Narrative:

Air carrier X called on at XA40 out of FL350 climbing to FL370 eastbound. Air carrier X's expected rate of climb diminished at a critical time for sep. At XB15 I turned air carrier X 20 degrees left and asked him if he could be leveled in 1 min, at XB24. He said yes. At XB31 I turned air carrier Y 15 degrees left. At XB48 I called the traffic to air carrier X off his wing 6 mi, report reaching FL370. Air carrier X said at that time that he will not be able to be leveled that soon. I turned air carrier Y to a 270 degree heading. Air carrier X called that traffic in sight at 4 O'clock. Sep was lost with 1100' vertical sep and 3.125 mi latitude. C/a activated at XA15. Aedp was set off at XC09. There were 4 sectors active out of 7. There were 8 controllers and 1 supervisor (giving 1 of the controllers a check ride at the positions and 9 controllers on break). Of the previous 9, 5 were fpl's, 2 full manual controllers and 2 manual controller trnees. There were 13 fdb on the pvd, 8 aircraft on frequency (2 on radar vectors, 3 climbing and 0 descending), 3 aircraft off frequency and 2 new data blocks. Overall, in my judgement, an erroneous judgement I might add, I had about 4 mins before X would be a factor with Y. He (X) had only 2000' to go before vertical sep would exist. I had to take care of other traffic situations and did not get back to this situation on time to accomplish sep.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 ACR. OPERATIONAL ERROR.

Narrative: ACR X CALLED ON AT XA40 OUT OF FL350 CLBING TO FL370 EBND. ACR X'S EXPECTED RATE OF CLB DIMINISHED AT A CRITICAL TIME FOR SEP. AT XB15 I TURNED ACR X 20 DEGS LEFT AND ASKED HIM IF HE COULD BE LEVELED IN 1 MIN, AT XB24. HE SAID YES. AT XB31 I TURNED ACR Y 15 DEGS LEFT. AT XB48 I CALLED THE TFC TO ACR X OFF HIS WING 6 MI, RPT REACHING FL370. ACR X SAID AT THAT TIME THAT HE WILL NOT BE ABLE TO BE LEVELED THAT SOON. I TURNED ACR Y TO A 270 DEG HDG. ACR X CALLED THAT TFC IN SIGHT AT 4 O'CLOCK. SEP WAS LOST WITH 1100' VERT SEP AND 3.125 MI LAT. C/A ACTIVATED AT XA15. AEDP WAS SET OFF AT XC09. THERE WERE 4 SECTORS ACTIVE OUT OF 7. THERE WERE 8 CTLRS AND 1 SUPVR (GIVING 1 OF THE CTLRS A CHK RIDE AT THE POSITIONS AND 9 CTLRS ON BREAK). OF THE PREVIOUS 9, 5 WERE FPL'S, 2 FULL MANUAL CTLRS AND 2 MANUAL CTLR TRNEES. THERE WERE 13 FDB ON THE PVD, 8 ACFT ON FREQ (2 ON RADAR VECTORS, 3 CLBING AND 0 DSNDING), 3 ACFT OFF FREQ AND 2 NEW DATA BLOCKS. OVERALL, IN MY JUDGEMENT, AN ERRONEOUS JUDGEMENT I MIGHT ADD, I HAD ABOUT 4 MINS BEFORE X WOULD BE A FACTOR WITH Y. HE (X) HAD ONLY 2000' TO GO BEFORE VERT SEP WOULD EXIST. I HAD TO TAKE CARE OF OTHER TFC SITUATIONS AND DID NOT GET BACK TO THIS SITUATION ON TIME TO ACCOMPLISH SEP.

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.