Narrative:

We were on a right downwind for runway 27, iah, level at an assigned altitude of 6000' and on an assigned heading of 080 degrees. The approach controller called out traffic at 2 O'clock, climbing from 4000 to 5000'. We called him in sight. He appeared to be on a roughly parallel course well below us. Approximately 1 min later we looked out the right side and saw large transport Y coming directly at us, climbing through our altitude. Any maneuver on my part other than a descent would have aggravated the situation. Prior to commencing a descent to avoid the other aircraft, we observed him commence a hard left turn and realized he would pass behind us. I estimate that he came within 1/2 mi at the closest point. I reported the incident immediately to the approach controller and, when on the ground, I called the area manager, and discussed the incident. He told me that they (departure control) had climbed him through my altitude. Callback conversation with reporter revealed the following: as stated in narrative, reporter called the TRACON by telephone and learned that the departure controller had mistakenly climbed a departure through the arrival corridor. The climbing departure passed approximately 1/2 mi behind reporter's aircraft at the same altitude.

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Original NASA ASRS Text

Title: ACR-LGT VECOTRED AND CLIMBED INTO CONFLICT WITH ACR-LGT ARR RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: WE WERE ON A RIGHT DOWNWIND FOR RWY 27, IAH, LEVEL AT AN ASSIGNED ALT OF 6000' AND ON AN ASSIGNED HDG OF 080 DEGS. THE APCH CTLR CALLED OUT TFC AT 2 O'CLOCK, CLBING FROM 4000 TO 5000'. WE CALLED HIM IN SIGHT. HE APPEARED TO BE ON A ROUGHLY PARALLEL COURSE WELL BELOW US. APPROX 1 MIN LATER WE LOOKED OUT THE RIGHT SIDE AND SAW LGT Y COMING DIRECTLY AT US, CLBING THROUGH OUR ALT. ANY MANEUVER ON MY PART OTHER THAN A DSCNT WOULD HAVE AGGRAVATED THE SITUATION. PRIOR TO COMMENCING A DSCNT TO AVOID THE OTHER ACFT, WE OBSERVED HIM COMMENCE A HARD LEFT TURN AND REALIZED HE WOULD PASS BEHIND US. I ESTIMATE THAT HE CAME WITHIN 1/2 MI AT THE CLOSEST POINT. I RPTED THE INCIDENT IMMEDIATELY TO THE APCH CTLR AND, WHEN ON THE GND, I CALLED THE AREA MGR, AND DISCUSSED THE INCIDENT. HE TOLD ME THAT THEY (DEP CTL) HAD CLBED HIM THROUGH MY ALT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: AS STATED IN NARRATIVE, RPTR CALLED THE TRACON BY TELEPHONE AND LEARNED THAT THE DEP CTLR HAD MISTAKENLY CLBED A DEP THROUGH THE ARR CORRIDOR. THE CLBING DEP PASSED APPROX 1/2 MI BEHIND RPTR'S ACFT AT THE SAME ALT.

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.