Narrative:

ZID cleared us to cross 25 southwest of fwa VORTAC at FL290. I heard and read back 25 southwest at FL240. Copilot also understood the center to have said FL240. We changed to ZAU and reported descending to FL240. After leveling off the center called back with surprise in their voice asking our altitude. No conflict was reported. A better 'hearback' from indianapolis could have prevented this error.

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Original NASA ASRS Text

Title: ACR LGT ALT DEVIATION OVERSHOT CROSSING RESTRICTION DURING DESCENT.

Narrative: ZID CLRED US TO CROSS 25 SW OF FWA VORTAC AT FL290. I HEARD AND READ BACK 25 SW AT FL240. COPLT ALSO UNDERSTOOD THE CENTER TO HAVE SAID FL240. WE CHANGED TO ZAU AND REPORTED DESCENDING TO FL240. AFTER LEVELING OFF THE CENTER CALLED BACK WITH SURPRISE IN THEIR VOICE ASKING OUR ALT. NO CONFLICT WAS REPORTED. A BETTER 'HEARBACK' FROM INDIANAPOLIS COULD HAVE PREVENTED THIS ERROR.

Data retrieved from NASA's ASRS site as of August 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.