Narrative:

On jan/xx/97 on flight XXX from dtw to bgi, while climbing out of dtw, the first officer was flying and dtw departure control cleared us to 13000 ft. As we passed through 12000 ft departure control told us to contact ZOB and cleared us direct to wings intersection. As I acknowledged, the first officer said we were cleared to FL230, as we went through 13000 ft! I said I did not hear FL230 and I pushed the nose over, but we had gone to 13500 ft. As I pushed the nose over to level at 13000 ft, I called ZOB and reported 13000 ft and they cleared us to FL230 and direct to wings intersection. We proceeded to climb and proceed to wings intersection. Nothing was said!

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Original NASA ASRS Text

Title: B727 ALTDEV ALT OVERSHOT IN CLB. FO, PF, THOUGHT HE HEARD FL230 ASSIGNED AND WENT THROUGH 13000 FT, LAST ASSIGNED ALT.

Narrative: ON JAN/XX/97 ON FLT XXX FROM DTW TO BGI, WHILE CLBING OUT OF DTW, THE FO WAS FLYING AND DTW DEP CTL CLRED US TO 13000 FT. AS WE PASSED THROUGH 12000 FT DEP CTL TOLD US TO CONTACT ZOB AND CLRED US DIRECT TO WINGS INTXN. AS I ACKNOWLEDGED, THE FO SAID WE WERE CLRED TO FL230, AS WE WENT THROUGH 13000 FT! I SAID I DID NOT HEAR FL230 AND I PUSHED THE NOSE OVER, BUT WE HAD GONE TO 13500 FT. AS I PUSHED THE NOSE OVER TO LEVEL AT 13000 FT, I CALLED ZOB AND RPTED 13000 FT AND THEY CLRED US TO FL230 AND DIRECT TO WINGS INTXN. WE PROCEEDED TO CLB AND PROCEED TO WINGS INTXN. NOTHING WAS SAID!

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.