Narrative:

Cleared by dulles ground from position short of taxiway Z on taxiway east from south ramp to taxi to runway 30 via taxiway Z/Q. Upon reaching the secondary deicing site on taxiway Z, continued to runway 30 via taxiway on left side. Ground control queried what aircraft was taxiing left on Y9 to runway 30. Replied that we were, air carrier xyz. (Our destination was mex.) ground informed us that we were not on taxiway Q and Y9 was notamed on ATIS not for aircraft with greater than 97 ft wing span. Our A320 wing span is 110 ft. We continued to end of runway and was cleared for takeoff shortly later. As we were approaching the deicing area, a B757 was on the taxiway to the right which is taxiway Z and was waiting for final weights. A turboprop taxied to pass to the left to get around the B757. We followed that direction also as the iad airport diagram appears to show the left side as taxiway Q. The small section that is actually Y9 is not clearly delineated. After entering the runway 30 position and holding, the Y9 designation on the taxiway could be seen much better. Normal ground clrncs at iad for runway 30 is either via taxiway Y to runway 30 or taxiway Z to runway 30 and traffic flows to the left with no direction from ground to do so. Also, clarifying the airport diagram would help greatly.

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Original NASA ASRS Text

Title: AN A320 CREW TAXIES THE WRONG WAY ON THE WAY TO RWY 30 AT IAD. THE PIC FOLLOWED A TURBOPROP AND WENT ONTO A TXWY OTHER THAN CLRED.

Narrative: CLRED BY DULLES GND FROM POS SHORT OF TXWY Z ON TXWY E FROM S RAMP TO TAXI TO RWY 30 VIA TXWY Z/Q. UPON REACHING THE SECONDARY DEICING SITE ON TXWY Z, CONTINUED TO RWY 30 VIA TXWY ON L SIDE. GND CTL QUERIED WHAT ACFT WAS TAXIING L ON Y9 TO RWY 30. REPLIED THAT WE WERE, ACR XYZ. (OUR DEST WAS MEX.) GND INFORMED US THAT WE WERE NOT ON TXWY Q AND Y9 WAS NOTAMED ON ATIS NOT FOR ACFT WITH GREATER THAN 97 FT WING SPAN. OUR A320 WING SPAN IS 110 FT. WE CONTINUED TO END OF RWY AND WAS CLRED FOR TKOF SHORTLY LATER. AS WE WERE APCHING THE DEICING AREA, A B757 WAS ON THE TXWY TO THE R WHICH IS TXWY Z AND WAS WAITING FOR FINAL WTS. A TURBOPROP TAXIED TO PASS TO THE L TO GET AROUND THE B757. WE FOLLOWED THAT DIRECTION ALSO AS THE IAD ARPT DIAGRAM APPEARS TO SHOW THE L SIDE AS TXWY Q. THE SMALL SECTION THAT IS ACTUALLY Y9 IS NOT CLEARLY DELINEATED. AFTER ENTERING THE RWY 30 POS AND HOLDING, THE Y9 DESIGNATION ON THE TXWY COULD BE SEEN MUCH BETTER. NORMAL GND CLRNCS AT IAD FOR RWY 30 IS EITHER VIA TXWY Y TO RWY 30 OR TXWY Z TO RWY 30 AND TFC FLOWS TO THE L WITH NO DIRECTION FROM GND TO DO SO. ALSO, CLARIFYING THE ARPT DIAGRAM WOULD HELP GREATLY.

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.