Air carrier flight crew conducting a visual approach reported a NMAC with a helicopter that climbed to their altitude.
Synopsis
Air carrier flight crew conducting a visual approach reported a NMAC with a helicopter that climbed to their altitude.
Narrative
We were inbound direct to ZZZ and talking to Approach at 5000ft MSL when we were advised of an air ambulance helicopter that had just departed ZZZ headed westbound. I advised that we were looking for traffic and had the airport in sight. ATC cleared us for the visual to XXR. We began a descent to 2400ft MSL and turned to a more southerly heading to enter an extended base leg. Shortly after that; ATC gave us another position report on the helicopter and told us to maintain 3000 feet until clear of the traffic. I read back the instruction and advised that I still did not have the traffic. The FO and I were both checking for the traffic visually using the the position we could see for the helicopter on our iPads and on the TCAS. It became clear that the helicopter and us were on a collision course. We assumed that the helicopter had been told to maintain a lower altitude. The TCAS showed that the helicopter continued climbing above 2000 feet. I saw it showing 900 feet below; then 700 feet below and could not find it visually. When I looked at the TCAS again; it was 400 feet below our altitude. We immediately began a climb to avoid the traffic. By the time we started the climb; the TCAS gave us a traffic alert and showed the helicopter only 200 to 300 feet below our altitude. I looked out my window (left side of the plane) and finally spotted the traffic as it was about to pass under us. We stopped the climb and I advised approach of what we had to do. He said ok and told us to turn base inside of ZZZZZ and to contact the tower. We proceeded with our Visual Approach from that point.
Second reporter narrative
As pilot flying coming into the Class B of ZZZ1 we were assigned 7000 feet to cross ZZZZZ by Center. As we continued our descent we were handed over to Approach; the controller directed us to expect the visual for XXR and directed us direct to ZZZ sometime after he cleared us down to 5000. Within 10 or so miles we reported the field in sight and he cleared us for the approach. Selecting the FAF altitude of 2400 and having programmed the GPS for ZZZZZ I started the descent. Roughly around this time the controller made a call for a helicopter traffic heading westbound toward us. PIC replied searching for traffic. As I continued the decent to 2400 the controller asked for us to stop our descent at 3000. I set the altitude to 3000 and we leveled off around 7 miles or so from ZZZ. Approximately a few seconds later I could see on the TCAS the traffic and saw that it was climbing towards us. Captain said he then had did not have traffic in sight and proceeded to tell me to climb. I added power to the notches careful not to over torque and disconnected the Autopilot to climb above the 3000 it was set at. During this the TCAS called TRAFFIC. Around 3400 I leveled off and saw that the traffic was -400 below. The Captain called ATC stating we had to climb to avoid traffic that was still climbing into our path. During the entire event being on the right side of the aircraft I never had the helicopter in sight other than on TCAS. After the traffic was cleared of us ATC directed us to turn base inside TOD (Top of Descent) ZZZZZ due to a Caravan traffic that was inbound to ZZZ as well.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.