Narrative:

I was taxiing to runway 21L at yum. I was told by ground control to hold short of runway 21L. Halfway out during taxi (point a) I was told to hold short of the extended centerline for runway 21R. Instead of looking to the right for runway 21R, I taxied and looked for hold short bars. I wasn't looking for an imaginary line extending from a runway (21R) (that was hundreds of yards away). There were no hold short bars marked because you don't actually cross runway 21R during taxi. I noticed an air carrier plane fly over me (within 450 ft) approaching runway 21R. The controller, at the last min, saw me crossing the extended centerline of runway 21R and told me to cross without delay for the approaching air carrier. The situation could have been solved if the controller told me to hold my position, instead of relying on me to find an imaginary centerline extending from runway 21R. Also, no markings on the ground indicated that I was taxiing in close proximity of the threshold of runway 21R. I needed to rely less on runway markings (hold short lines) and more on always knowing my position while taxiing.

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Original NASA ASRS Text

Title: PLTDEV WHEN RPTR CROSSED THE APCH AREA OF THE EXTENDED RWY AREA DURING THE TIME OF APCH.

Narrative: I WAS TAXIING TO RWY 21L AT YUM. I WAS TOLD BY GND CTL TO HOLD SHORT OF RWY 21L. HALFWAY OUT DURING TAXI (POINT A) I WAS TOLD TO HOLD SHORT OF THE EXTENDED CTRLINE FOR RWY 21R. INSTEAD OF LOOKING TO THE R FOR RWY 21R, I TAXIED AND LOOKED FOR HOLD SHORT BARS. I WASN'T LOOKING FOR AN IMAGINARY LINE EXTENDING FROM A RWY (21R) (THAT WAS HUNDREDS OF YARDS AWAY). THERE WERE NO HOLD SHORT BARS MARKED BECAUSE YOU DON'T ACTUALLY CROSS RWY 21R DURING TAXI. I NOTICED AN ACR PLANE FLY OVER ME (WITHIN 450 FT) APCHING RWY 21R. THE CTLR, AT THE LAST MIN, SAW ME XING THE EXTENDED CTRLINE OF RWY 21R AND TOLD ME TO CROSS WITHOUT DELAY FOR THE APCHING ACR. THE SIT COULD HAVE BEEN SOLVED IF THE CTLR TOLD ME TO HOLD MY POS, INSTEAD OF RELYING ON ME TO FIND AN IMAGINARY CTRLINE EXTENDING FROM RWY 21R. ALSO, NO MARKINGS ON THE GND INDICATED THAT I WAS TAXIING IN CLOSE PROX OF THE THRESHOLD OF RWY 21R. I NEEDED TO RELY LESS ON RWY MARKINGS (HOLD SHORT LINES) AND MORE ON ALWAYS KNOWING MY POS WHILE TAXIING.

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.