CTLR ALLOWED ACR SMT TO GET AWAY WHILE ON VECTOR. SMT ENTERED ADJACENT CTLR'S AIRSPACE AND CONFLICTED WITH ANOTHER SMT ON VECTOR FINAL APCH COURSE.

Narrative

I ASSUMED THE NOBBI APCH (HPN ARR) POS. AT THE TIME THERE WAS AN ATCS DEVELOPMENTAL CTLR TRNING ON THE POS. TFC WAS LIGHT; MAYBE 3-4 ACFT AND A DEP RELEASED OFF DANBURY (DXR). I WAS BRIEFED AS TO THE TFC SITUATION. SMT X WAS 6-7 MI SW OF HPN ON A LEFT DOWNWIND TO RWY 34. THE DXR ACFT DEPARTS AND CHKS IN LEVEL AT 2000'. DXR DEP RPTS LEVEL AT 2000' AND IS RADAR IDENTED. SECS LATER THE ACFT REQUEST TO RETURN TO DXR DUE TO A SICK PAX. THE DEV IS NOT SURE AS TO WHAT TO DO; SO I TELL HIM. HE ISSUES INSTRUCTIONS FOR THE ACFT'S RETURN TO DXR. HOWEVER; WX IS REQUIRED TO BE ISSUED FOR THIS NON RADAR APCH TO DXR. AS THE DEV IS ISSUING THE WX; I NOTICE THE POS OF SMT X (AT SAME TIME ANOTHER CTLR ALERTS ME OF SAME). SMT X IS APPROX 19 NM SE OF HPN; HDG 130 DEGS. I ISSUE SMT X A RIGHT TURN 020 DEGS. I ALSO COORDINATE WITH THE CTLR WHO'S AIRSPACE THE ACFT IS IN (JFK ERICK APCH). I ISSUE TFC 10 O'CLOCK AND ASK SMT X FOR HARD RIGHT TURN 020 DEGS. SMT X ADVISED HE DOES NOT SEE TFC. THE TFC WAS SMT Y ON VECTOR TO REPUBLIC ARPT RWY 14. SMT Y WAS APPROX 5 NM N OF FRG RWY 14 OM WHEN INCIDENT OCCURRED. SMT Y WAS RPTED 5 NM NE OF FRG RWY 14 LEVEL AT 2000'. SMT Y WAS ISSUED RIGHT TURN HDG 310 DEGS. SMT Y WAS ISSUED TFC 1 O'CLOCK; 2 MI (SMT X). THEN SMT Y WAS ISSUED A LEFT TURN HDG 220 DEGS. AT THIS TIME SEP WAS APPROX 100' AND 1/2 MI. NEITHER ACFT SAW THE OTHER. THE MAIN FACTOR CONTRIBUTING TO THIS INCIDENT WAS MY (AND THE DEV'S) BEING DISTRACTED BY THE DXR DEP. I ALSO BELIEVE I SHOULD HAVE ENSURED; AS I ASSUMED THE POS; THAT THOSE THINGS THAT NEEDED TO BE DONE IMMEDIATELY OR SOON AFTER WERE ACCOMPLISHED; IE; ENSURING THAT THE DEV TURNED SMT X ON TO THE FINAL AT HPN BEFORE THE ACFT GOT AWAY FROM US. I GUESS YOU COULD SAY IT WAS A MATTER OF INATTN ON MY PART.