Narrative:

Aircraft Y; an LJ31; was climbing off of lbb requesting FL410. Air carrier X departed dfw was nwbound at FL340. An internal LOA would have aircraft Y climbing to FL290 entering my sector 47. Initially; the previous sector 93 was going to release control to FL370 via the LOA; and would never talk to the aircraft. ZFW is in the process of consolidating 7 areas to 6 and sector 93 will become part of my area. The sector has been physically moved right next to 47. These are 2 large; frequently busy sectors and it can be hard to hear yourself think when both are busy. A cpc from our area was training on 93 d-side. He saw my traffic at FL340; overrode the LOA; took radar contact on aircraft Y and coordination a climb to FL330 with us. He released control of aircraft Y at 4 mins from confliction; vector lengths indicated aircraft Y would pass 7 mi behind air carrier X. Aircraft Y ground speed was increasing in the climb. I intended to turn aircraft Y 10 degrees right and continue the climb to FL350 (I had other traffic at FL360). Aircraft Y was climbing at 1500 FPM and would top air carrier X before the conflict point. The sector 93 r-side; who is known to not switch aircraft to the next sector until well after his conflicts are resolved (as per 7110.65R) did not switch aircraft Y until the common boundary. I was situationting right next to him and could see he had no traffic for aircraft Y. When aircraft Y came to my frequency; he was leveling at FL330; which meant his ground speed would be increasing and he would probably take another 20-30 seconds to resume his climb. I intended to turn him 15 degrees right now. I had been on position over 1 1/2 hours with steady traffic and words and call signs begin getting transposed. I said 'turn 15 degrees left; climb and maintain FL350.' when I heard the readback; I recognized my mistake and immediately corrected it to a right turn. I got no response so repeated the clearance. I got no response; so I called for aircraft Y with no answer I scanned the rest of my sector and tried again. Aircraft Y responded and I turned him 30 degrees right. Separation was lost 30 seconds later. The loss of communication after the incorrect clearance is critical. Pilots have no accountability for communications in the present system. The FAA's current 'fix on fail' policy for equipment maintenance may be a factor. There are currently at least 2 'dead spots' in other airspace that we consistently lose contact with aircraft around FL200. Aircraft Y may have hit a 'dead spot.'

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Original NASA ASRS Text

Title: ZFW CTLR EXPERIENCED OPERROR AT FL340; INITIALLY ISSUING A WRONG DIRECTION TURN; THEN CORRECTIVE ACTION ISSUED TOO LATE FOR SEPARATION DUE TO COM FAILURE.

Narrative: ACFT Y; AN LJ31; WAS CLBING OFF OF LBB REQUESTING FL410. ACR X DEPARTED DFW WAS NWBOUND AT FL340. AN INTERNAL LOA WOULD HAVE ACFT Y CLBING TO FL290 ENTERING MY SECTOR 47. INITIALLY; THE PREVIOUS SECTOR 93 WAS GOING TO RELEASE CTL TO FL370 VIA THE LOA; AND WOULD NEVER TALK TO THE ACFT. ZFW IS IN THE PROCESS OF CONSOLIDATING 7 AREAS TO 6 AND SECTOR 93 WILL BECOME PART OF MY AREA. THE SECTOR HAS BEEN PHYSICALLY MOVED RIGHT NEXT TO 47. THESE ARE 2 LARGE; FREQUENTLY BUSY SECTORS AND IT CAN BE HARD TO HEAR YOURSELF THINK WHEN BOTH ARE BUSY. A CPC FROM OUR AREA WAS TRAINING ON 93 D-SIDE. HE SAW MY TFC AT FL340; OVERRODE THE LOA; TOOK RADAR CONTACT ON ACFT Y AND COORD A CLB TO FL330 WITH US. HE RELEASED CTL OF ACFT Y AT 4 MINS FROM CONFLICTION; VECTOR LENGTHS INDICATED ACFT Y WOULD PASS 7 MI BEHIND ACR X. ACFT Y GND SPD WAS INCREASING IN THE CLB. I INTENDED TO TURN ACFT Y 10 DEGS R AND CONTINUE THE CLB TO FL350 (I HAD OTHER TFC AT FL360). ACFT Y WAS CLBING AT 1500 FPM AND WOULD TOP ACR X BEFORE THE CONFLICT POINT. THE SECTOR 93 R-SIDE; WHO IS KNOWN TO NOT SWITCH ACFT TO THE NEXT SECTOR UNTIL WELL AFTER HIS CONFLICTS ARE RESOLVED (AS PER 7110.65R) DID NOT SWITCH ACFT Y UNTIL THE COMMON BOUNDARY. I WAS SITUATIONTING RIGHT NEXT TO HIM AND COULD SEE HE HAD NO TFC FOR ACFT Y. WHEN ACFT Y CAME TO MY FREQ; HE WAS LEVELING AT FL330; WHICH MEANT HIS GND SPD WOULD BE INCREASING AND HE WOULD PROBABLY TAKE ANOTHER 20-30 SECONDS TO RESUME HIS CLB. I INTENDED TO TURN HIM 15 DEGS RIGHT NOW. I HAD BEEN ON POS OVER 1 1/2 HRS WITH STEADY TFC AND WORDS AND CALL SIGNS BEGIN GETTING TRANSPOSED. I SAID 'TURN 15 DEGS L; CLB AND MAINTAIN FL350.' WHEN I HEARD THE READBACK; I RECOGNIZED MY MISTAKE AND IMMEDIATELY CORRECTED IT TO A R TURN. I GOT NO RESPONSE SO REPEATED THE CLRNC. I GOT NO RESPONSE; SO I CALLED FOR ACFT Y WITH NO ANSWER I SCANNED THE REST OF MY SECTOR AND TRIED AGAIN. ACFT Y RESPONDED AND I TURNED HIM 30 DEGS R. SEPARATION WAS LOST 30 SECONDS LATER. THE LOSS OF COM AFTER THE INCORRECT CLRNC IS CRITICAL. PLTS HAVE NO ACCOUNTABILITY FOR COMS IN THE PRESENT SYS. THE FAA'S CURRENT 'FIX ON FAIL' POLICY FOR EQUIP MAINT MAY BE A FACTOR. THERE ARE CURRENTLY AT LEAST 2 'DEAD SPOTS' IN OTHER AIRSPACE THAT WE CONSISTENTLY LOSE CONTACT WITH ACFT AROUND FL200. ACFT Y MAY HAVE HIT A 'DEAD SPOT.'

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.