Narrative:

Due to fatigue 14 hour duty day, 9 hours 30 mins overnight and early departure we forgot to obtain our ATC clearance from pre departure clearance. Once airborne we were given our squawk code and received our pre departure clearance.

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Original NASA ASRS Text

Title: B737 DEPARTED PHL WITHOUT IFR CLRNC. LONG DUTY DAY PREVIOUS WITH A SHORT LAYOVER. DEP CTL ISSUED XPONDER CODE AND CLRNC.

Narrative: DUE TO FATIGUE 14 HR DUTY DAY, 9 HRS 30 MINS OVERNIGHT AND EARLY DEP WE FORGOT TO OBTAIN OUR ATC CLRNC FROM PDC. ONCE AIRBORNE WE WERE GIVEN OUR SQUAWK CODE AND RECEIVED OUR PDC.

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.