Air carrier flight crew reported a NMAC during approach with a helicopter that resulted in a TCAS RA response to avoid collision.
Synopsis
Air carrier flight crew reported a NMAC during approach with a helicopter that resulted in a TCAS RA response to avoid collision.
Narrative
As we approached ERI Airport; approach control cleared us for a visual approach to runway 24. During our downwind to base turn; we were instructed to contact the tower; which subsequently cleared us to land on runway 24. Prior to initiating our base-to-final turn; our TCAS system provided a traffic advisory; indicating that we should monitor our vertical speed.I immediately began scanning outside for traffic approximately 100 feet above us. Following this; TCAS prompted us to descend; and the captain complied with the descent request while I visually searched for the traffic. Upon locating the helicopter; I confirmed it was 100 feet above us. We promptly communicated our response to the tower regarding the traffic resolution.We successfully continued our approach and landed without incident. The air traffic control (ATC) controller informed us that the helicopter had us in sight; but did not provide us with prior notification regarding the traffic. Our first indication of the helicopter's presence came solely through the TCAS system. Once on the ground; I expressed my appreciation to the captain for his composure and prompt action during the situation while I was focused on identifying the traffic. We were concerned that ATC had not alerted us to the helicopter; as lessons from the January 2025 incident in Washington; DC; may not have been fully integrated into current operational protocols.Effective communication between Air Traffic Control (ATC) and both aircraft that are on a potential collision course under visual flight conditions is essential for ensuring safety and coordination in the airspace.It is essential to ensure that the pilot monitoring displays the TCAS screen when preparing for a visual approach.
Second reporter narrative
Coming into ERI; we were cleared for the visual approach to runway 24. We started in a left downwind at 3200 feet; using guidance from the ILS 24 approach plate. We turned a left base a couple of miles outside of the final approach fix; staying at 3200. After wings level in the base; we received a traffic alert from the tcas indicating a target about 1 o clock ahead and 100 ft above us. A few seconds later; we heard a 'monitor vertical speed' in which I disconnected the autopilot and prepared for a resolution advisory. A few seconds after that we got a 'descend descend' RA in which I followed until we got a 'clear of conflict' message. The FO then told tower we responded to an RA. The tower controller then told us that the helicopter did have us in sight. We were never made aware that a helicopter was ahead of us on the approach path. The rest of the flight was uneventful.ATC failed to alert us of a helicopter in the vicinity of the approach path.ATC needs to announce traffic that is in the approach corridor of the airport.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.