Local controller described near midair collision event when an air carrier on final declared same wi...

Narrative:

An emb-175 checked in with me on about a 10 mile final and I cleared him to land xxl. At the time it appeared that there was a VFR near the marker moving north. I then went on to talk to a [another airliner] and a few helicopters. North radar (nr) called up and said I did not issue the emb-175 that traffic. I immediately issued the traffic; still thinking he was northbound. The emb-175 then started telling me how the aircraft had turned towards him and he had to take actions to miss hitting the aircraft. I called down to the TRACON and was informed that the piper aztec had the emb-175 in sight and was maintaining visual with him. I advised the emb-175 pilot of this and he said he was going to file a near midair collision. I informed the supervisor of his actions. I then went down to the TRACON and was told we did everything right; no rules broken. Have picture taking aircraft remove themselves from final.

Original NASA ASRS Text

Title: Local Controller described NMAC event when an air carrier on final declared same with a helicopter operating near the final that was maintaining visual separation with the air carrier.

Narrative: An EMB-175 checked in with me on about a 10 mile final and I cleared him to land XXL. At the time it appeared that there was a VFR near the marker moving north. I then went on to talk to a [another airliner] and a few helicopters. North RADAR (NR) called up and said I did not issue the EMB-175 that traffic. I immediately issued the traffic; still thinking he was northbound. The EMB-175 then started telling me how the aircraft had turned towards him and he had to take actions to miss hitting the aircraft. I called down to the TRACON and was informed that the Piper Aztec had the EMB-175 in sight and was maintaining visual with him. I advised the EMB-175 pilot of this and he said he was going to file a NMAC. I informed the Supervisor of his actions. I then went down to the TRACON and was told we did everything right; no rules broken. Have picture taking aircraft remove themselves from final.

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.

Attributes
ACN	1105728
Time
Date	201207
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	EMB ERJ 170/175 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	PA-23-250 Aztec
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	VFR
Person 1
Function	Local
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict NMAC

Local controller described near midair collision event when an air carrier on final declared same with a helicopter operating near the final that was maintaining visual separation with the air carrier.