Narrative:

We were instructed to level at FL240, the aad went off as we passed through FL230. I then called out 'out of FL230 for FL240.' the PF acknowledged 'roger.' I then continued with my paperwork, and after a few seconds, I glanced up and saw the altimeter at FL242 and the aircraft still climbing. I called the deviation and immediately punched off the autoplt and pitched the aircraft over to correct the altitude. The first officer, PF, had gotten distraction with reprogramming the LORAN. No mention was made about altitude by ATC.

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Original NASA ASRS Text

Title: DC9-41 WAS CLBING TO FL240. 1000 FT TO GO CALL WAS MADE AND PNF LOOKED UP AS THEY WERE CLBING THROUGH FL242.

Narrative: WE WERE INSTRUCTED TO LEVEL AT FL240, THE AAD WENT OFF AS WE PASSED THROUGH FL230. I THEN CALLED OUT 'OUT OF FL230 FOR FL240.' THE PF ACKNOWLEDGED 'ROGER.' I THEN CONTINUED WITH MY PAPERWORK, AND AFTER A FEW SECONDS, I GLANCED UP AND SAW THE ALTIMETER AT FL242 AND THE ACFT STILL CLBING. I CALLED THE DEV AND IMMEDIATELY PUNCHED OFF THE AUTOPLT AND PITCHED THE ACFT OVER TO CORRECT THE ALT. THE FO, PF, HAD GOTTEN DISTR WITH REPROGRAMMING THE LORAN. NO MENTION WAS MADE ABOUT ALT BY ATC.

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.