Narrative:

Small transport X was en route from ord to eok. Malta sector is required to point aircraft out to plano sector if aircraft gets within 2.5 mi before entering brl sector. If airplane is more than 2.5 mi from plano sector, then brl makes pointout to plano. Neither brl nor malta made pointout to plano. Plano descended medium large transport Y from 15000 ft to 13000 ft. 2 airplanes were less than 5 mi and less than 1000 ft. Boundary should be changed so aircraft don't enter brl sector and then immediately exit into plano sector and then back to brl. Supplemental information from acn 378376: ZAU51 descended medium large transport Y from 15000 ft to 13000 ft on V8 eastbound which resulted in loss of separation as small transport X passed 4 mi behind medium large transport Y. There was no conflict alert until loss of separation occurred and I had not noticed the limited data block of small transport X turning into my airspace. There is a design flaw in the airspace which contributed to this error and needs to be redesigned, since this problem has been an ongoing one.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLRS FAILED TO MAKE A POINTOUT TO AN ADJACENT SECTOR ON A BE20 GOING DIRECT TO EOK THAT WOULD BE CLIPPING THAT SECTOR'S AIRSPACE. THE ADJACENT SECTOR CTLR DSNDED A G4 THROUGH THE BE20 ALT AND LOST SEPARATION BEFORE THE CONFLICT ALERT ACTIVATED. 2 RPTING CTLRS SAY AIRSPACE DESIGN CONTRIBUTED TO THIS ERROR.

Narrative: SMT X WAS ENRTE FROM ORD TO EOK. MALTA SECTOR IS REQUIRED TO POINT ACFT OUT TO PLANO SECTOR IF ACFT GETS WITHIN 2.5 MI BEFORE ENTERING BRL SECTOR. IF AIRPLANE IS MORE THAN 2.5 MI FROM PLANO SECTOR, THEN BRL MAKES POINTOUT TO PLANO. NEITHER BRL NOR MALTA MADE POINTOUT TO PLANO. PLANO DSNDED MLG Y FROM 15000 FT TO 13000 FT. 2 AIRPLANES WERE LESS THAN 5 MI AND LESS THAN 1000 FT. BOUNDARY SHOULD BE CHANGED SO ACFT DON'T ENTER BRL SECTOR AND THEN IMMEDIATELY EXIT INTO PLANO SECTOR AND THEN BACK TO BRL. SUPPLEMENTAL INFO FROM ACN 378376: ZAU51 DSNDED MLG Y FROM 15000 FT TO 13000 FT ON V8 EBOUND WHICH RESULTED IN LOSS OF SEPARATION AS SMT X PASSED 4 MI BEHIND MLG Y. THERE WAS NO CONFLICT ALERT UNTIL LOSS OF SEPARATION OCCURRED AND I HAD NOT NOTICED THE LIMITED DATA BLOCK OF SMT X TURNING INTO MY AIRSPACE. THERE IS A DESIGN FLAW IN THE AIRSPACE WHICH CONTRIBUTED TO THIS ERROR AND NEEDS TO BE REDESIGNED, SINCE THIS PROB HAS BEEN AN ONGOING ONE.

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.