Narrative:

Captain was flying, I was working the radios. Another company flight, approximately 10 NM ahead of us, was also on frequency. We were at 8000 ft, heading 180 degrees, approximately 15 NM northeast of mia when final controller cleared us to 'turn right 250 degrees, maintain at or above 3000 ft until (waypoint unknown), cleared for the ILS runway 27R.' I read back the entire clearance including my full call sign. Approximately 30 seconds later, while passing approximately 6000 ft, the controller asked us, in an obviously distressed voice, what our altitude was and what were we doing. I told him and then he and another controller told us to level off at 4000 ft. The original controller told us the approach clearance had been for our other company flight. However, our other company flight, who was still on frequency, confirmed that he had not received, nor read back, any approach clearance. Approximately 1 min later, while being vectored behind traffic for a visual to runway 27R, the controller all but admitted to his mistake and apologized. I have decided to pursue it through my company channels, pilot group, and the FAA. I've seen myself and plenty of others make mistakes. However, the potential for disaster in this incident (major airport, lots of traffic) was high.

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Original NASA ASRS Text

Title: ACR B737 ACKNOWLEDGES APCH CLRNC. ZMA CTLR INTERVENES DISPUTING CLRNC, BUT LATER ADMITS WRONG ACFT WAS CLRED FOR APCH.

Narrative: CAPT WAS FLYING, I WAS WORKING THE RADIOS. ANOTHER COMPANY FLT, APPROX 10 NM AHEAD OF US, WAS ALSO ON FREQ. WE WERE AT 8000 FT, HDG 180 DEGS, APPROX 15 NM NE OF MIA WHEN FINAL CTLR CLRED US TO 'TURN R 250 DEGS, MAINTAIN AT OR ABOVE 3000 FT UNTIL (WAYPOINT UNKNOWN), CLRED FOR THE ILS RWY 27R.' I READ BACK THE ENTIRE CLRNC INCLUDING MY FULL CALL SIGN. APPROX 30 SECONDS LATER, WHILE PASSING APPROX 6000 FT, THE CTLR ASKED US, IN AN OBVIOUSLY DISTRESSED VOICE, WHAT OUR ALT WAS AND WHAT WERE WE DOING. I TOLD HIM AND THEN HE AND ANOTHER CTLR TOLD US TO LEVEL OFF AT 4000 FT. THE ORIGINAL CTLR TOLD US THE APCH CLRNC HAD BEEN FOR OUR OTHER COMPANY FLT. HOWEVER, OUR OTHER COMPANY FLT, WHO WAS STILL ON FREQ, CONFIRMED THAT HE HAD NOT RECEIVED, NOR READ BACK, ANY APCH CLRNC. APPROX 1 MIN LATER, WHILE BEING VECTORED BEHIND TFC FOR A VISUAL TO RWY 27R, THE CTLR ALL BUT ADMITTED TO HIS MISTAKE AND APOLOGIZED. I HAVE DECIDED TO PURSUE IT THROUGH MY COMPANY CHANNELS, PLT GROUP, AND THE FAA. I'VE SEEN MYSELF AND PLENTY OF OTHERS MAKE MISTAKES. HOWEVER, THE POTENTIAL FOR DISASTER IN THIS INCIDENT (MAJOR ARPT, LOTS OF TFC) WAS HIGH.

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.