Narrative:

We were cruising at FL350 in the vicinity of sbn VOR. The flight was on radar vectors from chicago center, and a clearance was received to climb to FL370 and turn immediately to 180 degree. Within seconds of the receipt of this clearance, traffic was sighted at the 2 O'clock position and a collision seemed imminent. I initiated a hard 'push-over' to avoid the traffic. After the aircraft was stabilized from the evasive maneuver, I learned that there were passenger injuries during the maneuver. The passenger injuries were not life-threatening and the flight returned to stl. The NTSB initial hearing and the chicago center tapes would seem to indicate that we acknowledged a clearance for radar vectors that was intended for another aircraft. The clearance read back was loud and clear, but obviously the pilots and the ATC controller missed the error. Supplemental information from acn 121927: I 'quick looked' fwa high sector from the ord scope. I noticed 'conflict alert' between air carrier X and a military aircraft. I went immediately to the fwa high sector. There was about 12 aircraft in or near the sector. The 2 aircraft in question were about 10 mi apart, converging at nearly a 90 degree angle both at FL350. I asked the radar controller what he had done about the 2 aircraft. He replied that he 'had air carrier X going up...'. I thought about ordering this controller to descend the military aircraft but the aircraft were so close -- both still showing FL350, that I felt such an order could make that situation worse it the pilots took evasive action on their own. After the aircraft passed, both pilots reported the near miss.

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Original NASA ASRS Text

Title: ACR TOOK CLRNC INTENDED FOR ANOTHER ACFT AND HAD NEAR MISS WITH A MLT.

Narrative: WE WERE CRUISING AT FL350 IN THE VICINITY OF SBN VOR. THE FLT WAS ON RADAR VECTORS FROM CHICAGO CENTER, AND A CLRNC WAS RECEIVED TO CLIMB TO FL370 AND TURN IMMEDIATELY TO 180 DEG. WITHIN SECONDS OF THE RECEIPT OF THIS CLRNC, TFC WAS SIGHTED AT THE 2 O'CLOCK POSITION AND A COLLISION SEEMED IMMINENT. I INITIATED A HARD 'PUSH-OVER' TO AVOID THE TFC. AFTER THE ACFT WAS STABILIZED FROM THE EVASIVE MANEUVER, I LEARNED THAT THERE WERE PAX INJURIES DURING THE MANEUVER. THE PAX INJURIES WERE NOT LIFE-THREATENING AND THE FLT RETURNED TO STL. THE NTSB INITIAL HEARING AND THE CHICAGO CENTER TAPES WOULD SEEM TO INDICATE THAT WE ACKNOWLEDGED A CLRNC FOR RADAR VECTORS THAT WAS INTENDED FOR ANOTHER ACFT. THE CLRNC READ BACK WAS LOUD AND CLEAR, BUT OBVIOUSLY THE PLTS AND THE ATC CTLR MISSED THE ERROR. SUPPLEMENTAL INFORMATION FROM ACN 121927: I 'QUICK LOOKED' FWA HIGH SECTOR FROM THE ORD SCOPE. I NOTICED 'CONFLICT ALERT' BETWEEN ACR X AND A MIL ACFT. I WENT IMMEDIATELY TO THE FWA HIGH SECTOR. THERE WAS ABOUT 12 ACFT IN OR NEAR THE SECTOR. THE 2 ACFT IN QUESTION WERE ABOUT 10 MI APART, CONVERGING AT NEARLY A 90 DEG ANGLE BOTH AT FL350. I ASKED THE RADAR CTLR WHAT HE HAD DONE ABOUT THE 2 ACFT. HE REPLIED THAT HE 'HAD ACR X GOING UP...'. I THOUGHT ABOUT ORDERING THIS CTLR TO DSND THE MIL ACFT BUT THE ACFT WERE SO CLOSE -- BOTH STILL SHOWING FL350, THAT I FELT SUCH AN ORDER COULD MAKE THAT SITUATION WORSE IT THE PLTS TOOK EVASIVE ACTION ON THEIR OWN. AFTER THE ACFT PASSED, BOTH PLTS REPORTED THE NEAR MISS.

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.