Controller became confused with similar sounding call signs.

Attributes
ACN	128282
Time
Date	198911
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : den
State Reference	CO
Altitude	msl bound lower : 7500 msl bound upper : 7500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : den
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : atp pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 8500 flight time type : 150
ASRS Report	128282
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

The controller directed our aircraft to turn south after being cleared for a 'visual approach to runway 26L behind the assigned aircraft' on approximately 4 mi final. There were several aircraft landing at this time and the directions were not normal in nature, therefore, my non flying pilot requested verification. The controller confirmed the southerly vector, and then requested 1 min later what we were doing. It was obvious the ATC controller confused our flight number with another company aircraft. The other company aircraft even volunteered to 'identify' for verification. The ATC controller said that both company aircraft were confused and then later admitted that both aircraft voices sounded alike. Mixing aircraft flight numbers due to sound alike voices does not seem reasonable. The flight numbers were xooa and xoba.

Original NASA ASRS Text

Title: CTLR BECAME CONFUSED WITH SIMILAR SOUNDING CALL SIGNS.

Narrative: THE CTLR DIRECTED OUR ACFT TO TURN S AFTER BEING CLRED FOR A 'VISUAL APCH TO RWY 26L BEHIND THE ASSIGNED ACFT' ON APPROX 4 MI FINAL. THERE WERE SEVERAL ACFT LNDG AT THIS TIME AND THE DIRECTIONS WERE NOT NORMAL IN NATURE, THEREFORE, MY NON FLYING PLT REQUESTED VERIFICATION. THE CTLR CONFIRMED THE SOUTHERLY VECTOR, AND THEN REQUESTED 1 MIN LATER WHAT WE WERE DOING. IT WAS OBVIOUS THE ATC CTLR CONFUSED OUR FLT NUMBER WITH ANOTHER COMPANY ACFT. THE OTHER COMPANY ACFT EVEN VOLUNTEERED TO 'IDENT' FOR VERIFICATION. THE ATC CTLR SAID THAT BOTH COMPANY ACFT WERE CONFUSED AND THEN LATER ADMITTED THAT BOTH ACFT VOICES SOUNDED ALIKE. MIXING ACFT FLT NUMBERS DUE TO SOUND ALIKE VOICES DOES NOT SEEM REASONABLE. THE FLT NUMBERS WERE XOOA AND XOBA.

Data retrieved from NASA's ASRS site as of August 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.