Narrative:

We taxied out from the FBO via our issued ATC clearance. The clearance was taxi to runway 33 via a taxiway and cross runway 25. As we taxied across runway 25 I saw a sign that said approach for runway 33 and I believed that I saw hold short lines. At this point I told my PIC that he was approaching the hold short lines for runway 33; the PIC replied that those where not hold short lines. A few seconds later the PIC stopped the airplane because he started having doubts as to if we had crossed the hold short lines. As we discussed the issue the tower cleared us for take off. We never saw any other hold short lines as we taxied onto the runway. If you review the airport diagram its difficult to see if there are any hold short lines from the point that we taxied onto the runway. At this point we are not sure if we crossed the hold short line. Next time I will be more aggressive in regards to stopping the airplane.

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Original NASA ASRS Text

Title: G200 First Officer questions whether the hold short line for Runway 33 has been crossed as the crew taxi's to that runway via Taxiway A at DET.

Narrative: We taxied out from the FBO via our issued ATC clearance. The clearance was taxi to Runway 33 via A Taxiway and cross Runway 25. As we taxied across Runway 25 I saw a sign that said approach for Runway 33 and I believed that I saw hold short lines. At this point I told my PIC that he was approaching the hold short lines for Runway 33; the PIC replied that those where not hold short lines. A few seconds later the PIC stopped the airplane because he started having doubts as to if we had crossed the hold short lines. As we discussed the issue the Tower cleared us for take off. We never saw any other hold short lines as we taxied onto the runway. If you review the airport diagram its difficult to see if there are any hold short lines from the point that we taxied onto the runway. At this point we are not sure if we crossed the hold short line. Next time I will be more aggressive in regards to stopping the airplane.

Data retrieved from NASA's ASRS site as of July 2013 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.