An aircraft was in a controller's sector with only a 'limited' data block displayed. The controller ...

Narrative:

Aircraft X was turned on course and climbed. Approaching 5000 feet the pilot asked if his assigned altitude was 5000 feet or 15000 feet. I said 15000 feet and he responded that traffic was descending overhead. I then noticed the target. It was a target with altitude only and no beacon code and it was aircraft Y. I told aircraft X about the target and said I am not talking to that aircraft. Aircraft Y keyed up and said it was him. I clicked on target and noticed it was on the wrong code; got correct code from the flight data printer which is not at the position. I gave aircraft Y the correct code and still could not track up the aircraft. I had to get the supervisor to track up the data block from the coordinator position. The session was quite busy and complex. Previously during same session I had asked for a coordinator and denied VFR flight following to numerous aircraft. Aircraft X noticing the other aircraft visually and or on TCAS and questioning the altitude was the only thing that prevented an error. I'm not sure if I accidentally dropped the aircraft Y data tag or if the tag was never handed off from ARTCC in the first place. I do not recall talking to aircraft X previously; but I was very busy and cannot recall for sure. Final and departure west were both open at the time.

Original NASA ASRS Text

Title: An aircraft was in a Controller's sector with only a 'limited' data block displayed. The Controller did not notice the target or realize the aircraft was on their frequency and flying through their airspace.

Narrative: Aircraft X was turned on course and climbed. Approaching 5000 feet the pilot asked if his assigned altitude was 5000 feet or 15000 feet. I said 15000 feet and he responded that traffic was descending overhead. I then noticed the target. It was a target with altitude only and no beacon code and it was Aircraft Y. I told Aircraft X about the target and said I am not talking to that aircraft. Aircraft Y keyed up and said it was him. I clicked on target and noticed it was on the wrong code; got correct code from the Flight Data Printer which is not at the position. I gave Aircraft Y the correct code and still could not track up the aircraft. I had to get the supervisor to track up the data block from the coordinator position. The session was quite busy and complex. Previously during same session I had asked for a coordinator and denied VFR flight following to numerous aircraft. Aircraft X noticing the other aircraft visually and or on TCAS and questioning the altitude was the only thing that prevented an error. I'm not sure if I accidentally dropped the Aircraft Y data tag or if the tag was never handed off from ARTCC in the first place. I do not recall talking to Aircraft X previously; but I was very busy and cannot recall for sure. Final and departure west were both open at the time.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1324265
Time
Date	201601
Local Time Of Day	1201-1800
Place
Locale Reference	BNA.TRACON
State Reference	TN
Environment
Light	Daylight
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Aircraft 2
Make Model Name	EMB ERJ 135 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Descent
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 2.0
Events
Anomaly	ATC Issue All Types Airspace Violation All Types Conflict Airborne Conflict Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy

An aircraft was in a controller's sector with only a 'limited' data block displayed. The controller did not notice the target or realize the aircraft was on their frequency and flying through their airspace.