ACR MLG TKOF FROM DCA AFTER THE NOISE CURFEW.

Narrative

MY FLT LEFT ATL FOR BWI. BWI WAS FOGGED IN SO WE GOT INSTRUCTIONS TO DIVERT TO DCA TO TRY TO MAKE THE XB00 TKOF CURFEW. DCA WAS VFR AND WE LANDED ABOUT XA40. AFTER A LOT OF HARD WORK BY THE GND CREW THE ACFT DEPARTED THE GATE AT AROUND XA55 TO TRY TO MAKE THE CURFEW. THE TWR HELPED US OUT BY PUTTING US AHEAD OF A COMMUTER AND WE RECEIVED OUR TKOF CLRNC AT XB00. I VERIFIED THE LEGALITY OF TAKING OFF RIGHT AT CURFEW AND TWR SAID THEY COULD CLR US FOR TKOF NOW BUT NO LATER. WE HAD COMPLETED ALL CHKLISTS AND WT AND BAL SO WE ACCEPTED THE CLRNC AND TOOK OFF FOR SYR WHERE THEY NEEDED THE PLANE BADLY FOR THE NEXT MORNING DEP. I LATER CAME TO REALIZE IN MY NOTES FOR DCA THAT TKOFS WEREN'T PERMITTED AFTER XA58. I MISSED THIS IN MY TKOF BRIEFING BECAUSE TRYING TO MAKE THE CURFEW WE WERE TIED UP WITH CHKLISTS AND OTHER NORMAL PROCS INCLUDING NOISE ABATEMENT PROCS FOR DCA. I FELT THAT SINCE THE TWR CLRED US FOR TKOF AND I VERIFIED THE LEGALITY OF THE TKOF TIME WITH THE TWR WE WERE LEGAL TO TAKE OFF. APPARENTLY THAT ISN'T THE CASE.