Narrative:

Small transport X level at FL180 on J80, 15 mi southwest of etx VORTAC, proceeding swbound (ground speed was about 200 KTS). Sector 11 called for a pointout of medium large transport Y (32Q KTS G/south), located over the ptw VORTAC nwbound on the ptw 320 degree right to intercept J64 and proceed wbound. Medium large transport Y was out of 15000' for 17000'. Sector 11 requested control to climb to FL260. I approved the pointout west/O referencing small transport X. I felt that medium large transport Y would go behind and above small transport X. I became involved with other traffic in another part of my sector, not noticing the very poor climb rate and increase of speed on medium large transport Y. The C/a did not go off until there was 4.9 mi. The aircraft (medium large transport Y) passed behind small transport X with 4.4 mi latitude sep at 200' vertical sep. No corrective or evasive action was taken, or necessary, since the aircraft had already passed and were on diverging courses. I feel I could have avoided the entire situation of just referencing small transport X and not assuming (bad word in ATC!!!) medium large transport Y would pass behind and above small transport X. Positive sep must be maintained at all times. I learned another valuable lesson for this situation, so at least some good comes out of it.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION WHEN ACR-MLG IS ALLOWED TO CLIMB THROUGH THE ALT OF CPR-SMT.

Narrative: SMT X LEVEL AT FL180 ON J80, 15 MI SW OF ETX VORTAC, PROCEEDING SWBOUND (GND SPD WAS ABOUT 200 KTS). SECTOR 11 CALLED FOR A POINTOUT OF MLG Y (32Q KTS G/S), LOCATED OVER THE PTW VORTAC NWBOUND ON THE PTW 320 DEG R TO INTERCEPT J64 AND PROCEED WBOUND. MLG Y WAS OUT OF 15000' FOR 17000'. SECTOR 11 REQUESTED CTL TO CLB TO FL260. I APPROVED THE POINTOUT W/O REFERENCING SMT X. I FELT THAT MLG Y WOULD GO BEHIND AND ABOVE SMT X. I BECAME INVOLVED WITH OTHER TFC IN ANOTHER PART OF MY SECTOR, NOT NOTICING THE VERY POOR CLB RATE AND INCREASE OF SPD ON MLG Y. THE C/A DID NOT GO OFF UNTIL THERE WAS 4.9 MI. THE ACFT (MLG Y) PASSED BEHIND SMT X WITH 4.4 MI LAT SEP AT 200' VERT SEP. NO CORRECTIVE OR EVASIVE ACTION WAS TAKEN, OR NECESSARY, SINCE THE ACFT HAD ALREADY PASSED AND WERE ON DIVERGING COURSES. I FEEL I COULD HAVE AVOIDED THE ENTIRE SITUATION OF JUST REFERENCING SMT X AND NOT ASSUMING (BAD WORD IN ATC!!!) MLG Y WOULD PASS BEHIND AND ABOVE SMT X. POSITIVE SEP MUST BE MAINTAINED AT ALL TIMES. I LEARNED ANOTHER VALUABLE LESSON FOR THIS SITUATION, SO AT LEAST SOME GOOD COMES OUT OF IT.

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.