Narrative:

ATC originally cleared the flight to FL230 then amended clearance to maintain FL210. Passing through FL190, crew reset altitude alerter to new altitude. PF did not hear alert go off because of cockpit noise and overshot altitude by 500 ft then returned to FL210. I believe that he was still thinking about going to FL230. Supplemental information from acn 310190: PF had FL230 still on his mind.

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Original NASA ASRS Text

Title: FA28 FLC RECEIVED AN AMENDED ALT CLRNC BUT CONTINUED TO CLB TO THE LAST ASSIGNED ALT.

Narrative: ATC ORIGINALLY CLRED THE FLT TO FL230 THEN AMENDED CLRNC TO MAINTAIN FL210. PASSING THROUGH FL190, CREW RESET ALT ALERTER TO NEW ALT. PF DID NOT HEAR ALERT GO OFF BECAUSE OF COCKPIT NOISE AND OVERSHOT ALT BY 500 FT THEN RETURNED TO FL210. I BELIEVE THAT HE WAS STILL THINKING ABOUT GOING TO FL230. SUPPLEMENTAL INFO FROM ACN 310190: PF HAD FL230 STILL ON HIS MIND.

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.