Date: 201907
Local time of day: 1801-2400
Location: DEN.Airport, CO
Flight conditions: VMC
Aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B DEN
ATC / advisory: TRACON D01
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Confusion; Situational Awareness; Communication Breakdown
Second reporter function: First Officer; Pilot Flying
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Detector: Automation Aircraft RA; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Returned To Clearance; Flight Crew Became Reoriented
Contributing factors: Human Factors; Procedure
Primary problem: Procedure

Narrative: DEN arrival VFR day with mod but study winds from the southwest. We briefed almost one hour prior to landing; our plan was the SPAWN WAHUU2 16R arrival. The First Officer had been flying into DEN several times lately and had experienced [Runway] 16R a majority of the time. She did an excellent job briefing and going over the descent profile and checking the FMC. TOD was about 35 min prior to landing so we had a good 25 mins after brief of drone time. Somewhere after SLMON; we were given direct to WAHUU at 9;000 ft. Then about mid-point; and still a very controlled and quiet day we were given a heading off the arrival towards the southwest (dogleg to final) almost pointed right at NEWLN. First received a descent to 8;000 ft. then 7;000 ft. right at the Class B border where the floor drops to 7;000 ft. At this point I don't remember but it's possible the Controller said expect [Runway] 16L but I don't remember him saying it. When we were at 7000 ft. and slowing to 210; the Controller cleared us the visual. So this much I do remember clearly; he cleared us the visual without asking if we had the airport in sight or naming a RWY. We were slowing. The First Officer was doing a nice job thinking ahead and I heard the Controller voice with a quick cadence; so I felt he was a little busy so I accepted the clearance; I extended JETSN and the First Officer continued to slow and configure. Everything was under control until about that point. The Controller came back and asked if we had the airport in sight which was a little strange since we already accepted the visual clearance but I acknowledged we did. He then asked us to maintain 180kts to LUWEE go to Tower on 135.3. That's when my brain went into overload because I didn't know where LUWEE was. About the time; we realized we were cleared for [Runway] 16L we were overshooting final heading for [Runway] 16R. The First Officer turned to come back on final for [Runway] 16L when I saw what I thought was an Airbus above and next to us. Mind you; we were in a 20 degree left turn and I had visual on the aircraft looking outside the First Officer R Aft window. At that point; I asked her for 30 degree of turn which she complied. Somewhere in there; we received a TCAS RA Descend which she complied; about then Tower came back and asked if we had the aircraft in sight which I did and acknowledged. I felt we never got any closer than an SFO approach to 28 but were weren't expecting to be there. But factoring in the TCAS we must have been close or with an initial vector underneath the Airbus on [Runway] 16R for the TCAS to issue a RA. The First Officer continued to configure and slow while I programmed the ILS and FMC. She was lined up on the cleared runway now; somewhere before seeing the other aircraft I did ask tower to confirm [Runway] 16L; which they did. I feel somewhere on arrival the controller might of said expect 16L but it never hit me; but again I'm not sure. My mistake was not reviewing [Runway] 16L and I'm still confused as to why I didn't expect it coming in from the east. By 1;000 ft. I had the ILS and FMC programmed and the First Officer had the aircraft under control and configuring the aircraft while I sorted out runway alignment and then heads down to tune the ILS and FMC. I briefly thought about a go around but felt it would have added a layer of confusion when by 700 ft. we were back in normal ops. After landing; we got a call from the flight attendants about a faint smell of burning plastic in the cabin. I asked if it was fuel smell or smoke in the cabin which I received a negative reply. At the time were stopped but elected to continue to the gate. We had two pilots in the back and both stopped by to say goodbye only one could smell the odor and gave the same description of almost like a plastic burning. I really thought the phone call was going to ask if we were doing a formation approach. Expectation bias and not reviewing appropriate approaches are lessened learned; I'vealways thought I was cognizant of expectation bias but missed it that day. We talked/briefed at length about Class B airspace and the pitfalls of DEN and high descent rates but missed other threats like runway configuration and who was getting what runway in front of us.


Second narrative: [Report narrative contained no additional information.]


Synopsis: Air carrier flight crew reported clearance confusion resulting in overshooting final and airborne conflict.