Air carrier flight crew reported being on final to a class bravo airport and having to go-around due...

Attributes
ACN	1752942
Time
Date	202007
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft High Wing 1 Eng Fixed Gear
Flight Phase	Cruise
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Events
Anomaly	Conflict Airborne Conflict Inflight Event / Encounter Unstabilized Approach

Narrative:

On final approach for xxr into ZZZ; tower advised of traffic off our left. The traffic could not be visually identified. The traffic appeared to be operating in class B airspace but was not on frequency with tower. As we descended on short final we received two traffic advisories. At approximately 800 feet AGL we received a resolution advisory instructing us to climb. The captain was PF and I was pm. The captain initiated a climb to resolve the conflict. After the climb was initiated a stabilized approach to a landing in the touchdown zone was no longer assured. At that point the safest course of action was to execute a missed approach and the captain proceeded to do so. We executed the missed in compliance with ATC instruction and landed uneventfully on the next attempt.lately I have noticed an increase in small single engine GA aircraft doing landings and pattern work at ZZZ and transiting the class B airspace. With the drastic decrease in fuel prices and lower 121 traffic volume in and around ZZZ it seems there has been a corresponding increase in small aircraft.

Original NASA ASRS Text

Title: Air carrier flight crew reported being on final to a Class Bravo airport and having to go-around due to a small aircraft that was not talking to Tower; which caused the airborne conflict.

Narrative: On final approach for XXR into ZZZ; Tower advised of traffic off our left. The traffic could not be visually identified. The traffic appeared to be operating in Class B airspace but was not on frequency with Tower. As we descended on short final we received two traffic advisories. At approximately 800 feet AGL we received a resolution advisory instructing us to climb. The Captain was PF and I was PM. The Captain initiated a climb to resolve the conflict. After the climb was initiated a stabilized approach to a landing in the touchdown zone was no longer assured. At that point the safest course of action was to execute a missed approach and the Captain proceeded to do so. We executed the missed in compliance with ATC instruction and landed uneventfully on the next attempt.Lately I have noticed an increase in small single engine GA aircraft doing landings and pattern work at ZZZ and transiting the Class B airspace. With the drastic decrease in fuel prices and lower 121 traffic volume in and around ZZZ it seems there has been a corresponding increase in small aircraft.

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.

Air carrier flight crew reported being on final to a class bravo airport and having to go-around due to a small aircraft that was not talking to tower; which caused the airborne conflict.