B737 flight crew reported two TCAS RA's while on approach to den that resulted in a missed approach.

Attributes
ACN	1582148
Time
Date	201810
Local Time Of Day	0601-1200
Place
Locale Reference	DEN.Airport
State Reference	CO
Environment
Light	Dawn
Aircraft 1
Make Model Name	B737 Next Generation Undifferentiated
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Visual Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Medium Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Conflict Airborne Conflict Inflight Event / Encounter CFTT / CFIT Inflight Event / Encounter Unstabilized Approach

Narrative:

Coming into den 16L for the visual on an extremely busy morning; we were cleared for the visual to 16L behind [another aircraft]; three to five miles ahead of us and were told to hold 160 KIAS to the FAF. On approximately 12-mile final; we heard ATC call out traffic behind us converging towards the parallel 16R. Shortly after; we received our first RA. The first officer (first officer) reacted appropriately and we were quickly clear of conflict. We informed approach and let them know we were continuing. Again; at around a seven or eight mile final; we received an RA to descend. Following the RA we got fast (approximately 190 KIAS). We also descended to approximately 7600 feet before the RA went away. At that point we began a very shallow non-standard go-around because we were partially configured; closing on the traffic in front of us; and concerned much of a climb would put us into conflict with the traffic behind us again. Frankly; we were threading a needle because ATC had high radio congestion; there was traffic in front of us; traffic to our right; and traffic on approach to our left. While reacting the second time; we informed ATC and let them know we would be going around. ATC gave us a warning that we were too low; and switched us to tower for go-around instructions. Once on tower we began transitioning to a normal go-around and returned to land uneventfully.

Original NASA ASRS Text

Title: B737 flight crew reported two TCAS RA's while on approach to DEN that resulted in a missed approach.

Narrative: Coming into DEN 16L for the visual on an extremely busy morning; we were cleared for the visual to 16L behind [another aircraft]; three to five miles ahead of us and were told to hold 160 KIAS to the FAF. On approximately 12-mile final; we heard ATC call out traffic behind us converging towards the parallel 16R. Shortly after; we received our first RA. The First Officer (FO) reacted appropriately and we were quickly Clear of Conflict. We informed Approach and let them know we were continuing. Again; at around a seven or eight mile final; we received an RA to descend. Following the RA we got fast (approximately 190 KIAS). We also descended to approximately 7600 feet before the RA went away. At that point we began a very shallow non-standard go-around because we were partially configured; closing on the traffic in front of us; and concerned much of a climb would put us into conflict with the traffic behind us again. Frankly; we were threading a needle because ATC had high radio congestion; there was traffic in front of us; traffic to our right; and traffic on approach to our left. While reacting the second time; we informed ATC and let them know we would be going around. ATC gave us a warning that we were too low; and switched us to Tower for go-around instructions. Once on Tower we began transitioning to a normal go-around and returned to land uneventfully.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.