Narrative:

We were cleared into position and hold runway 10C pit. We were then cleared for takeoff with a climb to 5000 ft and a right turn. I, as PNF, read all this back. After we had been at 5000 ft for a few moments, tower queried us as to our altitude and why we were there. I told him that we had heard and read back 5000 ft (after double-checking with my first officer). He denied issuing clearance to that altitude (4000 ft is usual for pit departures, but not guaranteed), and handed us off to departure. Departure also queried us as to our assigned altitude and told us not to worry about it. Clearly, someone (or 2 or 3) miscommunicated and/or misheard. Fortunately, no conflicts arose. I should have said 'verify 5000 ft' when issued the nonstandard departure altitude.

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Original NASA ASRS Text

Title: FLC OF A DORNIER 328 OVERSHOT ALT ON DEP CLB DUE TO MISUNDERSTANDING OF ASSIGNED ALT.

Narrative: WE WERE CLRED INTO POS AND HOLD RWY 10C PIT. WE WERE THEN CLRED FOR TKOF WITH A CLB TO 5000 FT AND A R TURN. I, AS PNF, READ ALL THIS BACK. AFTER WE HAD BEEN AT 5000 FT FOR A FEW MOMENTS, TWR QUERIED US AS TO OUR ALT AND WHY WE WERE THERE. I TOLD HIM THAT WE HAD HEARD AND READ BACK 5000 FT (AFTER DOUBLE-CHKING WITH MY FO). HE DENIED ISSUING CLRNC TO THAT ALT (4000 FT IS USUAL FOR PIT DEPS, BUT NOT GUARANTEED), AND HANDED US OFF TO DEP. DEP ALSO QUERIED US AS TO OUR ASSIGNED ALT AND TOLD US NOT TO WORRY ABOUT IT. CLRLY, SOMEONE (OR 2 OR 3) MISCOMMUNICATED AND/OR MISHEARD. FORTUNATELY, NO CONFLICTS AROSE. I SHOULD HAVE SAID 'VERIFY 5000 FT' WHEN ISSUED THE NONSTANDARD DEP ALT.

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.