Narrative:

Aircraft involved, a C130 inbound to ecg flying northeast at 15000 ft and a dash 8 departure from ewn to clt. There were other aircraft on frequency that required continuous attention. The following is a brief description of the sequence of events leading up to the loss of separation. I received a handoff from nkt approach on air carrier X with a request for direct flo. Direct flo was approved. Air carrier X reported on frequency climbing to 10000 ft and was cleared to maintain 16000 ft. I take a handoff on military Y who reports on my frequency level 15000 ft. I acknowledge and immediately issue air carrier X amended clearance to maintain 14000 ft. I apparently failed to listen for the read-back and thinking the situation resolved return to separating the traffic at pgv. I had not updated the data-tag on air carrier X because I was going to climb the aircraft after he was clear of military Y I turned my attention to pgv but continued to check on the military Y and air carrier X so that I might continue the air carrier X's climb. I observed air carrier X's altitude readout at 14300 ft and believe the readout to be in error until the next readout of 14500 ft. I issued clearance again to air carrier X to maintain 14000 ft. This time there is an acknowledgement and a visual observation of the traffic by air carrier X. Standard separation was lost. Failure to listen for the read-back and allowing other sits to divert my attention from the read-back were the prime causes of this error. Paying attention to that read-back could have prevented this situation.

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Original NASA ASRS Text

Title: OPERROR.

Narrative: ACFT INVOLVED, A C130 INBOUND TO ECG FLYING NE AT 15000 FT AND A DASH 8 DEP FROM EWN TO CLT. THERE WERE OTHER ACFT ON FREQ THAT REQUIRED CONTINUOUS ATTN. THE FOLLOWING IS A BRIEF DESCRIPTION OF THE SEQUENCE OF EVENTS LEADING UP TO THE LOSS OF SEPARATION. I RECEIVED A HDOF FROM NKT APCH ON ACR X WITH A REQUEST FOR DIRECT FLO. DIRECT FLO WAS APPROVED. ACR X RPTED ON FREQ CLBING TO 10000 FT AND WAS CLRED TO MAINTAIN 16000 FT. I TAKE A HDOF ON MIL Y WHO RPTS ON MY FREQ LEVEL 15000 FT. I ACKNOWLEDGE AND IMMEDIATELY ISSUE ACR X AMENDED CLRNC TO MAINTAIN 14000 FT. I APPARENTLY FAILED TO LISTEN FOR THE READ-BACK AND THINKING THE SIT RESOLVED RETURN TO SEPARATING THE TFC AT PGV. I HAD NOT UPDATED THE DATA-TAG ON ACR X BECAUSE I WAS GOING TO CLB THE ACFT AFTER HE WAS CLR OF MIL Y I TURNED MY ATTN TO PGV BUT CONTINUED TO CHK ON THE MIL Y AND ACR X SO THAT I MIGHT CONTINUE THE ACR X'S CLB. I OBSERVED ACR X'S ALT READOUT AT 14300 FT AND BELIEVE THE READOUT TO BE IN ERROR UNTIL THE NEXT READOUT OF 14500 FT. I ISSUED CLRNC AGAIN TO ACR X TO MAINTAIN 14000 FT. THIS TIME THERE IS AN ACKNOWLEDGEMENT AND A VISUAL OBSERVATION OF THE TFC BY ACR X. STANDARD SEPARATION WAS LOST. FAILURE TO LISTEN FOR THE READ-BACK AND ALLOWING OTHER SITS TO DIVERT MY ATTN FROM THE READ-BACK WERE THE PRIME CAUSES OF THIS ERROR. PAYING ATTN TO THAT READ-BACK COULD HAVE PREVENTED THIS SIT.

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.