Wrong call sign used resulted in conflict.

Attributes
ACN	197290
Time
Date	199112
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	msl bound lower : 4250 msl bound upper : 4500
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : atl
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 4000 flight time type : 700
ASRS Report	197290
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	other anomaly other other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

On approach to 26R we were given 4500 ft and heading 180 degrees. Approaching localizer controller gave air carrier X turn right to 270 degrees and join 26R localizer. Captain read back instructions, then ATC said 'no that was for air carrier Y' (3 digit call sign). I started to turn to join the localizer but when ATC said the instructions were for another aircraft we turned back to 180 degree heading. Captain tried to verify our instructions with ATC but the frequency was too busy. We went through the localizer and the captain was finally able to talk to ATC. We were turning back toward the localizer. Our altitude was 4250 ft and the captain reported the field in sight. ATC asked if we had traffic in sight on approach to 27L. We never saw the traffic. TCASII gave a TA but no RA. The problem was caused by confusion on the controller's part when he apparently used the wrong call sign in his transmissions. The controller was very busy and the frequency was very congested.

Original NASA ASRS Text

Title: WRONG CALL SIGN USED RESULTED IN CONFLICT.

Narrative: ON APCH TO 26R WE WERE GIVEN 4500 FT AND HDG 180 DEGS. APCHING LOC CTLR GAVE ACR X TURN R TO 270 DEGS AND JOIN 26R LOC. CAPT READ BACK INSTRUCTIONS, THEN ATC SAID 'NO THAT WAS FOR ACR Y' (3 DIGIT CALL SIGN). I STARTED TO TURN TO JOIN THE LOC BUT WHEN ATC SAID THE INSTRUCTIONS WERE FOR ANOTHER ACFT WE TURNED BACK TO 180 DEG HDG. CAPT TRIED TO VERIFY OUR INSTRUCTIONS WITH ATC BUT THE FREQ WAS TOO BUSY. WE WENT THROUGH THE LOC AND THE CAPT WAS FINALLY ABLE TO TALK TO ATC. WE WERE TURNING BACK TOWARD THE LOC. OUR ALT WAS 4250 FT AND THE CAPT RPTED THE FIELD IN SIGHT. ATC ASKED IF WE HAD TFC IN SIGHT ON APCH TO 27L. WE NEVER SAW THE TFC. TCASII GAVE A TA BUT NO RA. THE PROBLEM WAS CAUSED BY CONFUSION ON THE CTLR'S PART WHEN HE APPARENTLY USED THE WRONG CALL SIGN IN HIS TRANSMISSIONS. THE CTLR WAS VERY BUSY AND THE FREQ WAS VERY CONGESTED.

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.