Narrative:

ATC cleared us to 5000 ft then quickly amended to 4000 ft. We didn't catch his change and climbed to 5000 ft. The controller questioned us and told us to descend back down to 4000 ft. I was busy teaching a student in the aircraft and did not hear the amendment. I feel the controller should have clarified my altitude sooner.

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Original NASA ASRS Text

Title: INSTRUCTOR PLT WITH STUDENT ON IFR TRAINING FLT HAS ALTDEV.

Narrative: ATC CLRED US TO 5000 FT THEN QUICKLY AMENDED TO 4000 FT. WE DIDN'T CATCH HIS CHANGE AND CLBED TO 5000 FT. THE CTLR QUESTIONED US AND TOLD US TO DSND BACK DOWN TO 4000 FT. I WAS BUSY TEACHING A STUDENT IN THE ACFT AND DID NOT HEAR THE AMENDMENT. I FEEL THE CTLR SHOULD HAVE CLARIFIED MY ALT SOONER.

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.