Narrative:

The large transport had every seat full. We had 2 cockpit crew members (a captain and a copilot) riding in the jump seats. We needed runway 31 because of weight. We received takeoff clearance with instructions to maintain runway heading until 2 DME then right to 340 and stay with tower, which we did. At about 1000 AGL, tower instructed us to give him a good rate of climb for traffic. At about 2000 AGL, traffic was pointed out at our 2 O'clock position and 2 or 3 mi. We were told that the traffic had us in sight and would maintain visual separation. At about 2400 AGL, one of the deadheading crew members spotted the light plane (an small aircraft). I, however, still couldn't see because of our high nose attitude. Another crew member spotted the light plane and said 'this one is really close.' I got up in my seat to get a better view and saw how close the plane actually was. Then I pulled back on the controls and looked to the TCASII (it was in TA only position) for some guidance. According to our TCASII, the plane passed 100 ft below us. I then got on the radio with the tower and told him what had happened. He told us that the light plane had us in sight and was supposed to maintain visual separation. During the flight to ord, the other crew members and I had a chance to talk about what had happened. I had a visual on the aircraft for the least amount of time and was told by the other crew members that it was the closest that nay of them had come to a midair. They also thought that the TCASII was accurate. Based on what they saw, what I saw, and what the TCASII was telling us, I believe that we had come within 100 or 200 ft of having a midair collision!!! Conversations with the tower chief from bna, the following day confirmed that: 1) our aircraft passed within 200 ft of the other aircraft!!! 2) the other aircraft had begun a descent in order to avoid us. 3) the fault rests solely with the pilot of the light plane to maintain adequate separation.

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Original NASA ASRS Text

Title: NMAC BTWN AN ACR LGT ON DEP AND AN SMA IN ATA XING DEP RTE.

Narrative: THE LGT HAD EVERY SEAT FULL. WE HAD 2 COCKPIT CREW MEMBERS (A CAPT AND A COPLT) RIDING IN THE JUMP SEATS. WE NEEDED RWY 31 BECAUSE OF WT. WE RECEIVED TKOF CLRNC WITH INSTRUCTIONS TO MAINTAIN RWY HDG UNTIL 2 DME THEN R TO 340 AND STAY WITH TWR, WHICH WE DID. AT ABOUT 1000 AGL, TWR INSTRUCTED US TO GIVE HIM A GOOD RATE OF CLB FOR TFC. AT ABOUT 2000 AGL, TFC WAS POINTED OUT AT OUR 2 O'CLOCK POS AND 2 OR 3 MI. WE WERE TOLD THAT THE TFC HAD US IN SIGHT AND WOULD MAINTAIN VISUAL SEPARATION. AT ABOUT 2400 AGL, ONE OF THE DEADHEADING CREW MEMBERS SPOTTED THE LIGHT PLANE (AN SMA). I, HOWEVER, STILL COULDN'T SEE BECAUSE OF OUR HIGH NOSE ATTITUDE. ANOTHER CREW MEMBER SPOTTED THE LIGHT PLANE AND SAID 'THIS ONE IS REALLY CLOSE.' I GOT UP IN MY SEAT TO GET A BETTER VIEW AND SAW HOW CLOSE THE PLANE ACTUALLY WAS. THEN I PULLED BACK ON THE CTLS AND LOOKED TO THE TCASII (IT WAS IN TA ONLY POS) FOR SOME GUIDANCE. ACCORDING TO OUR TCASII, THE PLANE PASSED 100 FT BELOW US. I THEN GOT ON THE RADIO WITH THE TWR AND TOLD HIM WHAT HAD HAPPENED. HE TOLD US THAT THE LIGHT PLANE HAD US IN SIGHT AND WAS SUPPOSED TO MAINTAIN VISUAL SEPARATION. DURING THE FLT TO ORD, THE OTHER CREW MEMBERS AND I HAD A CHANCE TO TALK ABOUT WHAT HAD HAPPENED. I HAD A VISUAL ON THE ACFT FOR THE LEAST AMOUNT OF TIME AND WAS TOLD BY THE OTHER CREW MEMBERS THAT IT WAS THE CLOSEST THAT NAY OF THEM HAD COME TO A MIDAIR. THEY ALSO THOUGHT THAT THE TCASII WAS ACCURATE. BASED ON WHAT THEY SAW, WHAT I SAW, AND WHAT THE TCASII WAS TELLING US, I BELIEVE THAT WE HAD COME WITHIN 100 OR 200 FT OF HAVING A MIDAIR COLLISION!!! CONVERSATIONS WITH THE TWR CHIEF FROM BNA, THE FOLLOWING DAY CONFIRMED THAT: 1) OUR ACFT PASSED WITHIN 200 FT OF THE OTHER ACFT!!! 2) THE OTHER ACFT HAD BEGUN A DSCNT IN ORDER TO AVOID US. 3) THE FAULT RESTS SOLELY WITH THE PLT OF THE LIGHT PLANE TO MAINTAIN ADEQUATE SEPARATION.

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.