Narrative:

Controller gave a crossing restr of 40 mi southeast of ord at 10000 ft MSL. Captain read back 10000 ft and both of us pointed to and confirmed 10000 ft in the altitude alert box. Passing through 10400 ft the controller called and asked us to 'climb back up to 11000 ft.' we climbed to 11000 ft MSL and were then handed off to approach control. I don't even know if this is an incident, however, the words 'climb back up to' made me believe he thought he'd cleared us to 11000 ft instead of 10000 ft. Supplemental information from acn 534940: ZAU cleared us to cross 40 NM south of ord at 10000 ft, which is how I read the clearance back to him.

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Original NASA ASRS Text

Title: A B727 CREW, DSNDING INTO ORD, OVERSHOT ASSIGNED ALT.

Narrative: CTLR GAVE A XING RESTR OF 40 MI SE OF ORD AT 10000 FT MSL. CAPT READ BACK 10000 FT AND BOTH OF US POINTED TO AND CONFIRMED 10000 FT IN THE ALT ALERT BOX. PASSING THROUGH 10400 FT THE CTLR CALLED AND ASKED US TO 'CLB BACK UP TO 11000 FT.' WE CLBED TO 11000 FT MSL AND WERE THEN HANDED OFF TO APCH CTL. I DON'T EVEN KNOW IF THIS IS AN INCIDENT, HOWEVER, THE WORDS 'CLB BACK UP TO' MADE ME BELIEVE HE THOUGHT HE'D CLRED US TO 11000 FT INSTEAD OF 10000 FT. SUPPLEMENTAL INFO FROM ACN 534940: ZAU CLRED US TO CROSS 40 NM S OF ORD AT 10000 FT, WHICH IS HOW I READ THE CLRNC BACK TO HIM.

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.