Narrative:

While descending into btr at approximately 8500' on the btr 290 degrees/20 DME traffic small aircraft was called out at 11 O'clock and 5 mi. We were called out to small aircraft at the same time. We acknowledged that we did not see him, however he responded that he had visibility contact with us. We had all available lights on. Approximately 1 1/2 mins later small aircraft stated he would level at 7500'. We continued to look for him and then suddenly at 12 O'clock to our position heading directly at us at 1/8 of a mi he appeared. I pulled back on my elevator to stop my descent at 7600'. Small aircraft passed below me at no more than 100' vertical sep and 0' horizontal sep. This event took no more than 3 seconds. I contacted the supervisor on duty at baton rouge approach control and initiated appropriate near miss report procedures. This problem arose out of a belief upon the part of the supervisor on duty in the btr approach control that less than required sep between converging aircraft can occur if one of the aircraft has visibility contact with the other. This procedure or philosophy is fatally flawed and will result in future tragedy. If 2 aircraft are on a collision course one or both aircraft whether IFR or VFR need to be issued avoidance vectors in all situations. Total tragedy was averted in this situation due to a last split second visibility sighting. We may not be so fortunate if this situation occurs again.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG GA-SMA.

Narrative: WHILE DSNDING INTO BTR AT APPROX 8500' ON THE BTR 290 DEGS/20 DME TFC SMA WAS CALLED OUT AT 11 O'CLOCK AND 5 MI. WE WERE CALLED OUT TO SMA AT THE SAME TIME. WE ACKNOWLEDGED THAT WE DID NOT SEE HIM, HOWEVER HE RESPONDED THAT HE HAD VIS CONTACT WITH US. WE HAD ALL AVAILABLE LIGHTS ON. APPROX 1 1/2 MINS LATER SMA STATED HE WOULD LEVEL AT 7500'. WE CONTINUED TO LOOK FOR HIM AND THEN SUDDENLY AT 12 O'CLOCK TO OUR POS HDG DIRECTLY AT US AT 1/8 OF A MI HE APPEARED. I PULLED BACK ON MY ELEVATOR TO STOP MY DSCNT AT 7600'. SMA PASSED BELOW ME AT NO MORE THAN 100' VERT SEP AND 0' HORIZ SEP. THIS EVENT TOOK NO MORE THAN 3 SECS. I CONTACTED THE SUPVR ON DUTY AT BATON ROUGE APCH CTL AND INITIATED APPROPRIATE NEAR MISS RPT PROCS. THIS PROB AROSE OUT OF A BELIEF UPON THE PART OF THE SUPVR ON DUTY IN THE BTR APCH CTL THAT LESS THAN REQUIRED SEP BTWN CONVERGING ACFT CAN OCCUR IF ONE OF THE ACFT HAS VIS CONTACT WITH THE OTHER. THIS PROC OR PHILOSOPHY IS FATALLY FLAWED AND WILL RESULT IN FUTURE TRAGEDY. IF 2 ACFT ARE ON A COLLISION COURSE ONE OR BOTH ACFT WHETHER IFR OR VFR NEED TO BE ISSUED AVOIDANCE VECTORS IN ALL SITUATIONS. TOTAL TRAGEDY WAS AVERTED IN THIS SITUATION DUE TO A LAST SPLIT SECOND VIS SIGHTING. WE MAY NOT BE SO FORTUNATE IF THIS SITUATION OCCURS AGAIN.

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.