Narrative:

The first 800 ft of runway 6 at rsw were closed due to construction. We knew about this from departure ATIS and NOTAMS. Prior to takeoff, we were cleared to back taxi from taxiway A2 to position and hold, runway 6. I taxied past the temporary runway threshold line far enough to do a 180 degree turn, then back across the line and held. The tower told us that I had used an unauthorized part of the runway for taxi. I thought it was legal to use this area for taxi because it looked like just a displaced threshold to both myself and our first officer. It was marked with ICAO type pre-threshold chevrons but was not barricaded at the temporary threshold line. There was a barricade further west prior to the chevron markings. We took off uneventfully after this.

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Original NASA ASRS Text

Title: CAPT OF AN MLG ACR ACFT TAXIED ON A CLOSED PORTION OF RWY WHEN BACK TAXIING ON RWY FOR TKOF.

Narrative: THE FIRST 800 FT OF RWY 6 AT RSW WERE CLOSED DUE TO CONSTRUCTION. WE KNEW ABOUT THIS FROM DEP ATIS AND NOTAMS. PRIOR TO TKOF, WE WERE CLRED TO BACK TAXI FROM TXWY A2 TO POS AND HOLD, RWY 6. I TAXIED PAST THE TEMPORARY RWY THRESHOLD LINE FAR ENOUGH TO DO A 180 DEG TURN, THEN BACK ACROSS THE LINE AND HELD. THE TWR TOLD US THAT I HAD USED AN UNAUTH PART OF THE RWY FOR TAXI. I THOUGHT IT WAS LEGAL TO USE THIS AREA FOR TAXI BECAUSE IT LOOKED LIKE JUST A DISPLACED THRESHOLD TO BOTH MYSELF AND OUR FO. IT WAS MARKED WITH ICAO TYPE PRE-THRESHOLD CHEVRONS BUT WAS NOT BARRICADED AT THE TEMPORARY THRESHOLD LINE. THERE WAS A BARRICADE FURTHER W PRIOR TO THE CHEVRON MARKINGS. WE TOOK OFF UNEVENTFULLY AFTER THIS.

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.