Narrative:

While taxiing for takeoff on tpa runway 36L, I was concerned about a thunderstorm which had just passed over the field and was now north of the airport. The field was very wet with standing water from the recent shower, and I attempted to position the aircraft while in the holding pad so that the radar would be able to paint our departure route as I held short of the runway. I passed what I thought was a CAT III hold line approaching the runway, but as I came to a stop nearer the runway, there was no other hold short line. At no time did we intrude on the actual runway or pass any runway edge lights or runway edge markings, but it is possible we were beyond the hold short line. Tower made no mention of our position, and when cleared for takeoff, we taxied onto the runway and departed normally. If the hold short line I believed was a CAT III hold line was in fact the normal hold short line, it appeared to be farther from the runway than I was expecting, but the wet txwys and darkness at the end of the runway made it difficult to see in any case. Supplemental information from acn 620831: the captain later told me that due to the lack of visual clues he mistook a seam in the concrete to be the hold short line. I also failed to notice because of heads down duties prior to takeoff.

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Original NASA ASRS Text

Title: AN MD80 FLT CREW CROSSES THE HOLD SHORT LINE FOR RWY 36L AT TPA, FL.

Narrative: WHILE TAXIING FOR TKOF ON TPA RWY 36L, I WAS CONCERNED ABOUT A TSTM WHICH HAD JUST PASSED OVER THE FIELD AND WAS NOW N OF THE ARPT. THE FIELD WAS VERY WET WITH STANDING WATER FROM THE RECENT SHOWER, AND I ATTEMPTED TO POS THE ACFT WHILE IN THE HOLDING PAD SO THAT THE RADAR WOULD BE ABLE TO PAINT OUR DEP RTE AS I HELD SHORT OF THE RWY. I PASSED WHAT I THOUGHT WAS A CAT III HOLD LINE APCHING THE RWY, BUT AS I CAME TO A STOP NEARER THE RWY, THERE WAS NO OTHER HOLD SHORT LINE. AT NO TIME DID WE INTRUDE ON THE ACTUAL RWY OR PASS ANY RWY EDGE LIGHTS OR RWY EDGE MARKINGS, BUT IT IS POSSIBLE WE WERE BEYOND THE HOLD SHORT LINE. TWR MADE NO MENTION OF OUR POS, AND WHEN CLRED FOR TKOF, WE TAXIED ONTO THE RWY AND DEPARTED NORMALLY. IF THE HOLD SHORT LINE I BELIEVED WAS A CAT III HOLD LINE WAS IN FACT THE NORMAL HOLD SHORT LINE, IT APPEARED TO BE FARTHER FROM THE RWY THAN I WAS EXPECTING, BUT THE WET TXWYS AND DARKNESS AT THE END OF THE RWY MADE IT DIFFICULT TO SEE IN ANY CASE. SUPPLEMENTAL INFO FROM ACN 620831: THE CAPT LATER TOLD ME THAT DUE TO THE LACK OF VISUAL CLUES HE MISTOOK A SEAM IN THE CONCRETE TO BE THE HOLD SHORT LINE. I ALSO FAILED TO NOTICE BECAUSE OF HEADS DOWN DUTIES PRIOR TO TKOF.

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.