Narrative:

I had both air carrier XXX and air carrier xyx on my frequency at the time. Air carrier xyx was at FL330 and air carrier XXX was at FL290 about 20 miles in-trail. I issued a clearance to air carrier xyx to cross 20 mi south of eno at FL240. Air carrier XXX read back the clearance but neither myself nor my d-side controller caught the error. Luckily, air carrier xyx called and advised that he thought that air carrier XXX had taken the clearance. Only then did I realize there had been a mistake. I then corrected the clearance of air carrier XXX and reissued the clearance to air carrier xyx, thanking him also for his help. If air carrier XXX had had another aircraft head-on at FL280, the results of this error could have been disastrous. The ironic part of this story is that several months ago, I advised one of our staff persons of these 2 particular call signs. I told him that the 2 flts regularly (as in nearly every night) are on the same frequency numerous times with each other during their flts from florida to newark and that they create much confusion, additional workload, and increased safety hazard each night. Our staff person contacted the airline and was told that probably nothing would be done about it, even in the interest of safety. Apparently, nothing has been done. The situation has been discussed with pilots over the frequency and with supervisors, yet they still fly through each night. Something needs to be done!

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Original NASA ASRS Text

Title: ACFT WITH SIMILAR SOUNDING CALL SIGN ACCEPTED DESCENT CLRNC INTENDED FOR ANOTHER ACFT.

Narrative: I HAD BOTH ACR XXX AND ACR XYX ON MY FREQ AT THE TIME. ACR XYX WAS AT FL330 AND ACR XXX WAS AT FL290 ABOUT 20 MILES IN-TRAIL. I ISSUED A CLRNC TO ACR XYX TO CROSS 20 MI S OF ENO AT FL240. ACR XXX READ BACK THE CLRNC BUT NEITHER MYSELF NOR MY D-SIDE CTLR CAUGHT THE ERROR. LUCKILY, ACR XYX CALLED AND ADVISED THAT HE THOUGHT THAT ACR XXX HAD TAKEN THE CLRNC. ONLY THEN DID I REALIZE THERE HAD BEEN A MISTAKE. I THEN CORRECTED THE CLRNC OF ACR XXX AND REISSUED THE CLRNC TO ACR XYX, THANKING HIM ALSO FOR HIS HELP. IF ACR XXX HAD HAD ANOTHER ACFT HEAD-ON AT FL280, THE RESULTS OF THIS ERROR COULD HAVE BEEN DISASTROUS. THE IRONIC PART OF THIS STORY IS THAT SEVERAL MONTHS AGO, I ADVISED ONE OF OUR STAFF PERSONS OF THESE 2 PARTICULAR CALL SIGNS. I TOLD HIM THAT THE 2 FLTS REGULARLY (AS IN NEARLY EVERY NIGHT) ARE ON THE SAME FREQ NUMEROUS TIMES WITH EACH OTHER DURING THEIR FLTS FROM FLORIDA TO NEWARK AND THAT THEY CREATE MUCH CONFUSION, ADDITIONAL WORKLOAD, AND INCREASED SAFETY HAZARD EACH NIGHT. OUR STAFF PERSON CONTACTED THE AIRLINE AND WAS TOLD THAT PROBABLY NOTHING WOULD BE DONE ABOUT IT, EVEN IN THE INTEREST OF SAFETY. APPARENTLY, NOTHING HAS BEEN DONE. THE SITUATION HAS BEEN DISCUSSED WITH PLTS OVER THE FREQ AND WITH SUPVRS, YET THEY STILL FLY THROUGH EACH NIGHT. SOMETHING NEEDS TO BE DONE!

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.