Narrative:

Aircraft #1 inbound to bis on the ILS runway 13 approach. Aircraft #1 is VFR, however, is on a VFR practice approach so is protected like an IFR. Aircraft #2 departs runway 13 at bis with a left turn on course to the northwest practice area. I see that traffic needs to be issued to the 2 aircraft so I ship aircraft #2 to departure for his radar advisories. I shipped aircraft #2 because I determined the conflict was going to take place outside of my airspace (outside 5 mi). I did not know, however, that the approach controller had already shipped aircraft #1 to my frequency. Either aircraft #1 did not check on or I did not hear him check on. I assumed that the approach/departure controller was issuing traffic to both aircraft. The next transmission I hear is aircraft #1 asking why he was not told about aircraft #2 that just flew over him. I felt horrible. All I could tell him was that I didn't think he was on my frequency and apologize for the mistake. The 2 radar targets were right on top of each other and I am guessing that they were less than 300 ft apart vertically. Causes: me assuming that the other controller was working it out. I should have made sure. Also, the other controller was training so may not have seen the conflict was going to take place in his airspace. He should have kept aircraft #1 and issued traffic, but because he didn't, I should have made sure (don't assume) traffic was exchanged between both aircraft. Another pair of eyes in the cabin attendant would have been wonderful.

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Original NASA ASRS Text

Title: A VFR PA28 DEP CONFLICTS WITH AN INBOUND PA34 ON A PRACTICE IFR APCH APPROX 5 MI FROM THE ARPT. THE OUTBOUND ACFT WAS CHANGED TO APCH CTL FREQ AND THE INBOUND PA34 WAS JUST SWITCHED TO TWR FREQ. NO TA'S WERE ISSUED.

Narrative: ACFT #1 INBOUND TO BIS ON THE ILS RWY 13 APCH. ACFT #1 IS VFR, HOWEVER, IS ON A VFR PRACTICE APCH SO IS PROTECTED LIKE AN IFR. ACFT #2 DEPARTS RWY 13 AT BIS WITH A L TURN ON COURSE TO THE NW PRACTICE AREA. I SEE THAT TFC NEEDS TO BE ISSUED TO THE 2 ACFT SO I SHIP ACFT #2 TO DEP FOR HIS RADAR ADVISORIES. I SHIPPED ACFT #2 BECAUSE I DETERMINED THE CONFLICT WAS GOING TO TAKE PLACE OUTSIDE OF MY AIRSPACE (OUTSIDE 5 MI). I DID NOT KNOW, HOWEVER, THAT THE APCH CTLR HAD ALREADY SHIPPED ACFT #1 TO MY FREQ. EITHER ACFT #1 DID NOT CHK ON OR I DID NOT HEAR HIM CHK ON. I ASSUMED THAT THE APCH/DEP CTLR WAS ISSUING TFC TO BOTH ACFT. THE NEXT XMISSION I HEAR IS ACFT #1 ASKING WHY HE WAS NOT TOLD ABOUT ACFT #2 THAT JUST FLEW OVER HIM. I FELT HORRIBLE. ALL I COULD TELL HIM WAS THAT I DIDN'T THINK HE WAS ON MY FREQ AND APOLOGIZE FOR THE MISTAKE. THE 2 RADAR TARGETS WERE RIGHT ON TOP OF EACH OTHER AND I AM GUESSING THAT THEY WERE LESS THAN 300 FT APART VERTLY. CAUSES: ME ASSUMING THAT THE OTHER CTLR WAS WORKING IT OUT. I SHOULD HAVE MADE SURE. ALSO, THE OTHER CTLR WAS TRAINING SO MAY NOT HAVE SEEN THE CONFLICT WAS GOING TO TAKE PLACE IN HIS AIRSPACE. HE SHOULD HAVE KEPT ACFT #1 AND ISSUED TFC, BUT BECAUSE HE DIDN'T, I SHOULD HAVE MADE SURE (DON'T ASSUME) TFC WAS EXCHANGED BTWN BOTH ACFT. ANOTHER PAIR OF EYES IN THE CAB WOULD HAVE BEEN WONDERFUL.

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.