Narrative:

XX45Z, dca departure frequency, 11000 ft. ATC facility: dca departure. Location: 20 mi southwest of dca. Departing dca, I inadvertently climbed about 400 ft over my assigned altitude of 11000 ft. I saw and heard the altitude deviation warning and immediately descended to the assigned altitude. ATC did not issue a warning that we had deviated from altitude and I am not sure that they were aware of it. The flight proceeded on to ord without further incident.

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Original NASA ASRS Text

Title: A F100 DEPARTING FROM DCA, DC, OVERSHOT ASSIGNED ALT BY 400 FT.

Narrative: XX45Z, DCA DEP FREQ, 11000 FT. ATC FACILITY: DCA DEP. LOCATION: 20 MI SW OF DCA. DEPARTING DCA, I INADVERTENTLY CLBED ABOUT 400 FT OVER MY ASSIGNED ALT OF 11000 FT. I SAW AND HEARD THE ALT DEV WARNING AND IMMEDIATELY DSNDED TO THE ASSIGNED ALT. ATC DID NOT ISSUE A WARNING THAT WE HAD DEVIATED FROM ALT AND I AM NOT SURE THAT THEY WERE AWARE OF IT. THE FLT PROCEEDED ON TO ORD WITHOUT FURTHER INCIDENT.

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.