B737 Undifferentiated or Other Model
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Situational Awareness
ATC Issue All Types; Conflict NMAC; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action
Human Factors; Procedure
Had an RA and turned and descended 400 ft. to avoided traffic. Controller sent us on a heading and altitude to fly close to a light twin. [We] banked hard to the left and lost 400 ft.
B737 Captain reported a NMAC with a light twin during climb.