Air carrier flight crew reported a RA due to traffic during approach. Crew climbed; TCAS aural message of clear of conflict was given and crew continued approach with uneventful landing.
Synopsis
Air carrier flight crew reported a RA due to traffic during approach. Crew climbed; TCAS aural message of clear of conflict was given and crew continued approach with uneventful landing.
Narrative
I was the FO on Aircraft X ZZZ-DFW. I was the Pilot Flying (PF) on this particular leg. During the approach phase into DFW; we were in a near-midair with a General Aviation (GA) aircraft. We were in communication with Lonestar Approach for RWY 18R. Approximately 20 miles from DFW; we were cleared to descend from 4000' to 3000' and for the ILS 18R. It was hazy and we were not able to see the airport but we were in VMC as we could see at least 5 miles around the aircraft. After accepting the clearance; I initiated the descent to 3000' and set the AP (Autopilot) to track the localizer for 18R. The aircraft captured and tracked the localizer just before leveling off at 3000'. At approximately 15 miles from DFW; the TCAS issued a TA for an aircraft just to our left. I could not see the targets relative altitude due to screen clutter on my ND (Navigation Display). I immediately started looking outside in the direction of the TA aircraft. I was able to visually acquire the TA aircraft; a GA aircraft; moving from our left to right; crossing our track at or slightly below our altitude. The controller then transmitted a Traffic Alert to us of the aircraft being a mile in front of us at roughly the same altitude. At about the same time; the TA became an RA with an initial action to DESCEND". I immediately disconnected the auto pilot and initially started a descent. As I still had visual contact of the GA aircraft; I noticed that the aircraft was lower than us and looked as if it was descending. I then decided to climb as that would be the safer option to avoid the traffic. The TCAS then commanded a reversal to "CLIMB; CLIMB NOW". I was still maintaining visual contact with the traffic as we got the "CLEAR OF CONFLICT" from TCAS. The GA aircraft continued on its path to the west. My maneuver took us approximately 200' above our assigned altitude. I was able to re-establish the aircraft onto the localizer and maintain 3000'. After stabilizing the aircraft; we inquired with the controller about the aircraft. We were informed that the GA aircraft was inside the Bravo airspace but was not in contact with them. We were able to perform the rest of the approach stable and without incident. The remainder of the flight to the gate was uneventful and completed as scheduled. Cause: GA pilot's knowledge of Bravo airspace and regulations governing its use. Recommend more education at local airports about flying near and in Bravo airspace."
Second reporter narrative
While on approach to ILS 18R we experienced an RA from GA Traffic. Weather was a thin overcast layer around 3000. We couldn't see the ground but could see approximately 5 miles. We were cleared by Lonestar approach from 4 to 3 thousand and cleared for ILS 18R. We captured the localizer and were tracking inbound and about to level off at 3 thousand when a TA advisory appeared on our TCAS. I zoomed my ND (Navigation Display) in to see it and the FO who was PF visually acquired it. Lonestar gave a traffic alert for the traffic at the same time we received an RA to descend. I (PM) notified ATC and the FO began to initiate the descent when we noticed the GA traffic was below and also started a descent. The FO began to reverse the response to avoid the aircraft since we could visually see we needed to climb when the RA also reversed to a climb. We climbed about 200 ft by time we cleared the conflict. We were still outside LEGRE and in a safe position to continue the approach after both pilots confirmed they were in the green." The rest of the approach was normal and uneventful.Cause: Lonestar did confirm the GA traffic was in class Bravo and appeared to not be talking to them; so they must have been off altitude and possibly not talking to ATC. This was a potentially very hazardous situation if we had not visually seen them. PF did a great job to mitigate the situation."
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.