Narrative:

There was a near midair collision about 10 mi south of rhinelander, wi. The involved aircraft were cga X, who had just departed rhi, and small aircraft Y, who was going into arv and had cancelled his IFR a few mins earlier. As he was passing through 5000', small aircraft Y cancelled his IFR. I acknowledged his cancellation and cleared him off frequency. A short time after this cga X called again at rhi, ready to go this time. Both small aircraft Y and small aircraft Z were still well southeast of rhi. Therefore, I cleared cga X to tol to climb and maintain 4000'. A while passed and small aircraft Z and small aircraft Y were now about 15 mi south of rhi. I told small aircraft Z about cga X coming off rhi and told him he could look for the tower. Cga X called off rhi. I idented him and gave him the traffic as 2 small aircraft targets south of rhi, about 12 mi. One was IFR at 5000', the other was VFR showing (I don't remember for sure, but I think it was) 4400'. Cga X responded that he had the traffic. I believe I then went back and gave small aircraft Z the cga traffic, but I'm not sure on this. I then went to look at the situation at rhi. I saw cga X and small aircraft Y head-on, with maybe 1 mi apart now, with cga X showing at 4100' and small aircraft Y showing at about 4200'. I asked (to verify) cga X if he was sure he had the traffic at 12 O'clock and less than 1 mi at the same altitude? He said he had the traffic at his 11 O'clock and high. I told him that that was his IFR traffic at 5000', and that he had traffic at 12 O'clock, same altitude and less than 1 mi. He responded that he didn't have the traffic. Then he came right back and said, 'I got him.' I went on to other tasks, but noticed that the VFR altitude readout of small aircraft Y immediately dropped to 3600'. Then cga X came back and reported that he had to take evasive action to miss that aircraft. I also believe from the mode C readout of small aircraft Y that he also took evasive actions. I told cga X that I would report the incident. I turned around and reported the incident to the area supervisor on duty at the destination. I got no response. I think if nothing else this report should have been filed by the FAA.

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Original NASA ASRS Text

Title: REPORTER UNHAPPY BECAUSE FAC WILL NOT FILE A NMAC ON AN ACFT THAT TOOK EVASIVE ACTION TO AVOID ANOTHER ACFT.

Narrative: THERE WAS A NMAC ABOUT 10 MI S OF RHINELANDER, WI. THE INVOLVED ACFT WERE CGA X, WHO HAD JUST DEPARTED RHI, AND SMA Y, WHO WAS GOING INTO ARV AND HAD CANCELLED HIS IFR A FEW MINS EARLIER. AS HE WAS PASSING THROUGH 5000', SMA Y CANCELLED HIS IFR. I ACKNOWLEDGED HIS CANCELLATION AND CLRED HIM OFF FREQ. A SHORT TIME AFTER THIS CGA X CALLED AGAIN AT RHI, READY TO GO THIS TIME. BOTH SMA Y AND SMA Z WERE STILL WELL SE OF RHI. THEREFORE, I CLRED CGA X TO TOL TO CLB AND MAINTAIN 4000'. A WHILE PASSED AND SMA Z AND SMA Y WERE NOW ABOUT 15 MI S OF RHI. I TOLD SMA Z ABOUT CGA X COMING OFF RHI AND TOLD HIM HE COULD LOOK FOR THE TWR. CGA X CALLED OFF RHI. I IDENTED HIM AND GAVE HIM THE TFC AS 2 SMA TARGETS S OF RHI, ABOUT 12 MI. ONE WAS IFR AT 5000', THE OTHER WAS VFR SHOWING (I DON'T REMEMBER FOR SURE, BUT I THINK IT WAS) 4400'. CGA X RESPONDED THAT HE HAD THE TFC. I BELIEVE I THEN WENT BACK AND GAVE SMA Z THE CGA TFC, BUT I'M NOT SURE ON THIS. I THEN WENT TO LOOK AT THE SITUATION AT RHI. I SAW CGA X AND SMA Y HEAD-ON, WITH MAYBE 1 MI APART NOW, WITH CGA X SHOWING AT 4100' AND SMA Y SHOWING AT ABOUT 4200'. I ASKED (TO VERIFY) CGA X IF HE WAS SURE HE HAD THE TFC AT 12 O'CLOCK AND LESS THAN 1 MI AT THE SAME ALT? HE SAID HE HAD THE TFC AT HIS 11 O'CLOCK AND HIGH. I TOLD HIM THAT THAT WAS HIS IFR TFC AT 5000', AND THAT HE HAD TFC AT 12 O'CLOCK, SAME ALT AND LESS THAN 1 MI. HE RESPONDED THAT HE DIDN'T HAVE THE TFC. THEN HE CAME RIGHT BACK AND SAID, 'I GOT HIM.' I WENT ON TO OTHER TASKS, BUT NOTICED THAT THE VFR ALT READOUT OF SMA Y IMMEDIATELY DROPPED TO 3600'. THEN CGA X CAME BACK AND RPTED THAT HE HAD TO TAKE EVASIVE ACTION TO MISS THAT ACFT. I ALSO BELIEVE FROM THE MODE C READOUT OF SMA Y THAT HE ALSO TOOK EVASIVE ACTIONS. I TOLD CGA X THAT I WOULD RPT THE INCIDENT. I TURNED AROUND AND RPTED THE INCIDENT TO THE AREA SUPVR ON DUTY AT THE DEST. I GOT NO RESPONSE. I THINK IF NOTHING ELSE THIS RPT SHOULD HAVE BEEN FILED BY THE FAA.

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.