Narrative:

I was working the mdw sector 3 position responsible for mdw north and west departures and several small airports southwest of O'hare. As procedures dictate, I had a northbound jet depart, so I coordinated a climb to 6000 ft with the O'hare sbound controller. I was told to go up under his only sbound. A few moments later, the O'hare south departure called back telling me to stay under his second sbound departure, just airborne. I told him I could stay at 5000 ft so he could get the #2 sbound climbing. I was busy with other aircraft and did not get back to the northbound as quickly as I should have to climb it to 6000 ft, as the altitude became available. Even though I had pointed out the northbound to the O'hare south departure controller and he should have seen my traffic still at 5000 ft (the initial altitude all ord departures climb to), he allowed his third sbound to climb to 5000 ft instead of stopping below me. Then he issued a tight left turn from a 220 degree heading to a 140 degree heading that brought the regional jet into the path of my northbound B727 both at 5000 ft. The south controller called me again asking if the northbound was going up. At that moment, I climbed the northbound to 6000 ft and issued a turn to 040 degrees to stay away from #3 sbound, unaware that traffic was turned into mine. Visual separation was applied when the aircraft were about 3 mi apart. They missed by less than 1 mi and 200 ft. Conflict alert did not go off until the aircraft started coming apart.

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Original NASA ASRS Text

Title: A DEP CTLR RPT ON A POTENTIAL CONFLICT BTWN 2 ACFT CLBING TO THE SAME ALT 8 MI SW OF ORD, IL.

Narrative: I WAS WORKING THE MDW SECTOR 3 POS RESPONSIBLE FOR MDW N AND W DEPS AND SEVERAL SMALL ARPTS SW OF O'HARE. AS PROCS DICTATE, I HAD A NBOUND JET DEPART, SO I COORDINATED A CLB TO 6000 FT WITH THE O'HARE SBOUND CTLR. I WAS TOLD TO GO UP UNDER HIS ONLY SBOUND. A FEW MOMENTS LATER, THE O'HARE S DEP CALLED BACK TELLING ME TO STAY UNDER HIS SECOND SBOUND DEP, JUST AIRBORNE. I TOLD HIM I COULD STAY AT 5000 FT SO HE COULD GET THE #2 SBOUND CLBING. I WAS BUSY WITH OTHER ACFT AND DID NOT GET BACK TO THE NBOUND AS QUICKLY AS I SHOULD HAVE TO CLB IT TO 6000 FT, AS THE ALT BECAME AVAILABLE. EVEN THOUGH I HAD POINTED OUT THE NBOUND TO THE O'HARE S DEP CTLR AND HE SHOULD HAVE SEEN MY TFC STILL AT 5000 FT (THE INITIAL ALT ALL ORD DEPS CLB TO), HE ALLOWED HIS THIRD SBOUND TO CLB TO 5000 FT INSTEAD OF STOPPING BELOW ME. THEN HE ISSUED A TIGHT L TURN FROM A 220 DEG HDG TO A 140 DEG HDG THAT BROUGHT THE REGIONAL JET INTO THE PATH OF MY NBOUND B727 BOTH AT 5000 FT. THE S CTLR CALLED ME AGAIN ASKING IF THE NBOUND WAS GOING UP. AT THAT MOMENT, I CLBED THE NBOUND TO 6000 FT AND ISSUED A TURN TO 040 DEGS TO STAY AWAY FROM #3 SBOUND, UNAWARE THAT TFC WAS TURNED INTO MINE. VISUAL SEPARATION WAS APPLIED WHEN THE ACFT WERE ABOUT 3 MI APART. THEY MISSED BY LESS THAN 1 MI AND 200 FT. CONFLICT ALERT DID NOT GO OFF UNTIL THE ACFT STARTED COMING APART.

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.