Narrative:

I was working the local control position at lga. On frequency was air carrier X, a B757 on a 6 mi final to runway 22. Another target, being worked by new york TRACON, flew directly underneath X, which I was working. The new york TRACON controller ran his traffic, which turned out to be a light twin, right under my traffic, in my airspace. He did 'point out' the traffic, but not to me. Our radar position controller received the 'pointout,' but neglected to inform me. I never issued a TA because at the time I noticed the target, it was well outside my airspace. I was working several aircraft at the time, and when I went back to X to clear him to land, I noticed the conflicting traffic directly under him. The pilot of X asked about the traffic that went under him. He saw it on TCASII as well as visually. He did receive an RA on TCASII, but since he had the target visually, he continued the approach. I advised the pilot new york TRACON was working the traffic and gave him the facility phone number to speak with an area supervisor. Several factors involved made this incident potentially dangerous. 1) new york TRACON controller running traffic within someone else's airspace. 2) pointout information never getting to the pertinent controller. 3) TA information not issued to the pilot. At this time, no further action is being taken reference this incident.

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Original NASA ASRS Text

Title: ACR X HAD POSSIBLE LTSS FROM VFR ACFT IN CLASS B AIRSPACE. POSSIBLE SYS ERROR.

Narrative: I WAS WORKING THE LCL CTL POS AT LGA. ON FREQ WAS ACR X, A B757 ON A 6 MI FINAL TO RWY 22. ANOTHER TARGET, BEING WORKED BY NEW YORK TRACON, FLEW DIRECTLY UNDERNEATH X, WHICH I WAS WORKING. THE NEW YORK TRACON CTLR RAN HIS TFC, WHICH TURNED OUT TO BE A LIGHT TWIN, RIGHT UNDER MY TFC, IN MY AIRSPACE. HE DID 'POINT OUT' THE TFC, BUT NOT TO ME. OUR RADAR POS CTLR RECEIVED THE 'POINTOUT,' BUT NEGLECTED TO INFORM ME. I NEVER ISSUED A TA BECAUSE AT THE TIME I NOTICED THE TARGET, IT WAS WELL OUTSIDE MY AIRSPACE. I WAS WORKING SEVERAL ACFT AT THE TIME, AND WHEN I WENT BACK TO X TO CLR HIM TO LAND, I NOTICED THE CONFLICTING TFC DIRECTLY UNDER HIM. THE PLT OF X ASKED ABOUT THE TFC THAT WENT UNDER HIM. HE SAW IT ON TCASII AS WELL AS VISUALLY. HE DID RECEIVE AN RA ON TCASII, BUT SINCE HE HAD THE TARGET VISUALLY, HE CONTINUED THE APCH. I ADVISED THE PLT NEW YORK TRACON WAS WORKING THE TFC AND GAVE HIM THE FACILITY PHONE NUMBER TO SPEAK WITH AN AREA SUPVR. SEVERAL FACTORS INVOLVED MADE THIS INCIDENT POTENTIALLY DANGEROUS. 1) NEW YORK TRACON CTLR RUNNING TFC WITHIN SOMEONE ELSE'S AIRSPACE. 2) POINTOUT INFO NEVER GETTING TO THE PERTINENT CTLR. 3) TA INFO NOT ISSUED TO THE PLT. AT THIS TIME, NO FURTHER ACTION IS BEING TAKEN REF THIS INCIDENT.

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.