Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 176; Flight Crew Total 21500; Flight Crew Type 447
Communication Breakdown; Confusion; Distraction
No Specific Anomaly Occurred All Types
Flight Crew Requested ATC Assistance / Clarification
Procedure; Chart Or Publication; Manuals
I am submitting this report because there are similar sounding fixes on the RIKKK4 RNAV departure in Denver. Two fairly similar sounding waypoints on the same departure. There was no course or heading deviation; but we came close due to confusion over a hear-back issue over our initial ATC clearance which was to proceed direct RIKKK. On Departure off of Runway 25; we were expecting the clearance: Runway 25 RNAV MUGBE clear for takeoff; but instead we were given 'on departure fly heading 350 Runway 25 cleared for takeoff. We departed and flew the assigned heading. After several minutes; we were cleared direct to RIKKK as filed. I read back; cleared direct RIKKK; and then looked down at my FMC as I was the Pilot Monitoring and on the bottom of page 1 of my legs page in the FMC I saw the waypoint 'RINKR.' I assumed that was the fix ATC wanted me to fly to thinking that I must have misunderstood the pronunciation of the waypoint ATC wanted us to fly to. As I began to select RINKR; my relief First Officer questioned me and asked if it was RIKKK or RINKR? I Confirmed with ATC and knew it was RIKKK. We selected direct RIKKK and proceeded on course as filed. At no time did we ever turn towards or execute direct RINKR; but very easily could have made this mistake. Please share with ATC for their general awareness that the naming of these two waypoints are too similar. I hope that these fixes may get an updated name sometime in the future to prevent an unnecessary hear back human factors navigational error.
Air carrier Captain reported a DEN RNAV departure with similar sounding fix names RIKKK and RINKR caused confusion.