Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Communication Breakdown
ATC Issue All Types; Conflict NMAC; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Took Evasive Action
Human Factors
After takeoff; leveled off at 5;000 feet per ATC instructions while inside Class B airspace. Got an RA descend; single engine aircraft came within 400 feet of aircraft. Reported RA to ATC. They did not seem concerned.Cause - ATC vectored us within 500 feet of a small airplane.
Air carrier Captain reported an NMAC event after ATC assigned a level off during initial climb after takeoff from MSP.  The flight crew complied with the TCAS RA and notified ATC.