Narrative:

I was controller in charge and also plugged in as coordinator. Controller a working south radar had worked a flight of 8/fgt out, using the call sign XXX. There destination was a MOA. The problem began when they were returning from the MOA. A flight of 4/fgt called VFR using the call sign XXX. Per our LOA, controller a issued an IFR clearance and vectored the aircraft for the visibility approach. About this time, I plugged in as coordinator. Controller a then noticed center flashing another XXX about 35 southwest of montgomery. (I'll refer to them as #2 flight). Controller a advised XXX who were now 10 mi southeast of mgm about the other flight coming back with the same call sign and told them he would refer to the other flight as XXX flight #2. They said okay. (At this point I feel like controller could of switched the 1ST XXX to the tower and established frequency sep but he did not). Approximately 30 seconds later controller a took the handoff on XXX flight #2 from center. Approximately 30 seconds later he cleared XXX flight #1 for the visibility approach, contact tower. XXX flight #2 must of come up on frequency from center about the time controller a gave this clearance to XXX #1 flight and took it as their own. XXX #2 flight descended out of 11000'. I keyed up tower hot line as coordinator and told them to tell XXX #2 flight to maintain 10000' and contact approach. (XXX #1 flight was still on controller a frequency telling him the other flight took their call). The problem was XXX #2 flight was head on with an small aircraft, IFR at 9000'. By the time tower got XXX #2 flight stopped they were at 8000' in which they returned to controller a's frequency. The small aircraft at 9000' said he never saw them. I was told (did not observe) by another controller it was real close to less than standard separation. The 4-FGT's and the small aircraft pilot did not complain. I talked to the ANG on the phone about the problem of 2 flts using the same call sign. I also brought up the fact that they normally don't get clearance for visibility approach and switched to tower on/before initial contact. In my opinion, the second flight should of questioned this clearance. I also feel like controller a could of done a couple things to prevent this from happening. Clearing the first flight for the approach and switch them to tower before taking the handoff from center. Telling the first flight to use another call sign before the second flight came on frequency. Hit the second flight on 243.0 on guard when they started descending. A supervisor was advised of the above situation before the end of the shift.

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Original NASA ASRS Text

Title: FLT OF 4 FGT TOOK A CLRNC FOR ANOTHER FLT OF 4 FGT AND COME CLOSE TO AN SMA AT 9000'.

Narrative: I WAS CIC AND ALSO PLUGGED IN AS COORDINATOR. CTLR A WORKING S RADAR HAD WORKED A FLT OF 8/FGT OUT, USING THE CALL SIGN XXX. THERE DEST WAS A MOA. THE PROB BEGAN WHEN THEY WERE RETURNING FROM THE MOA. A FLT OF 4/FGT CALLED VFR USING THE CALL SIGN XXX. PER OUR LOA, CTLR A ISSUED AN IFR CLRNC AND VECTORED THE ACFT FOR THE VIS APCH. ABOUT THIS TIME, I PLUGGED IN AS COORDINATOR. CTLR A THEN NOTICED CTR FLASHING ANOTHER XXX ABOUT 35 SW OF MONTGOMERY. (I'LL REFER TO THEM AS #2 FLT). CTLR A ADVISED XXX WHO WERE NOW 10 MI SE OF MGM ABOUT THE OTHER FLT COMING BACK WITH THE SAME CALL SIGN AND TOLD THEM HE WOULD REFER TO THE OTHER FLT AS XXX FLT #2. THEY SAID OKAY. (AT THIS POINT I FEEL LIKE CTLR COULD OF SWITCHED THE 1ST XXX TO THE TWR AND ESTABLISHED FREQ SEP BUT HE DID NOT). APPROX 30 SECS LATER CTLR A TOOK THE HDOF ON XXX FLT #2 FROM CTR. APPROX 30 SECS LATER HE CLRED XXX FLT #1 FOR THE VIS APCH, CONTACT TWR. XXX FLT #2 MUST OF COME UP ON FREQ FROM CTR ABOUT THE TIME CTLR A GAVE THIS CLRNC TO XXX #1 FLT AND TOOK IT AS THEIR OWN. XXX #2 FLT DSNDED OUT OF 11000'. I KEYED UP TWR HOT LINE AS COORDINATOR AND TOLD THEM TO TELL XXX #2 FLT TO MAINTAIN 10000' AND CONTACT APCH. (XXX #1 FLT WAS STILL ON CTLR A FREQ TELLING HIM THE OTHER FLT TOOK THEIR CALL). THE PROB WAS XXX #2 FLT WAS HEAD ON WITH AN SMA, IFR AT 9000'. BY THE TIME TWR GOT XXX #2 FLT STOPPED THEY WERE AT 8000' IN WHICH THEY RETURNED TO CTLR A'S FREQ. THE SMA AT 9000' SAID HE NEVER SAW THEM. I WAS TOLD (DID NOT OBSERVE) BY ANOTHER CTLR IT WAS REAL CLOSE TO LTSS. THE 4-FGT'S AND THE SMA PLT DID NOT COMPLAIN. I TALKED TO THE ANG ON THE PHONE ABOUT THE PROB OF 2 FLTS USING THE SAME CALL SIGN. I ALSO BROUGHT UP THE FACT THAT THEY NORMALLY DON'T GET CLRNC FOR VIS APCH AND SWITCHED TO TWR ON/BEFORE INITIAL CONTACT. IN MY OPINION, THE SECOND FLT SHOULD OF QUESTIONED THIS CLRNC. I ALSO FEEL LIKE CTLR A COULD OF DONE A COUPLE THINGS TO PREVENT THIS FROM HAPPENING. CLRING THE FIRST FLT FOR THE APCH AND SWITCH THEM TO TWR BEFORE TAKING THE HDOF FROM CTR. TELLING THE FIRST FLT TO USE ANOTHER CALL SIGN BEFORE THE SECOND FLT CAME ON FREQ. HIT THE SECOND FLT ON 243.0 ON GUARD WHEN THEY STARTED DSNDING. A SUPVR WAS ADVISED OF THE ABOVE SITUATION BEFORE THE END OF THE SHIFT.

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.