Date: 201906
Location: DEN.Airport, CO
Flight conditions: VMC
Aircraft: Commercial Fixed Wing
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 Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Confusion; Communication Breakdown; Situational Awareness
Anomaly: Conflict Airborne Conflict; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Undershoot; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Aircraft RA; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: [We were] on the WAHUU 2 RNAV. Approaching KOKOO on the WAHUU 2 RNAV; ATC cleared us 'Direct KUURT maintain 9000'. Shortly thereafter ATC cleared us 'Intercept RWY 16L LOC. Cleared Visual RWY 16L. Cross KIKME at 8000'. By this time the F/O (First Officer) was hand flying the aircraft so I selected LOC on the FCU. F/O stated that he will remain at 9000' and capture the G/S so as to comply with 8000' at KIKME and remain above the floor of the Class B airspace. Approaching KUURT at 9000' LOC on the FMA was triggered. ATC then stated 'Descend to 8000' NOW'. As the F/O was banking to capture the LOC we received a TCAS RA directing a descent. I noticed on my ND (NAV Director) there was traffic above; behind and to the left of our position but I could not make visual contact. The F/O complied with the RA and I stated to ATC that we were complying with a TCAS RA. I noted that at this time we had flown slightly through our localizer as we attempted to keep a distance laterally from our TCAS traffic that remained above; behind and to our left. As the F/O corrected back to the centerline we received another TCAS RA; shortly followed by 'Clear of Conflict'. The F/O shallowed his descent; captured the G/S and landed uneventfully. As we were taxiing in Ground Control requested that we contact Denver TRACON. Upon completing all our checklists we debriefed the approach and landing to 16L. We discussed the TCAS RA; the F/O response which I stated was done properly; the fact that he acknowledged that he deviated right of the localizer during the TCAS RA maneuver; and the meaning of 'Cleared for the visual approach'. We discussed the fact that I never had visual contact of the intruding aircraft. We also reviewed all the altitudes on the approach chart. I contacted Denver TRACON and ended up speaking with a supervisor. He wanted to discuss this approach to 16L and ensure that all the procedures they are implementing were safe. I put him on speaker phone and had my F/O talk through what he observed as he was the pilot flying the approach. I stated that as the pilot monitoring I never had a visual on the aircraft. [The supervisor] had already listened to the tapes and informed us that our clearance was to cross KUURT at 8000' not KIKME as depicted on the chart. This was so as to facilitate a 1000' separation for a descending aircraft overhead to cross over to land on 16R. Apparently I read back the correct clearance but when we both looked at the approach chart we believed it was 8000' at KIKME and we were cleared for the visual so it all made sense.




Synopsis: Commercial Fixed Wing Captain reported failure to make a crossing restriction on the WAHUU2 RNAV Arrival into DEN following a misunderstanding of the ATC clearance.