Narrative:

We called for taxi out of the gate at ord and were given a, A6, J for runway 9L. When on 'J' we noticed all other aircraft were going to runway 4L via j-w. O'hare was also landing runway 9L and the ATIS called runway 4L not runway 9L for departure, however, we were cleared to runway 9L. This should have been questioned by us but we didn't. We were then cleared into position and hold runway 9L and acknowledged this clearance. Once onto the runway the controller asked who was on runway 9L. We acknowledge and verified our call sign. He told us to continue across the runway, do a 180 degree turn and hold short of runway 9L again. There wound up being traffic on a 2 mi final. He then had us taxi in line with the runway 4L traffic and we departed uneventfully. I feel all along the tower thought they cleared us to runway 4L, but we were issued runway 9L and even cleared into position on runway 9L. Fortunately the error was caught uneventfully. Had we queried the tower initially on runway 4L versus runway 9L this confusion may have been caught sooner.

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Original NASA ASRS Text

Title: FLC OF AN MLG WERE GIVEN TAXI INSTRUCTIONS TO RWY FOR TKOF, INCLUDING IN POS AND HOLD, AND THEN SUBSEQUENTLY, ATC INSTRUCTED THEM TO TAXI OFF THE RWY AND WERE PLACED IN POS FOR TKOF ON THE DEP RWY.

Narrative: WE CALLED FOR TAXI OUT OF THE GATE AT ORD AND WERE GIVEN A, A6, J FOR RWY 9L. WHEN ON 'J' WE NOTICED ALL OTHER ACFT WERE GOING TO RWY 4L VIA J-W. O'HARE WAS ALSO LNDG RWY 9L AND THE ATIS CALLED RWY 4L NOT RWY 9L FOR DEP, HOWEVER, WE WERE CLRED TO RWY 9L. THIS SHOULD HAVE BEEN QUESTIONED BY US BUT WE DIDN'T. WE WERE THEN CLRED INTO POS AND HOLD RWY 9L AND ACKNOWLEDGED THIS CLRNC. ONCE ONTO THE RWY THE CTLR ASKED WHO WAS ON RWY 9L. WE ACKNOWLEDGE AND VERIFIED OUR CALL SIGN. HE TOLD US TO CONTINUE ACROSS THE RWY, DO A 180 DEG TURN AND HOLD SHORT OF RWY 9L AGAIN. THERE WOUND UP BEING TFC ON A 2 MI FINAL. HE THEN HAD US TAXI IN LINE WITH THE RWY 4L TFC AND WE DEPARTED UNEVENTFULLY. I FEEL ALL ALONG THE TWR THOUGHT THEY CLRED US TO RWY 4L, BUT WE WERE ISSUED RWY 9L AND EVEN CLRED INTO POS ON RWY 9L. FORTUNATELY THE ERROR WAS CAUGHT UNEVENTFULLY. HAD WE QUERIED THE TWR INITIALLY ON RWY 4L VERSUS RWY 9L THIS CONFUSION MAY HAVE BEEN CAUGHT SOONER.

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.