Narrative:

During climb out, cleared to 10000, #1 and #3 altimeter set to AGL, center set to MSL, normal procedure is to reset #1 and #3 to MSL out of 3000 ft AGL, but they were not. I was leveling at 10000 ft and deviated above 10000 ft by 350 ft while in transition back to 10000 ft. The transition from 10350 to 10000 was smooth to keep from tossing the flight attendants about the cabin. I caught the error when my altimeter read 9400 ft, however, we were already passing 10000 ft on the center altitude and climbing 1500 FPM! There was inbound traffic above and to our left at 11000 ft. The cause of this error was my/our failure to reset out altimeters before level off; a stupid mistake which won't be repeated in the future! Supplemental information from acn 221374. TCASII called 'traffic, traffic.' the traffic was approaching from our left 10-11 O'clock position. Traffic had also been advised by departure control. I noticed the vertical separation showing 08 (800 ft) when we should have had a 10 (1000 ft) separation as we leveled off at 10000 ft MSL. First officer stated he was looking at his altimeter, not the center or 'third altimeter.' we had not as yet reset 'our' altimeter to correspond to the MSL setting of the center altimeter therefore there was a 600 ft difference between 'ours' and the 'third' altimeter.

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Original NASA ASRS Text

Title: AN ACR MLG OVERSHOT HIS ASSIGNED ALT ON CLBOUT. THE CREW HAD FAILED TO CHANGE THEIR ALTIMETERS TO QNH FROM QFE.

Narrative: DURING CLBOUT, CLRED TO 10000, #1 AND #3 ALTIMETER SET TO AGL, CTR SET TO MSL, NORMAL PROC IS TO RESET #1 AND #3 TO MSL OUT OF 3000 FT AGL, BUT THEY WERE NOT. I WAS LEVELING AT 10000 FT AND DEVIATED ABOVE 10000 FT BY 350 FT WHILE IN TRANSITION BACK TO 10000 FT. THE TRANSITION FROM 10350 TO 10000 WAS SMOOTH TO KEEP FROM TOSSING THE FLT ATTENDANTS ABOUT THE CABIN. I CAUGHT THE ERROR WHEN MY ALTIMETER READ 9400 FT, HOWEVER, WE WERE ALREADY PASSING 10000 FT ON THE CTR ALT AND CLBING 1500 FPM! THERE WAS INBOUND TFC ABOVE AND TO OUR L AT 11000 FT. THE CAUSE OF THIS ERROR WAS MY/OUR FAILURE TO RESET OUT ALTIMETERS BEFORE LEVEL OFF; A STUPID MISTAKE WHICH WON'T BE REPEATED IN THE FUTURE! SUPPLEMENTAL INFO FROM ACN 221374. TCASII CALLED 'TFC, TFC.' THE TFC WAS APCHING FROM OUR L 10-11 O'CLOCK POS. TFC HAD ALSO BEEN ADVISED BY DEP CTL. I NOTICED THE VERT SEPARATION SHOWING 08 (800 FT) WHEN WE SHOULD HAVE HAD A 10 (1000 FT) SEPARATION AS WE LEVELED OFF AT 10000 FT MSL. FO STATED HE WAS LOOKING AT HIS ALTIMETER, NOT THE CTR OR 'THIRD ALTIMETER.' WE HAD NOT AS YET RESET 'OUR' ALTIMETER TO CORRESPOND TO THE MSL SETTING OF THE CTR ALTIMETER THEREFORE THERE WAS A 600 FT DIFFERENCE BTWN 'OURS' AND THE 'THIRD' ALTIMETER.

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.