Narrative:

At FL200 in cruise flight the first officer noticed a flickering light on his side window. As I looked over I observed what looked like a strobe effect at the bottom of his side window. [Upon] further inspection we realized that the window had a growing crack. I immediately grabbed the QRH and looked up window arcing QRH. I turned off the rh windshield heat and the arcing continued and I told the first officer (first officer) to fasten his seatbelt and I was notifying the flight attendants that they needed to take their seats due to a window issue when the window shattered. At this time the first officer completed the rest of the QRH and I was working the radio and notifying dispatch. The first officer showed me the checklist which said that we needed to reduce our speed to 205 KIAS and descend to 8000 feet. I advised this to ATC. ATC cleared us direct to [a nearby alternate] and down to 8000 feet. I called the flight attendant back and advised her of [the deviation to an alternate] with 15 minutes remaining and that we planned to make a normal landing. I gave the normal briefing to the passengers that we were on our initial descent and would be [on the ground] in 15 minutes. We notified dispatch of the event and told them what airspeed and altitude that we would continue on to [the alternate] at. We continued with no further incident. The window shattered due to a crack that formed at the bottom of the window.

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Original NASA ASRS Text

Title: CRJ-900 flight crew reported diverting after the First Officer's windshield arced and shattered in cruise.

Narrative: At FL200 in cruise flight the First Officer noticed a flickering light on his side window. As I looked over I observed what looked like a strobe effect at the bottom of his side window. [Upon] further inspection we realized that the window had a growing crack. I immediately grabbed the QRH and looked up Window Arcing QRH. I turned off the RH windshield heat and the arcing continued and I told the FO (First Officer) to fasten his seatbelt and I was notifying the Flight Attendants that they needed to take their seats due to a window issue when the window shattered. At this time the FO completed the rest of the QRH and I was working the radio and notifying Dispatch. The FO showed me the Checklist which said that we needed to reduce our speed to 205 KIAS and descend to 8000 feet. I advised this to ATC. ATC cleared us direct to [a nearby alternate] and down to 8000 feet. I called the Flight Attendant back and advised her of [the deviation to an alternate] with 15 minutes remaining and that we planned to make a normal landing. I gave the normal briefing to the passengers that we were on our initial descent and would be [on the ground] in 15 minutes. We notified Dispatch of the event and told them what airspeed and altitude that we would continue on to [the alternate] at. We continued with no further incident. The window shattered due to a crack that formed at the bottom of the window.

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.