A B737-300 flight crew taxies the wrong route en route to departure runway at ord, il.

Attributes
ACN	486180
Time
Date	200009
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ord.airport
State Reference	FL
Altitude	agl single value : 0
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : atp pilot : cfi pilot : commercial pilot : multi engine
Experience	flight time last 90 days : 300 flight time total : 5000 flight time type : 300
ASRS Report	486180
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	incursion : taxiway non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance other
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance Airport Company
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Our flight was cleared from our gate at ord to runway 32L at T-10 intersection via txwys B, M2, M, T. As soon as our clearance to taxi was issued, the ground controller immediately began issuing clrncs to other aircraft. I was unable to read back the clearance route to runway 32L at T-10. The captain taxied the airplane to exit the ramp. I repeated the taxi route to him, and then I began to perform my normal before takeoff checks. During this time I was 'heads down.' our flight also had the additional problem of being at a weight which required us to contact dispatch. I was trying to contact dispatch via ACARS, then by VHF communication. I looked up to see where we were. The captain had turned onto taxiway T from taxiway A7, as opposed to taxiway B. I immediately advised the captain that we had taken a wrong turn. The captain immediately stopped and we contacted ground control to advise them of our mistake. Ground issued new taxi instructions for us and we continued to runway 32L at T-10 via taxiway T. I believe this error was caused by multiple factors, including: frequency congestion, inability to read back a clearance, being assigned a taxi routing that was other than the expected routing, having a short-taxi to the runway, which necessitated me to be 'heads down' soon after we received our taxi clearance, and having to continue to be 'heads down' while I tried to get in touch with company dispatch. This problem could have been avoided by ensuring the captain (25+ yrs experience) understood the taxi route, as opposed to assuming he knew it due to his vast experience at ord.

Original NASA ASRS Text

Title: A B737-300 FLC TAXIES THE WRONG RTE ENRTE TO DEP RWY AT ORD, IL.

Narrative: OUR FLT WAS CLRED FROM OUR GATE AT ORD TO RWY 32L AT T-10 INTXN VIA TXWYS B, M2, M, T. AS SOON AS OUR CLRNC TO TAXI WAS ISSUED, THE GND CTLR IMMEDIATELY BEGAN ISSUING CLRNCS TO OTHER ACFT. I WAS UNABLE TO READ BACK THE CLRNC RTE TO RWY 32L AT T-10. THE CAPT TAXIED THE AIRPLANE TO EXIT THE RAMP. I REPEATED THE TAXI RTE TO HIM, AND THEN I BEGAN TO PERFORM MY NORMAL BEFORE TKOF CHKS. DURING THIS TIME I WAS 'HEADS DOWN.' OUR FLT ALSO HAD THE ADDITIONAL PROB OF BEING AT A WT WHICH REQUIRED US TO CONTACT DISPATCH. I WAS TRYING TO CONTACT DISPATCH VIA ACARS, THEN BY VHF COM. I LOOKED UP TO SEE WHERE WE WERE. THE CAPT HAD TURNED ONTO TXWY T FROM TXWY A7, AS OPPOSED TO TXWY B. I IMMEDIATELY ADVISED THE CAPT THAT WE HAD TAKEN A WRONG TURN. THE CAPT IMMEDIATELY STOPPED AND WE CONTACTED GND CTL TO ADVISE THEM OF OUR MISTAKE. GND ISSUED NEW TAXI INSTRUCTIONS FOR US AND WE CONTINUED TO RWY 32L AT T-10 VIA TXWY T. I BELIEVE THIS ERROR WAS CAUSED BY MULTIPLE FACTORS, INCLUDING: FREQ CONGESTION, INABILITY TO READ BACK A CLRNC, BEING ASSIGNED A TAXI ROUTING THAT WAS OTHER THAN THE EXPECTED ROUTING, HAVING A SHORT-TAXI TO THE RWY, WHICH NECESSITATED ME TO BE 'HEADS DOWN' SOON AFTER WE RECEIVED OUR TAXI CLRNC, AND HAVING TO CONTINUE TO BE 'HEADS DOWN' WHILE I TRIED TO GET IN TOUCH WITH COMPANY DISPATCH. THIS PROB COULD HAVE BEEN AVOIDED BY ENSURING THE CAPT (25+ YRS EXPERIENCE) UNDERSTOOD THE TAXI RTE, AS OPPOSED TO ASSUMING HE KNEW IT DUE TO HIS VAST EXPERIENCE AT ORD.

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.