Narrative:

Small aircraft X was VFR through the TCA. From a point approximately 6 mi wnw of msy he requested to fly back eastbound then overfly the airport then southwest on course. He requested this because he did not think he would be able to maintain VFR on his present course. I approved his request and advised I would inform him of inbound traffic. I became distracted by another TCA aircraft from the southeast and air carrier Z departing runway 19. I had to provide sep between these 2 aircraft. After sep was ensured the departure was switched to the radar controller. The departure did not acknowledge the frequency change. I was also occupied with 3 other departures and 3 arrs excluding the 2 aircraft involved in the sep error. I made 3 more attempts to get an acknowledgement from the departing air carrier Z. After asking the radar controller if he was talking to the departure, his reply was 'no.' I had forgotten about X when I realized the error was occurring I tried to issue traffic to inbound air carrier Y. I realized at that time I was too late and the 2 aircraft were separating. Conclusions: first, I should have instructed X to remain west of the inbound corridor of runway 19. Second, I spent too much time worrying if air carrier Z, departure, received the frequency change. Third, my scanning techniques of the BRITE radar scope were insufficient. I do not know how much vertical sep existed between the 2 aircraft. The pilot of Y saw X and after talking to the supervisor, did not voice a great deal of concern. The seriousness of the incident has given me much concern.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION AND NMAC BETWEEN SMA AND ACR. OPERATIONAL ERROR.

Narrative: SMA X WAS VFR THROUGH THE TCA. FROM A POINT APPROX 6 MI WNW OF MSY HE REQUESTED TO FLY BACK EBND THEN OVERFLY THE ARPT THEN SW ON COURSE. HE REQUESTED THIS BECAUSE HE DID NOT THINK HE WOULD BE ABLE TO MAINTAIN VFR ON HIS PRESENT COURSE. I APPROVED HIS REQUEST AND ADVISED I WOULD INFORM HIM OF INBND TFC. I BECAME DISTRACTED BY ANOTHER TCA ACFT FROM THE SE AND ACR Z DEPARTING RWY 19. I HAD TO PROVIDE SEP BTWN THESE 2 ACFT. AFTER SEP WAS ENSURED THE DEP WAS SWITCHED TO THE RADAR CTLR. THE DEP DID NOT ACKNOWLEDGE THE FREQ CHANGE. I WAS ALSO OCCUPIED WITH 3 OTHER DEPS AND 3 ARRS EXCLUDING THE 2 ACFT INVOLVED IN THE SEP ERROR. I MADE 3 MORE ATTEMPTS TO GET AN ACKNOWLEDGEMENT FROM THE DEPARTING ACR Z. AFTER ASKING THE RADAR CTLR IF HE WAS TALKING TO THE DEP, HIS REPLY WAS 'NO.' I HAD FORGOTTEN ABOUT X WHEN I REALIZED THE ERROR WAS OCCURRING I TRIED TO ISSUE TFC TO INBND ACR Y. I REALIZED AT THAT TIME I WAS TOO LATE AND THE 2 ACFT WERE SEPARATING. CONCLUSIONS: FIRST, I SHOULD HAVE INSTRUCTED X TO REMAIN W OF THE INBND CORRIDOR OF RWY 19. SECOND, I SPENT TOO MUCH TIME WORRYING IF ACR Z, DEP, RECEIVED THE FREQ CHANGE. THIRD, MY SCANNING TECHNIQUES OF THE BRITE RADAR SCOPE WERE INSUFFICIENT. I DO NOT KNOW HOW MUCH VERT SEP EXISTED BTWN THE 2 ACFT. THE PLT OF Y SAW X AND AFTER TALKING TO THE SUPVR, DID NOT VOICE A GREAT DEAL OF CONCERN. THE SERIOUSNESS OF THE INCIDENT HAS GIVEN ME MUCH CONCERN.

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.