of incident other than myself.

Data retrieved from NASA's ASRS site 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.