Narrative:

Going south on bravo line from ramp at the south entrance (but I was exiting), ord ground gave 'bravo, alpha 7, tango short of T10.' the first officer got the final weights and was heads down after repeating the above instructions. I turned right because I was between A8 and A9 at the south entrance, then I saw the A7 sign in the distance and inadvertently passed up A8 and had to hurry to beat an aircraft on 'a' facing me to A7 left turn. I guess ord ground leaves it up to the pilot whether A8 or A9 according to the general direction of taxi, but I saw that A7 sign so close and completely forgot the second turn onto B and the first officer said 'sorry for being heads down.' I don't go through ord very much, or lately, and it was night and I am responsible, but a lot of controllers at other airports don't give very complete taxi instructions either. If he would have said '18, B, A7, etc' it may have clued me to turn twice. Supplemental information from acn 502317: the ground controller issued taxi instructions on how to get to runway 32L/T10 for takeoff. The instructions were, 'make a right turn on bravo, that's bravo, left at alpha-seven, tango, 32L-T10.' I looked up, noticed our mistake and replied with an acknowledgement of our mistake. We missed the turn, that's all I can say. I should have waited to go 'heads down' until all turns were negotiated. Captain does not regularly fly into ord, and just forgot to turn. Even though we should have caught the emphasis of the taxi instruction, it was different from normal. Ord usually taxies aircraft clockwise on alpha (also known as the 'inner') and taxies aircraft counterclockwise on bravo (also known as the 'outer'). We are sometimes creatures of habit.

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Original NASA ASRS Text

Title: B757 FLC MISS ORD ASSIGNED TAXI OUT ROUTING AND ARE CHALLENGED BY GND CTLR.

Narrative: GOING S ON BRAVO LINE FROM RAMP AT THE S ENTRANCE (BUT I WAS EXITING), ORD GND GAVE 'BRAVO, ALPHA 7, TANGO SHORT OF T10.' THE FO GOT THE FINAL WTS AND WAS HEADS DOWN AFTER REPEATING THE ABOVE INSTRUCTIONS. I TURNED R BECAUSE I WAS BTWN A8 AND A9 AT THE S ENTRANCE, THEN I SAW THE A7 SIGN IN THE DISTANCE AND INADVERTENTLY PASSED UP A8 AND HAD TO HURRY TO BEAT AN ACFT ON 'A' FACING ME TO A7 L TURN. I GUESS ORD GND LEAVES IT UP TO THE PLT WHETHER A8 OR A9 ACCORDING TO THE GENERAL DIRECTION OF TAXI, BUT I SAW THAT A7 SIGN SO CLOSE AND COMPLETELY FORGOT THE SECOND TURN ONTO B AND THE FO SAID 'SORRY FOR BEING HEADS DOWN.' I DON'T GO THROUGH ORD VERY MUCH, OR LATELY, AND IT WAS NIGHT AND I AM RESPONSIBLE, BUT A LOT OF CTLRS AT OTHER ARPTS DON'T GIVE VERY COMPLETE TAXI INSTRUCTIONS EITHER. IF HE WOULD HAVE SAID '18, B, A7, ETC' IT MAY HAVE CLUED ME TO TURN TWICE. SUPPLEMENTAL INFO FROM ACN 502317: THE GND CTLR ISSUED TAXI INSTRUCTIONS ON HOW TO GET TO RWY 32L/T10 FOR TKOF. THE INSTRUCTIONS WERE, 'MAKE A R TURN ON BRAVO, THAT'S BRAVO, L AT ALPHA-SEVEN, TANGO, 32L-T10.' I LOOKED UP, NOTICED OUR MISTAKE AND REPLIED WITH AN ACKNOWLEDGEMENT OF OUR MISTAKE. WE MISSED THE TURN, THAT'S ALL I CAN SAY. I SHOULD HAVE WAITED TO GO 'HEADS DOWN' UNTIL ALL TURNS WERE NEGOTIATED. CAPT DOES NOT REGULARLY FLY INTO ORD, AND JUST FORGOT TO TURN. EVEN THOUGH WE SHOULD HAVE CAUGHT THE EMPHASIS OF THE TAXI INSTRUCTION, IT WAS DIFFERENT FROM NORMAL. ORD USUALLY TAXIES ACFT CLOCKWISE ON ALPHA (ALSO KNOWN AS THE 'INNER') AND TAXIES ACFT COUNTERCLOCKWISE ON BRAVO (ALSO KNOWN AS THE 'OUTER'). WE ARE SOMETIMES CREATURES OF HABIT.

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.