Narrative:

Departed without pre-departure clearance. Got it during climb. No deviations.

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Original NASA ASRS Text

Title: B737 FLT CREW DEPARTS WITHOUT CLRNC AND ACQUIRES IT AFTER TKOF FROM ORD.

Narrative: DEPARTED WITHOUT PRE-DEP CLRNC. GOT IT DURING CLB. NO DEVS.

Data retrieved from NASA's ASRS site as of July 2007 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.