B737 landing den observed parallel traffic lining up with wrong runway and executes go around.

Attributes
ACN	615943
Time
Date	200405
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : den.airport
State Reference	CO
Altitude	msl single value : 9000
Environment
Weather Elements	Windshear
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : d01.tracon
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 16l other
Flight Phase	descent : approach landing : go around
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : d01.tracon
Operator	common carrier : air carrier
Make Model Name	Airbus Industrie Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 12000 flight time type : 5500
ASRS Report	615943
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 5000 flight time type : 400
ASRS Report	615941
Events
Anomaly	conflict : airborne less severe non adherence : clearance other spatial deviation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : took precautionary avoidance action other
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 0 vertical : 2000
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Operational Deviation Inter Facility Coordination Failure Pilot Deviation

Narrative:

After a go around due to windshear, we were being vectored back to intercept a visual approach runway 16L. Airport was called in sight and we were cleared for visual runway 16L. Traffic was also in sight and cleared for visual runway 16R (air carrier Y). Air carrier Y appeared to be lining up for runway 16L below us. We stayed well left of runway 16L and confirmed traffic was for runway 16R with approach. The first officer confirmed the traffic moving below us and we flew left of runway 16L, discontinued the approach, coordinated with ATC to break off the approach, declared minimum fuel. Subsequent approach to runway 16L was uneventful. We also confirmed proper visual alignment, navaids and courses, as well as proper visual clues. Continuing on the approach would have resulted in definite loss of separation. I called tower and approach after event for them to follow up on conflict. Supplemental information from acn 615941: I looked off the right side of the aircraft and about 2000 ft below us was an A319/320. He appeared to be on the final approach course for runway 16L. We asked approach to verify that the other aircraft was on the runway 16R approach course. We called the tower and they were not aware of any aircraft that landed on the wrong runway. We also called approach and asked the same question. They replied that they would review the tapes. I would bet money that we would have hit them had we continued our approach to runway 16L.

Original NASA ASRS Text

Title: B737 LNDG DEN OBSERVED PARALLEL TFC LINING UP WITH WRONG RWY AND EXECUTES GAR.

Narrative: AFTER A GAR DUE TO WINDSHEAR, WE WERE BEING VECTORED BACK TO INTERCEPT A VISUAL APCH RWY 16L. ARPT WAS CALLED IN SIGHT AND WE WERE CLRED FOR VISUAL RWY 16L. TFC WAS ALSO IN SIGHT AND CLRED FOR VISUAL RWY 16R (ACR Y). ACR Y APPEARED TO BE LINING UP FOR RWY 16L BELOW US. WE STAYED WELL L OF RWY 16L AND CONFIRMED TFC WAS FOR RWY 16R WITH APCH. THE FO CONFIRMED THE TFC MOVING BELOW US AND WE FLEW L OF RWY 16L, DISCONTINUED THE APCH, COORDINATED WITH ATC TO BREAK OFF THE APCH, DECLARED MINIMUM FUEL. SUBSEQUENT APCH TO RWY 16L WAS UNEVENTFUL. WE ALSO CONFIRMED PROPER VISUAL ALIGNMENT, NAVAIDS AND COURSES, AS WELL AS PROPER VISUAL CLUES. CONTINUING ON THE APCH WOULD HAVE RESULTED IN DEFINITE LOSS OF SEPARATION. I CALLED TWR AND APCH AFTER EVENT FOR THEM TO FOLLOW UP ON CONFLICT. SUPPLEMENTAL INFO FROM ACN 615941: I LOOKED OFF THE R SIDE OF THE ACFT AND ABOUT 2000 FT BELOW US WAS AN A319/320. HE APPEARED TO BE ON THE FINAL APCH COURSE FOR RWY 16L. WE ASKED APCH TO VERIFY THAT THE OTHER ACFT WAS ON THE RWY 16R APCH COURSE. WE CALLED THE TWR AND THEY WERE NOT AWARE OF ANY ACFT THAT LANDED ON THE WRONG RWY. WE ALSO CALLED APCH AND ASKED THE SAME QUESTION. THEY REPLIED THAT THEY WOULD REVIEW THE TAPES. I WOULD BET MONEY THAT WE WOULD HAVE HIT THEM HAD WE CONTINUED OUR APCH TO RWY 16L.

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.