Narrative:

Air carrier X, an light transport, was inbound for landing on runway 2. He was approximately 8 mi northwest of ric on an assigned heading of 160 degrees, descending out of 3000 for 2000'. Cpr Y, an small transport, departed runway 2 on a previously coordinated heading of 330 degrees, climbing to 3000'. Upon initial contact with cpr Y, I turned him left to a heading of 230 degrees and climbed him to 9000'. I called traffic (cpr Y) to air carrier X, who did not see the traffic. I turned cpr Y to a heading of 180 degrees, and told cpr Y about his traffic (air carrier X). Air carrier X reported the traffic in sight. I, however, did not instruct air carrier X to maintain visibility sep with cpr Y. The 2 aircraft passed 1.3 mi and 700' apart. This situation could easily have been prevented. Ric has procedures for arrival vs departure traffic. Arrs are usually kept at 4000' on downwind to allow departures to pass beneath at 3000'. Descending air carrier X was my first mistake, showing poor judgement. Inaction was the section mistake. Coordinating with the tower to assign cpr Y a different heading after descending air carrier X would have prevented this situation also. My last mistake was not instructing air carrier X to 'maintain visibility sep.' when air carrier X reported cpr Y, it's unsure whether standard sep was lost. However, west/O the above instructions, visibility sep is not considered to be in existence. Thus as air carrier X passed behind cpr Y visually, their targets came within 1.3 mi and 700', less than standard radar sep.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM CPR Y. SYSTEM ERROR.

Narrative: ACR X, AN LTT, WAS INBND FOR LNDG ON RWY 2. HE WAS APPROX 8 MI NW OF RIC ON AN ASSIGNED HDG OF 160 DEGS, DSNDING OUT OF 3000 FOR 2000'. CPR Y, AN SMT, DEPARTED RWY 2 ON A PREVIOUSLY COORDINATED HDG OF 330 DEGS, CLBING TO 3000'. UPON INITIAL CONTACT WITH CPR Y, I TURNED HIM LEFT TO A HDG OF 230 DEGS AND CLBED HIM TO 9000'. I CALLED TFC (CPR Y) TO ACR X, WHO DID NOT SEE THE TFC. I TURNED CPR Y TO A HDG OF 180 DEGS, AND TOLD CPR Y ABOUT HIS TFC (ACR X). ACR X RPTED THE TFC IN SIGHT. I, HOWEVER, DID NOT INSTRUCT ACR X TO MAINTAIN VIS SEP WITH CPR Y. THE 2 ACFT PASSED 1.3 MI AND 700' APART. THIS SITUATION COULD EASILY HAVE BEEN PREVENTED. RIC HAS PROCS FOR ARR VS DEP TFC. ARRS ARE USUALLY KEPT AT 4000' ON DOWNWIND TO ALLOW DEPS TO PASS BENEATH AT 3000'. DSNDING ACR X WAS MY FIRST MISTAKE, SHOWING POOR JUDGEMENT. INACTION WAS THE SECTION MISTAKE. COORDINATING WITH THE TWR TO ASSIGN CPR Y A DIFFERENT HDG AFTER DSNDING ACR X WOULD HAVE PREVENTED THIS SITUATION ALSO. MY LAST MISTAKE WAS NOT INSTRUCTING ACR X TO 'MAINTAIN VIS SEP.' WHEN ACR X RPTED CPR Y, IT'S UNSURE WHETHER STANDARD SEP WAS LOST. HOWEVER, W/O THE ABOVE INSTRUCTIONS, VIS SEP IS NOT CONSIDERED TO BE IN EXISTENCE. THUS AS ACR X PASSED BEHIND CPR Y VISUALLY, THEIR TARGETS CAME WITHIN 1.3 MI AND 700', LESS THAN STANDARD RADAR SEP.

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.