Narrative:

We were departing pit from the gate. Ramp instructed us to contact ground. As we made the turn; the captain instructed me to start engine 2. After engine start; I performed a takeoff briefing; as it was my leg. Just as I finished; the flight attendant called up to notify of a secure cabin. I then made the PA asking them to be seated for takeoff. I then contacted ground and was instructed to taxi to 10C. It was a short taxi. As we approached the hold short marks for 10C on taxiway west the captain said something to the effect of 'it says 10C approach' and continued rolling. As soon as I realized he was not going to stop I said; 'stop!' and jumped on the brakes; but by this time about half the aircraft was over the hold short marks. The captain questioned why I did that because the ground markings said '10C appr;' but I pointed out the runway threshold (displaced) and that we were taxiing on to the runway without authorization. I quickly contacted tower; we were instructed to taxi into position and hold short and the flight continued without any disruption or mention of the incident from ATC. The markings were a bit confusing. Because of the displaced threshold the hold short line wasn't officially for the runway so the approach part added confusion. However it was a hold short line; not an ILS critical line.

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Original NASA ASRS Text

Title: Flight crew taxied beyond the Runway 10C hold lines at PIT.

Narrative: We were departing PIT from the gate. Ramp instructed us to contact ground. As we made the turn; the Captain instructed me to start engine 2. After engine start; I performed a takeoff briefing; as it was my leg. Just as I finished; the Flight Attendant called up to notify of a secure cabin. I then made the PA asking them to be seated for takeoff. I then contacted ground and was instructed to taxi to 10C. It was a short taxi. As we approached the hold short marks for 10C on Taxiway W the Captain said something to the effect of 'It says 10C Approach' and continued rolling. As soon as I realized he was not going to stop I said; 'Stop!' and jumped on the brakes; but by this time about half the aircraft was over the hold short marks. The Captain questioned why I did that because the ground markings said '10C APPR;' but I pointed out the runway threshold (displaced) and that we were taxiing on to the runway without authorization. I quickly contacted tower; we were instructed to taxi into position and hold short and the flight continued without any disruption or mention of the incident from ATC. The markings were a bit confusing. Because of the displaced threshold the hold short line wasn't officially for the runway so the approach part added confusion. However it was a hold short line; not an ILS critical line.

Data retrieved from NASA's ASRS site as of April 2012 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.