Narrative:

Flight slc-pdx was in climb on autoplt. Center pointed out traffic 10 O'clock at FL290. I made visual contact and verified altitude capture on VNAV. TCASII resolution advised descend. First officer disengaged autoplt and aircraft ballooned to 28200 ft. First officer returned to FL280 immediately. No further action was required.

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Original NASA ASRS Text

Title: FLC OF AN MLG ACR ACFT OVERSHOT ASSIGNED ALT DURING CLB.

Narrative: FLT SLC-PDX WAS IN CLB ON AUTOPLT. CTR POINTED OUT TFC 10 O'CLOCK AT FL290. I MADE VISUAL CONTACT AND VERIFIED ALT CAPTURE ON VNAV. TCASII RESOLUTION ADVISED DSND. FO DISENGAGED AUTOPLT AND ACFT BALLOONED TO 28200 FT. FO RETURNED TO FL280 IMMEDIATELY. NO FURTHER ACTION WAS REQUIRED.

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.