Narrative:

We were climbing to FL240. The altitude had been captured and I thought we had leveled off. Just then we were told to cross 30 mi north of a fix at FL200. I thought we were level at FL240, but we were in a slight climb. So when we set FL200 in the FMC panel the aircraft reverted to vertical speed of 600 FPM climb. We had climbed to FL244 when I noticed it and stopped it at FL246. There was no conflict, I don't think the controller ever noticed. In training it was suggested that any time we touch the MCP we point and announce with the flight mode enunciator says. I now do this and do believe if it was policy rather than suggested, it might help keep this from happening to someone else.

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Original NASA ASRS Text

Title: ALT OVERSHOOT BY A319 FLC DURING HIGH ALT DEP CLB.

Narrative: WE WERE CLBING TO FL240. THE ALT HAD BEEN CAPTURED AND I THOUGHT WE HAD LEVELED OFF. JUST THEN WE WERE TOLD TO CROSS 30 MI N OF A FIX AT FL200. I THOUGHT WE WERE LEVEL AT FL240, BUT WE WERE IN A SLIGHT CLB. SO WHEN WE SET FL200 IN THE FMC PANEL THE ACFT REVERTED TO VERT SPD OF 600 FPM CLB. WE HAD CLBED TO FL244 WHEN I NOTICED IT AND STOPPED IT AT FL246. THERE WAS NO CONFLICT, I DON'T THINK THE CTLR EVER NOTICED. IN TRAINING IT WAS SUGGESTED THAT ANY TIME WE TOUCH THE MCP WE POINT AND ANNOUNCE WITH THE FLT MODE ENUNCIATOR SAYS. I NOW DO THIS AND DO BELIEVE IF IT WAS POLICY RATHER THAN SUGGESTED, IT MIGHT HELP KEEP THIS FROM HAPPENING TO SOMEONE ELSE.

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.