Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 92.3; Flight Crew Total 7143.83; Flight Crew Type 7143.83
Situational Awareness
Conflict NMAC; Deviation / Discrepancy - Procedural FAR
Air Traffic Control Issued Advisory / Alert; Flight Crew Took Evasive Action
Airspace Structure; Human Factors
On approach to IAH; just prior to FESTA on the Runway 27 ILS being flown in VFR conditions;  we were notified by IAH Approach Control of VFR / no com traffic as we were receiving a TA and almost immediately an RA for that traffic at 400 feet below our path.  As the controller was handing us off to the Tower; I advised him that we were responding to an RA.  Another voice acknowledged this; and we were then switched to IAH Tower.  The visual approach continued without further incident.
Air carrier Captain reported an NMAC during initial approach to IAH airport when an aircraft not in communication with ATC flew below them.