Narrative:

Came in as flight xx. I departed as flight xy, changed everything in ACARS except flight number. (Thought we were still xx outbound.) requested clearance via pre departure clearance, however, received clearance for flight xx and didn't realize it until we departed. I quickly changed the ACARS and requested correct clearance. No altitudes or headings were different. (No violation of clearance.)

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Original NASA ASRS Text

Title: MLG DEPARTS WITH WRONG CLRNC DUE WRONG FLT NUMBERS USED ON PDC.

Narrative: CAME IN AS FLT XX. I DEPARTED AS FLT XY, CHANGED EVERYTHING IN ACARS EXCEPT FLT NUMBER. (THOUGHT WE WERE STILL XX OUTBOUND.) REQUESTED CLRNC VIA PDC, HOWEVER, RECEIVED CLRNC FOR FLT XX AND DIDN'T REALIZE IT UNTIL WE DEPARTED. I QUICKLY CHANGED THE ACARS AND REQUESTED CORRECT CLRNC. NO ALTS OR HDGS WERE DIFFERENT. (NO VIOLATION OF CLRNC.)

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.