Narrative:

We were cleared to taxi to runway 23 via txwys H and Q. I taxied onto taxiway Q and near the last left turn at the end of the runway, I began looking for a hold short line. Seeing none, we stopped just prior to the turn. When tower cleared us into position, they asked that in the future if we needed to go past the line to ask them first. Apparently the hold line is about where txwys H and Q meet, not where one would be expecting to see it. Runway surface was also discolored somewhat due to 'salt' de-ice chemicals. Supplemental information from acn 538001: we were given taxi instructions by yyz ground to 'taxi to runway 23 via txwys a and H.' runway 23 has an unusual hold short line that is placed much further back on the taxiway (as opposed to just short of the runway). We were unfamiliar with this. After a learjet landed, yyz tower cleared us into position and hold, advised us of the hold short line and basically told us to be more careful next time. During the taxi, the captain asked me to check some different performance numbers. It was during the time I (the first officer) was looking down at the performance book that we taxied by the hold short line. The situation may not have occurred had both sets of our eyes had been looking outside.

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Original NASA ASRS Text

Title: A CL65 PIC CROSSES OVER THE HOLD SHORT LINE FOR RWY 23 AT CYYZ, ONT.

Narrative: WE WERE CLRED TO TAXI TO RWY 23 VIA TXWYS H AND Q. I TAXIED ONTO TXWY Q AND NEAR THE LAST L TURN AT THE END OF THE RWY, I BEGAN LOOKING FOR A HOLD SHORT LINE. SEEING NONE, WE STOPPED JUST PRIOR TO THE TURN. WHEN TWR CLRED US INTO POS, THEY ASKED THAT IN THE FUTURE IF WE NEEDED TO GO PAST THE LINE TO ASK THEM FIRST. APPARENTLY THE HOLD LINE IS ABOUT WHERE TXWYS H AND Q MEET, NOT WHERE ONE WOULD BE EXPECTING TO SEE IT. RWY SURFACE WAS ALSO DISCOLORED SOMEWHAT DUE TO 'SALT' DE-ICE CHEMICALS. SUPPLEMENTAL INFO FROM ACN 538001: WE WERE GIVEN TAXI INSTRUCTIONS BY YYZ GND TO 'TAXI TO RWY 23 VIA TXWYS A AND H.' RWY 23 HAS AN UNUSUAL HOLD SHORT LINE THAT IS PLACED MUCH FURTHER BACK ON THE TXWY (AS OPPOSED TO JUST SHORT OF THE RWY). WE WERE UNFAMILIAR WITH THIS. AFTER A LEARJET LANDED, YYZ TWR CLRED US INTO POS AND HOLD, ADVISED US OF THE HOLD SHORT LINE AND BASICALLY TOLD US TO BE MORE CAREFUL NEXT TIME. DURING THE TAXI, THE CAPT ASKED ME TO CHK SOME DIFFERENT PERFORMANCE NUMBERS. IT WAS DURING THE TIME I (THE FO) WAS LOOKING DOWN AT THE PERFORMANCE BOOK THAT WE TAXIED BY THE HOLD SHORT LINE. THE SIT MAY NOT HAVE OCCURRED HAD BOTH SETS OF OUR EYES HAD BEEN LOOKING OUTSIDE.

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.