Narrative:

Shortly after takeoff from toronto on pearson 6 departure from runway 24R, we were cleared to 7000 ft. The departure calls for a turn to 245 degrees at the 3.9 DME fix from the ytp VOR. On climb out, just after turning to the 245 degree heading, departure instructed us to turn left to 220 degrees. I fixated on the new heading momentarily and didn't begin my leveloff until nearly 7000 ft -- simultaneously with the first officer's call that I had passed 7000 ft! I had basically fixated on the heading while hand flying an extremely light B757 that was climbing at close to 6000 FPM. Then I exacerbated the situation by choosing the level off and return to 7000 ft as gently as possible. While I may have succeeded in sparing some passenger the discomfort of an abrupt leveloff, the gentle maneuver I used took us up to 7400 ft, well outside to 300 ft of leeway we may have before alarms start going off. At about the time I began my tardy leveloff and descent back to 7000 ft, we also had a TCASII TA indicating we were starting to get close to another airplane. ATC confirmed this, advising us of the traffic on descent into toronto. We did not close on this traffic enough to generate an RA -- whew!

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Original NASA ASRS Text

Title: CAPT OF A B757 OVERSHOT CLB ALT DURING DEP DUE TO DISTR OF HDG CHANGE. RPTR IMMEDIATELY CORRECTED BACK, BUT SLOWLY FOR PAX COMFORT.

Narrative: SHORTLY AFTER TKOF FROM TORONTO ON PEARSON 6 DEP FROM RWY 24R, WE WERE CLRED TO 7000 FT. THE DEP CALLS FOR A TURN TO 245 DEGS AT THE 3.9 DME FIX FROM THE YTP VOR. ON CLBOUT, JUST AFTER TURNING TO THE 245 DEG HDG, DEP INSTRUCTED US TO TURN L TO 220 DEGS. I FIXATED ON THE NEW HDG MOMENTARILY AND DIDN'T BEGIN MY LEVELOFF UNTIL NEARLY 7000 FT -- SIMULTANEOUSLY WITH THE FO'S CALL THAT I HAD PASSED 7000 FT! I HAD BASICALLY FIXATED ON THE HDG WHILE HAND FLYING AN EXTREMELY LIGHT B757 THAT WAS CLBING AT CLOSE TO 6000 FPM. THEN I EXACERBATED THE SIT BY CHOOSING THE LEVEL OFF AND RETURN TO 7000 FT AS GENTLY AS POSSIBLE. WHILE I MAY HAVE SUCCEEDED IN SPARING SOME PAX THE DISCOMFORT OF AN ABRUPT LEVELOFF, THE GENTLE MANEUVER I USED TOOK US UP TO 7400 FT, WELL OUTSIDE TO 300 FT OF LEEWAY WE MAY HAVE BEFORE ALARMS START GOING OFF. AT ABOUT THE TIME I BEGAN MY TARDY LEVELOFF AND DSCNT BACK TO 7000 FT, WE ALSO HAD A TCASII TA INDICATING WE WERE STARTING TO GET CLOSE TO ANOTHER AIRPLANE. ATC CONFIRMED THIS, ADVISING US OF THE TFC ON DSCNT INTO TORONTO. WE DID NOT CLOSE ON THIS TFC ENOUGH TO GENERATE AN RA -- WHEW!

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.