Narrative:

I was training a developmental on both macon radar (sfc- 30 within 20 NM of mcn) and mcn low (sfc-50 within approximately 40 NM). The WX was IFR and traffic was mostly light. The aircraft involved in the pilot deviation small aircraft X had been holding over the mcn VOR, IFR at 4000. The pilot was given a vector southwest of mcn so we could release a KR35 off wrb nwbound. Small aircraft X requested a full NDB runway 05 approach at the mcn airport and my developmental was not aware of this request. Small aircraft X continued sbound and a few mins later made his request again. My developmental told the pilot to proceed direct to sofke. There was another aircraft 4 NM northwest of mcn at 2200 nwbound requesting an ILS runway 05 approach. As small aircraft X approached sofke I asked the developmental what his plan was and if he intended on having small aircraft X descend to 3200 and proceed outbound on the approach to follow the other aircraft small aircraft Y on the ILS approach. However I felt that small aircraft X could and should be #1 in the sequence and advised the developmental to clear small aircraft X for the approach. He did, bu the pilot did not respond. Soon after the clearance was issued the pilot began a turn northbound at 3200 heading for small aircraft Y at 2200. Observing this I told the developmental to cancel small aircraft X approach clearance and tell him to maintain 3200. Small aircraft X then said 'roger, maintain 3200.' small aircraft X stated that he wanted to maneuver north then proceed direct to sofke. Small aircraft Y was turned swbound and my developmental and I agreed that small aircraft Y would now be #1 on the approach. Over the next couple of mins several things happened. We had an aircraft miss approach at the dbn airport wanting WX information for both mcn and ags. Another aircraft pop up over vna at 1500 looking for an IFR clearance, an IFR departure off mlj direct to culvr and small aircraft X reporting over sofke at 3200 outbound. By this time small aircraft Y was 12 NM southwest of mcn on base and was given a turn inbound for the ILS. I was so sure, without a doubt in my mind, that small aircraft X knew that he still had an altitude restr of 3200 that I felt like I didn't have to pay attention to that situation because I knew everything was okay. We went about issuing clrnces , etc and the next thing I knew the conflict alert was going off. I looked and small aircraft X and small aircraft Y were head on separated by 300 ft. I asked small aircraft X to verify his altitude, he started to talk then quit in mid sentence as their primary targets were merging, and I knew they didn't have a prayer. I observed their targets separate and asked small aircraft X to again verify his altitude and he replied 2000 ft. I told him that he was assigned 3200 and had him climb back to 3200 because he was now #3 to the airport. I was sure the pilot knew about his altitude restr of 3200 that he was not issued an approach clearance and the pilot said later that he was sure that he was cleared for the approach. Moral of the story -- never, ever assume anything! Reiterate an altitude restr if it is necessary. Never stop scanning any traffic for any reason. And if you're a pilot, if you think you've been issued an approach clearance but don't know for sure, always ask! That's what we're here for!

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Original NASA ASRS Text

Title: SMA PLT FORGOT HE WAS TO MAINTAIN HIS ALT AND HAD AN NMAC WITH ANOTHER SMA ON APCH. CTLR TRAINING IN PROGRESS AND TFC NOT GIVEN.

