A DC9 flight crew was given traffic to follow and started to line up with the wrong runway at ord.

Attributes
ACN	438579
Time
Date	199905
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : ord.vor
State Reference	IL
Altitude	msl single value : 4000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 30
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 27r
Route In Use	approach : instrument precision
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 27l
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : multi engine
Experience	flight time last 90 days : 200 flight time total : 12700 flight time type : 3000
ASRS Report	438597
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued advisory
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

While on a right base to runway 27R approach control asked us if we had traffic at 1 O'clock position. We both saw an aircraft in that vicinity and I responded, 'traffic in sight.' we were then cleared for the visual behind that traffic. I commented to the first officer that I thought we were closing on our traffic. At that time approach control said we were south of our final and asked if we had traffic ahead in sight -- we did. We then realized that we were following the wrong aircraft and were lining up on runway 27L. As we corrected back, approach said we were 1.5 mi from the runway 27L traffic.

Original NASA ASRS Text

Title: A DC9 FLC WAS GIVEN TFC TO FOLLOW AND STARTED TO LINE UP WITH THE WRONG RWY AT ORD.

Narrative: WHILE ON A R BASE TO RWY 27R APCH CTL ASKED US IF WE HAD TFC AT 1 O'CLOCK POS. WE BOTH SAW AN ACFT IN THAT VICINITY AND I RESPONDED, 'TFC IN SIGHT.' WE WERE THEN CLRED FOR THE VISUAL BEHIND THAT TFC. I COMMENTED TO THE FO THAT I THOUGHT WE WERE CLOSING ON OUR TFC. AT THAT TIME APCH CTL SAID WE WERE S OF OUR FINAL AND ASKED IF WE HAD TFC AHEAD IN SIGHT -- WE DID. WE THEN REALIZED THAT WE WERE FOLLOWING THE WRONG ACFT AND WERE LINING UP ON RWY 27L. AS WE CORRECTED BACK, APCH SAID WE WERE 1.5 MI FROM THE RWY 27L TFC.

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.