Narrative:

We were holding short of runway 35L at intersection 31. Several company aircraft were cleared for takeoff, even several that arrived at intersection 32 after us. We sat at 31 quietly for 13 mins. An air carrier Y widebody transport took off and rotated +/-200-400' downfield from us, followed by an large transport. They both rotated so early that I was worried about wake turbulence from them when the tower cleared us into position and hold right. I told tower I was going to swing out a little for wake turbulence. No response, however. We back-taxied slightly beyond intersection 32. An air carrier Y large transport was in the process of taxiing onto runway 35L from the end. Tower came on and said, 'where're you going?' I told tower we were back-taxiing slightly for wake turbulence and asked if he wanted me to get off the runway. 'Yes, get off at 32 and taxi to runway 35R.' we sat at runway 35R for another 10 mins and took off on runway 35R. Later that day I went to our chief pilot's office and discussed this with him. We both agreed that back-taxi is not authority/authorized west/O direct clearance from tower to do so.

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Original NASA ASRS Text

Title: COMMUTER LTT BACK-TAXIED ON RWY AT DFW WITHOUT CLRNC. TWR HAD THE ACFT EXIT THE RWY AND TAXI TO A PARALLEL RWY.

Narrative: WE WERE HOLDING SHORT OF RWY 35L AT INTXN 31. SEVERAL COMPANY ACFT WERE CLRED FOR TKOF, EVEN SEVERAL THAT ARRIVED AT INTXN 32 AFTER US. WE SAT AT 31 QUIETLY FOR 13 MINS. AN ACR Y WDB TOOK OFF AND ROTATED +/-200-400' DOWNFIELD FROM US, FOLLOWED BY AN LGT. THEY BOTH ROTATED SO EARLY THAT I WAS WORRIED ABOUT WAKE TURB FROM THEM WHEN THE TWR CLRED US INTO POS AND HOLD RIGHT. I TOLD TWR I WAS GOING TO SWING OUT A LITTLE FOR WAKE TURB. NO RESPONSE, HOWEVER. WE BACK-TAXIED SLIGHTLY BEYOND INTXN 32. AN ACR Y LGT WAS IN THE PROCESS OF TAXIING ONTO RWY 35L FROM THE END. TWR CAME ON AND SAID, 'WHERE'RE YOU GOING?' I TOLD TWR WE WERE BACK-TAXIING SLIGHTLY FOR WAKE TURB AND ASKED IF HE WANTED ME TO GET OFF THE RWY. 'YES, GET OFF AT 32 AND TAXI TO RWY 35R.' WE SAT AT RWY 35R FOR ANOTHER 10 MINS AND TOOK OFF ON RWY 35R. LATER THAT DAY I WENT TO OUR CHIEF PLT'S OFFICE AND DISCUSSED THIS WITH HIM. WE BOTH AGREED THAT BACK-TAXI IS NOT AUTH W/O DIRECT CLRNC FROM TWR TO DO SO.

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.