Narrative:

Passing through 100 KIAS during takeoff; I heard a pop sound and noticed that several large cracks had formed in the captain's L2 window. We continued the takeoff. Passing through approximately 2500 ft MSL; I heard another pop sound and noticed that more cracks had formed in the window. We also received a window overheat indication for the window. At this point we decided to level off at 5000 ft while we ran the checklist for window damage and window overheat in the QRH. [Landing priority was given] by ATC while we were in the process of analyzing the situation. We noticed that the size and lengths of the existing cracks were continuing to increase and that they had formed in the outer pane only. We determined that the safest course of action was to air return to [our departure airport]. We returned for the ILS; landed; and taxied to the gate uneventfully.

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Original NASA ASRS Text

Title: B737 Captain reported extensive cracking in his cockpit window; resulting in a return to the departure airport.

Narrative: Passing through 100 KIAS during takeoff; I heard a pop sound and noticed that several large cracks had formed in the Captain's L2 window. We continued the takeoff. Passing through approximately 2500 ft MSL; I heard another pop sound and noticed that more cracks had formed in the window. We also received a Window Overheat indication for the window. At this point we decided to level off at 5000 ft while we ran the checklist for Window Damage and Window Overheat in the QRH. [Landing priority was given] by ATC while we were in the process of analyzing the situation. We noticed that the size and lengths of the existing cracks were continuing to increase and that they had formed in the outer pane only. We determined that the safest course of action was to air return to [our departure airport]. We returned for the ILS; landed; and taxied to the gate uneventfully.

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.