Narrative:

Aircraft was climbing to 5000 ft on autoplt while I was tracking the 185 degree radial off of dca in heading mode. Going through 4300 ft MSL, the aircraft was climbing at over 4300 FPM. I disconnected the autoplt to hand fly the level, in fear that the autoplt was going to climb through 5000 ft. I leveled the aircraft off at 5000 ft and managed speed did not slow the aircraft at 250 KIAS. The autothrust stayed in a climb power setting and the airspeed climbed to 280 KIAS before the autothrust was disconnected and the speed brought back to 250 KIAS. We were above 250 KIAS for no longer than 10-15 seconds. ATC did not say anything, and no altitude or lateral deviations took place. The rest of the flight progressed normally.

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Original NASA ASRS Text

Title: A320 FLT CREW EXCEEDS 250 KTS BELOW 10000 FT DURING DEP FROM DCA.

Narrative: ACFT WAS CLBING TO 5000 FT ON AUTOPLT WHILE I WAS TRACKING THE 185 DEG RADIAL OFF OF DCA IN HEADING MODE. GOING THROUGH 4300 FT MSL, THE ACFT WAS CLBING AT OVER 4300 FPM. I DISCONNECTED THE AUTOPLT TO HAND FLY THE LEVEL, IN FEAR THAT THE AUTOPLT WAS GOING TO CLB THROUGH 5000 FT. I LEVELED THE ACFT OFF AT 5000 FT AND MANAGED SPD DID NOT SLOW THE ACFT AT 250 KIAS. THE AUTOTHRUST STAYED IN A CLB PWR SETTING AND THE AIRSPD CLBED TO 280 KIAS BEFORE THE AUTOTHRUST WAS DISCONNECTED AND THE SPD BROUGHT BACK TO 250 KIAS. WE WERE ABOVE 250 KIAS FOR NO LONGER THAN 10-15 SECONDS. ATC DID NOT SAY ANYTHING, AND NO ALT OR LATERAL DEVS TOOK PLACE. THE REST OF THE FLT PROGRESSED NORMALLY.

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.