Narrative: I WAS TRAINING A DEVELOPMENTAL ON BOTH MACON RADAR (SFC- 30 WITHIN 20 NM OF MCN) AND MCN LOW (SFC-50 WITHIN APPROX 40 NM). THE WX WAS IFR AND TFC WAS MOSTLY LIGHT. THE ACFT INVOLVED IN THE PLT DEV SMA X HAD BEEN HOLDING OVER THE MCN VOR, IFR AT 4000. THE PLT WAS GIVEN A VECTOR SW OF MCN SO WE COULD RELEASE A KR35 OFF WRB NWBOUND. SMA X REQUESTED A FULL NDB RWY 05 APCH AT THE MCN ARPT AND MY DEVELOPMENTAL WAS NOT AWARE OF THIS REQUEST. SMA X CONTINUED SBOUND AND A FEW MINS LATER MADE HIS REQUEST AGAIN. MY DEVELOPMENTAL TOLD THE PLT TO PROCEED DIRECT TO SOFKE. THERE WAS ANOTHER ACFT 4 NM NW OF MCN AT 2200 NWBOUND REQUESTING AN ILS RWY 05 APCH. AS SMA X APCHED SOFKE I ASKED THE DEVELOPMENTAL WHAT HIS PLAN WAS AND IF HE INTENDED ON HAVING SMA X DSND TO 3200 AND PROCEED OUTBOUND ON THE APCH TO FOLLOW THE OTHER ACFT SMA Y ON THE ILS APCH. HOWEVER I FELT THAT SMA X COULD AND SHOULD BE #1 IN THE SEQUENCE AND ADVISED THE DEVELOPMENTAL TO CLR SMA X FOR THE APCH. HE DID, BU THE PLT DID NOT RESPOND. SOON AFTER THE CLRNC WAS ISSUED THE PLT BEGAN A TURN NBOUND AT 3200 HDG FOR SMA Y AT 2200. OBSERVING THIS I TOLD THE DEVELOPMENTAL TO CANCEL SMA X APCH CLRNC AND TELL HIM TO MAINTAIN 3200. SMA X THEN SAID 'ROGER, MAINTAIN 3200.' SMA X STATED THAT HE WANTED TO MANEUVER N THEN PROCEED DIRECT TO SOFKE. SMA Y WAS TURNED SWBOUND AND MY DEVELOPMENTAL AND I AGREED THAT SMA Y WOULD NOW BE #1 ON THE APCH. OVER THE NEXT COUPLE OF MINS SEVERAL THINGS HAPPENED. WE HAD AN ACFT MISS APCH AT THE DBN ARPT WANTING WX INFO FOR BOTH MCN AND AGS. ANOTHER ACFT POP UP OVER VNA AT 1500 LOOKING FOR AN IFR CLRNC, AN IFR DEP OFF MLJ DIRECT TO CULVR AND SMA X RPTING OVER SOFKE AT 3200 OUTBOUND. BY THIS TIME SMA Y WAS 12 NM SW OF MCN ON BASE AND WAS GIVEN A TURN INBOUND FOR THE ILS. I WAS SO SURE, WITHOUT A DOUBT IN MY MIND, THAT SMA X KNEW THAT HE STILL HAD AN ALT RESTR OF 3200 THAT I FELT LIKE I DIDN'T HAVE TO PAY ATTENTION TO THAT SIT BECAUSE I KNEW EVERYTHING WAS OKAY. WE WENT ABOUT ISSUING CLRNCES , ETC AND THE NEXT THING I KNEW THE CONFLICT ALERT WAS GOING OFF. I LOOKED AND SMA X AND SMA Y WERE HEAD ON SEPARATED BY 300 FT. I ASKED SMA X TO VERIFY HIS ALT, HE STARTED TO TALK THEN QUIT IN MID SENTENCE AS THEIR PRIMARY TARGETS WERE MERGING, AND I KNEW THEY DIDN'T HAVE A PRAYER. I OBSERVED THEIR TARGETS SEPARATE AND ASKED SMA X TO AGAIN VERIFY HIS ALT AND HE REPLIED 2000 FT. I TOLD HIM THAT HE WAS ASSIGNED 3200 AND HAD HIM CLB BACK TO 3200 BECAUSE HE WAS NOW #3 TO THE ARPT. I WAS SURE THE PLT KNEW ABOUT HIS ALT RESTR OF 3200 THAT HE WAS NOT ISSUED AN APCH CLRNC AND THE PLT SAID LATER THAT HE WAS SURE THAT HE WAS CLRED FOR THE APCH. MORAL OF THE STORY -- NEVER, EVER ASSUME ANYTHING! REITERATE AN ALT RESTR IF IT IS NECESSARY. NEVER STOP SCANNING ANY TFC FOR ANY REASON. AND IF YOU'RE A PLT, IF YOU THINK YOU'VE BEEN ISSUED AN APCH CLRNC BUT DON'T KNOW FOR SURE, ALWAYS ASK! THAT'S WHAT WE'RE HERE FOR!

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.