Air carrier flight crew gets confused by taxiway signage and taxis on the wrong taxiway.

Attributes
ACN	167030
Time
Date	199012
Day	Sat
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : phl
State Reference	PA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 8000 flight time type : 2500
ASRS Report	167030
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation
Situations
Airport	other physical facility

Narrative:

Once we cleared the end of runway 09R, we were told to taxi via taxiway west. With the visibility down to RVR 1200', we could not see much beyond the yellow taxi line and some signs close to the taxi route. We saw a sign that said taxiway 2 to the 1/2 right, and we followed that yellow taxiway. There was also an air carrier widebody transport parked in front of us, slightly to the left. Once we had made the right turn, I finished the after landing checklist, went off frequency and told company we were on the ground, etc. When I finally looked up, we came to a taxi intersection that said left D straight ahead runway 35. It was at this time we realized we had turned more than just 1/2 right for taxiway west, but actually had turned onto taxiway aa. This was confirmed by looking at the compass heading. There never was any sign with taxiway aa that we could see. Though this was not a safety problem in the sense that no runway incursions occurred. The way the taxi signs are placed can be quite misleading. It seems like with a little extra paint, next to yellow taxi line intxns the taxiway identify could be better labeled.

Original NASA ASRS Text

Title: ACR FLT CREW GETS CONFUSED BY TXWY SIGNAGE AND TAXIS ON THE WRONG TXWY.

Narrative: ONCE WE CLRED THE END OF RWY 09R, WE WERE TOLD TO TAXI VIA TXWY W. WITH THE VISIBILITY DOWN TO RVR 1200', WE COULD NOT SEE MUCH BEYOND THE YELLOW TAXI LINE AND SOME SIGNS CLOSE TO THE TAXI RTE. WE SAW A SIGN THAT SAID TXWY 2 TO THE 1/2 RIGHT, AND WE FOLLOWED THAT YELLOW TXWY. THERE WAS ALSO AN ACR WDB PARKED IN FRONT OF US, SLIGHTLY TO THE LEFT. ONCE WE HAD MADE THE RIGHT TURN, I FINISHED THE AFTER LNDG CHKLIST, WENT OFF FREQ AND TOLD COMPANY WE WERE ON THE GND, ETC. WHEN I FINALLY LOOKED UP, WE CAME TO A TAXI INTXN THAT SAID LEFT D STRAIGHT AHEAD RWY 35. IT WAS AT THIS TIME WE REALIZED WE HAD TURNED MORE THAN JUST 1/2 RIGHT FOR TXWY W, BUT ACTUALLY HAD TURNED ONTO TXWY AA. THIS WAS CONFIRMED BY LOOKING AT THE COMPASS HDG. THERE NEVER WAS ANY SIGN WITH TXWY AA THAT WE COULD SEE. THOUGH THIS WAS NOT A SAFETY PROB IN THE SENSE THAT NO RWY INCURSIONS OCCURRED. THE WAY THE TAXI SIGNS ARE PLACED CAN BE QUITE MISLEADING. IT SEEMS LIKE WITH A LITTLE EXTRA PAINT, NEXT TO YELLOW TAXI LINE INTXNS THE TXWY IDENT COULD BE BETTER LABELED.

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.