Narrative:

I was working sector 78 by myself. I was offline coordinating when aircraft X asked for FL380. When I got back; I asked who had called. Aircraft X again asked for FL380. While working at aircraft Z; I climbed aircraft Z to FL380 and amended aircraft Z's flight plan to FL380. Thinking all along it was aircraft Z I was climbing; Z had a jet south of him; also at FL310 also at mach .79. The speeds of aircraft Z and the jet had been fluctuating at times showing the jet overtaking the aircraft Z. I had been watching this possible conflict when aircraft X asked for FL380. I thought problem solved. By climbing aircraft X; I put him in conflict with aircraft Y (aircraft #2). I caught my error when aircraft X's mode C showed him out of FL366. I reclred aircraft X to maintain FL370 and turned aircraft Y 20 degrees right; but this was too late. Aircraft X advised he had gone through FL370 and was going back to FL370. About this time; conflict alert went off. Although I blame myself; 'if' the air carrier jets did not have similar call signs (for instance air carrier XA10 versus air carrier XB10) I don't think I would have confused the aircraft.

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Original NASA ASRS Text

Title: ZAB CTLR EXPERIENCED OPERROR AT FL375 WHEN ISSUING CLB CLRNC TO WRONG ACFT WITH SIMILAR CALL SIGN AND IN CONFLICT WITH ANOTHER ACFT.

Narrative: I WAS WORKING SECTOR 78 BY MYSELF. I WAS OFFLINE COORDINATING WHEN ACFT X ASKED FOR FL380. WHEN I GOT BACK; I ASKED WHO HAD CALLED. ACFT X AGAIN ASKED FOR FL380. WHILE WORKING AT ACFT Z; I CLBED ACFT Z TO FL380 AND AMENDED ACFT Z'S FLT PLAN TO FL380. THINKING ALL ALONG IT WAS ACFT Z I WAS CLBING; Z HAD A JET S OF HIM; ALSO AT FL310 ALSO AT MACH .79. THE SPDS OF ACFT Z AND THE JET HAD BEEN FLUCTUATING AT TIMES SHOWING THE JET OVERTAKING THE ACFT Z. I HAD BEEN WATCHING THIS POSSIBLE CONFLICT WHEN ACFT X ASKED FOR FL380. I THOUGHT PROB SOLVED. BY CLBING ACFT X; I PUT HIM IN CONFLICT WITH ACFT Y (ACFT #2). I CAUGHT MY ERROR WHEN ACFT X'S MODE C SHOWED HIM OUT OF FL366. I RECLRED ACFT X TO MAINTAIN FL370 AND TURNED ACFT Y 20 DEGS R; BUT THIS WAS TOO LATE. ACFT X ADVISED HE HAD GONE THROUGH FL370 AND WAS GOING BACK TO FL370. ABOUT THIS TIME; CONFLICT ALERT WENT OFF. ALTHOUGH I BLAME MYSELF; 'IF' THE ACR JETS DID NOT HAVE SIMILAR CALL SIGNS (FOR INSTANCE ACR XA10 VERSUS ACR XB10) I DON'T THINK I WOULD HAVE CONFUSED THE ACFT.

Data retrieved from NASA's ASRS site as of January 2009 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.