B737 first officer reported a track deviation occurred on the RNAV (rnp) Z approach to 35R in den wh...

Narrative:

We had originally planned and briefed the KIPPR5 arrival and the ILS approach to runway 16L into denver. Our arrival was later changed to the ANCHR4. We then set up and briefed this arrival and the ILS to 35R; which was the expected approach based on the latest ATIS. When contacting denver approach; we were assigned the RNAV (rnp) Z to 35R. In the course of flying this approach; we were assigned several non-standard speeds which further increased our workload. Because of this; we did not notice that there was an extraneous vector leg after msims which was a remnant of the ANCHR4. The plan view on our displays showed msims and the radius to fronz; which appeared to be the active course. When passing msims we did not make the turn onto the radius and instead continued straight ahead briefly. We noticed the deviation immediately and were about to contact approach when they called us with vectors to a visual approach; since they had also observed that we were off of the planned course. We were vectored onto final approach for a visual to runway 35R and landed without further incident.

Original NASA ASRS Text

Title: B737 First Officer reported a track deviation occurred on the RNAV (RNP) Z Approach to 35R in DEN when the FMC was programmed improperly following a late clearance change.

Narrative: We had originally planned and briefed the KIPPR5 Arrival and the ILS approach to Runway 16L into Denver. Our arrival was later changed to the ANCHR4. We then set up and briefed this arrival and the ILS to 35R; which was the expected approach based on the latest ATIS. When contacting Denver Approach; we were assigned the RNAV (RNP) Z to 35R. In the course of flying this approach; we were assigned several non-standard speeds which further increased our workload. Because of this; we did not notice that there was an extraneous vector leg after MSIMS which was a remnant of the ANCHR4. The plan view on our displays showed MSIMS and the radius to FRONZ; which appeared to be the active course. When passing MSIMS we did not make the turn onto the radius and instead continued straight ahead briefly. We noticed the deviation immediately and were about to contact Approach when they called us with vectors to a visual approach; since they had also observed that we were off of the planned course. We were vectored onto final approach for a visual to Runway 35R and landed without further incident.

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.

Attributes
ACN	1591740
Time
Date	201811
Local Time Of Day	0601-1200
Place
Locale Reference	DEN.Airport
State Reference	CO
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Route In Use	STAR ANCHR FOUR
Flight Plan	IFR
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Type 259
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy Deviation - Track / Heading All Types

B737 first officer reported a track deviation occurred on the RNAV (rnp) Z approach to 35R in den when the FMC was programmed improperly following a late clearance change.