Narrative:

On takeoff at msy, our initial clearance was 'maintain runway heading and climb to 4000 ft.' when the tower handed us off to departure, the departure controller gave us a right turn to 080 degrees and cleared us to climb to 15000 ft. The captain read back the clearance and put 15000 ft in the altitude preselect. I read back 'right turn to 080 degrees, climb to 15000 ft' to the captain. Just as we were climbing through approximately 11300 ft, the departure controller called us and said 'maintain 11000 ft' with an admonishing tone in his voice. I quickly reduced power and pushed the nose down, at which time our altitude had peaked at about 11000 ft. Both of us are certain that we were cleared to 15000 ft and both of us are certain that we didn't get an amendment to our clearance. As we were trying to figure what had just happened, the departure controller handed us off to ZHU. I think what probably happened was that new orleans had special procedures in effect at the time because of a special event. We were probably cleared to 15000 ft in error and it was not noticed until we were obviously climbing through 11000 ft. Supplemental information from acn 537370: no other traffic was involved. Neither of us could recall the standard departure altitude at msy. We were left with the impression this was a non event, but you never know.

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Original NASA ASRS Text

Title: A300 FLC ARE ISSUED HDG AND ALT CHANGE AT TIME OF COM XFER FROM MSY TWR TO DEP CTL AND ARE CHALLENGED WHEN OBSERVED CLBING THROUGH 11000 FT.

Narrative: ON TKOF AT MSY, OUR INITIAL CLRNC WAS 'MAINTAIN RWY HDG AND CLB TO 4000 FT.' WHEN THE TWR HANDED US OFF TO DEP, THE DEP CTLR GAVE US A R TURN TO 080 DEGS AND CLRED US TO CLB TO 15000 FT. THE CAPT READ BACK THE CLRNC AND PUT 15000 FT IN THE ALT PRESELECT. I READ BACK 'R TURN TO 080 DEGS, CLB TO 15000 FT' TO THE CAPT. JUST AS WE WERE CLBING THROUGH APPROX 11300 FT, THE DEP CTLR CALLED US AND SAID 'MAINTAIN 11000 FT' WITH AN ADMONISHING TONE IN HIS VOICE. I QUICKLY REDUCED PWR AND PUSHED THE NOSE DOWN, AT WHICH TIME OUR ALT HAD PEAKED AT ABOUT 11000 FT. BOTH OF US ARE CERTAIN THAT WE WERE CLRED TO 15000 FT AND BOTH OF US ARE CERTAIN THAT WE DIDN'T GET AN AMENDMENT TO OUR CLRNC. AS WE WERE TRYING TO FIGURE WHAT HAD JUST HAPPENED, THE DEP CTLR HANDED US OFF TO ZHU. I THINK WHAT PROBABLY HAPPENED WAS THAT NEW ORLEANS HAD SPECIAL PROCS IN EFFECT AT THE TIME BECAUSE OF A SPECIAL EVENT. WE WERE PROBABLY CLRED TO 15000 FT IN ERROR AND IT WAS NOT NOTICED UNTIL WE WERE OBVIOUSLY CLBING THROUGH 11000 FT. SUPPLEMENTAL INFO FROM ACN 537370: NO OTHER TFC WAS INVOLVED. NEITHER OF US COULD RECALL THE STANDARD DEP ALT AT MSY. WE WERE LEFT WITH THE IMPRESSION THIS WAS A NON EVENT, BUT YOU NEVER KNOW.

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.