Narrative:

Departure strip printed and I retrieved for an A320. Pilot checked in climbing to 3;000 ft on runway heading. I observed the primary target off the departure end; established radar contact with the aircraft; and instructed it to climb to 15;000 ft and turn left heading 360. I meant to ask the pilot to make sure transponder was on; but did not. I got busy with other departures and arrivals and forgot about the primary target aircraft. Pilot called back about ten minutes later to verify he was supposed to still be on my frequency. I expanded the radar scope range and asked the pilot to turn the transponder on; the A320 tagged up about 30 miles beyond approach airspace boundary; level at 15;000 ft. I called center to perform a late hand off; center accepted the hand off and I switched the aircraft. Recommendation; be more alert.

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Original NASA ASRS Text

Title: TRACON Controller described an airspace incursion event into an adjacent Center sector when departure traffic; without a transponder; went unnoticed by the reporter after initially being RADAR identified as a primary target off the runway.

Narrative: Departure strip printed and I retrieved for an A320. Pilot checked in climbing to 3;000 FT on runway heading. I observed the primary target off the departure end; established RADAR contact with the aircraft; and instructed it to climb to 15;000 FT and turn left heading 360. I meant to ask the pilot to make sure transponder was on; but did not. I got busy with other departures and arrivals and forgot about the primary target aircraft. Pilot called back about ten minutes later to verify he was supposed to still be on my frequency. I expanded the RADAR scope range and asked the pilot to turn the transponder on; the A320 tagged up about 30 miles beyond Approach airspace boundary; level at 15;000 FT. I called Center to perform a late hand off; Center accepted the hand off and I switched the aircraft. Recommendation; be more alert.

Data retrieved from NASA's ASRS site as of July 2013 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.