Narrative:

We received a clearance to taxi into position and hold on runway 25 at las. The first officer confirmed this by reading back the instructions. We held in position for about 2.5 mins and were then cleared for takeoff. The engines had just begun acceleration when takeoff clearance was cancelled. At this point an air carrier jet was told to go around on its approach to 25. Tower then gave us permission to takeoff. We were later told to contact tower at our next stop. They claimed we had taken the runway west/O clearance--not true.

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Original NASA ASRS Text

Title: ACR LGT UNAUTH RWY ENTRY CLAIMED BY ATCT LCL CTLR AT LAS.

Narrative: WE RECEIVED A CLRNC TO TAXI INTO POS AND HOLD ON RWY 25 AT LAS. THE F/O CONFIRMED THIS BY READING BACK THE INSTRUCTIONS. WE HELD IN POS FOR ABOUT 2.5 MINS AND WERE THEN CLRED FOR TKOF. THE ENGS HAD JUST BEGUN ACCELERATION WHEN TKOF CLRNC WAS CANCELLED. AT THIS POINT AN ACR JET WAS TOLD TO GO AROUND ON ITS APCH TO 25. TWR THEN GAVE US PERMISSION TO TKOF. WE WERE LATER TOLD TO CONTACT TWR AT OUR NEXT STOP. THEY CLAIMED WE HAD TAKEN THE RWY W/O CLRNC--NOT TRUE.

Data retrieved from NASA's ASRS site as of August 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.