Narrative:

We were cleared to taxi to runway 27L by following company aircraft. We followed company to the runway where that aircraft did a 270 degree turn. When we called the tower to ask what was happening they told us that we were given the wrong frequency. We switched over to the new tower frequency and checked in. He asked if we were ready to go. I said 1 min and clicked over to the PA to make the departure announcement. When I came back to COM1, I heard the end of the captain's call saying that we were ready. The controller came back with a taxi into position and hold on runway 27L. I read back the position and hold clearance along with our flight number. We were on the runway for about 30 seconds when the tower controller cleared us for takeoff using the other flight's number. He told us that he would work it out. The thing I remember is that after we went to taxi onto the runway the other company flight that we were nose to nose with never moved. Had they even begun to taxi, we would have thought that 1 of us was mistaken. I believe the controller got the wrong strip and sent us into position. I was about to offer for us to turn off the runway when he cleared us for takeoff. There was no further incident.

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Original NASA ASRS Text

Title: EMB135 CREW HAD A RWY INCURSION AT ORD AFTER THE CREW WAS GIVEN THE WRONG LCL CTLR FREQ, AND THEN TOOK A 'POS AND HOLD' CLRNC INTENDED FOR ANOTHER COMPANY ACFT.

Narrative: WE WERE CLRED TO TAXI TO RWY 27L BY FOLLOWING COMPANY ACFT. WE FOLLOWED COMPANY TO THE RWY WHERE THAT ACFT DID A 270 DEG TURN. WHEN WE CALLED THE TWR TO ASK WHAT WAS HAPPENING THEY TOLD US THAT WE WERE GIVEN THE WRONG FREQ. WE SWITCHED OVER TO THE NEW TWR FREQ AND CHKED IN. HE ASKED IF WE WERE READY TO GO. I SAID 1 MIN AND CLICKED OVER TO THE PA TO MAKE THE DEP ANNOUNCEMENT. WHEN I CAME BACK TO COM1, I HEARD THE END OF THE CAPT'S CALL SAYING THAT WE WERE READY. THE CTLR CAME BACK WITH A TAXI INTO POS AND HOLD ON RWY 27L. I READ BACK THE POS AND HOLD CLRNC ALONG WITH OUR FLT NUMBER. WE WERE ON THE RWY FOR ABOUT 30 SECONDS WHEN THE TWR CTLR CLRED US FOR TKOF USING THE OTHER FLT'S NUMBER. HE TOLD US THAT HE WOULD WORK IT OUT. THE THING I REMEMBER IS THAT AFTER WE WENT TO TAXI ONTO THE RWY THE OTHER COMPANY FLT THAT WE WERE NOSE TO NOSE WITH NEVER MOVED. HAD THEY EVEN BEGUN TO TAXI, WE WOULD HAVE THOUGHT THAT 1 OF US WAS MISTAKEN. I BELIEVE THE CTLR GOT THE WRONG STRIP AND SENT US INTO POS. I WAS ABOUT TO OFFER FOR US TO TURN OFF THE RWY WHEN HE CLRED US FOR TKOF. THERE WAS NO FURTHER INCIDENT.

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.