Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 20; Flight Crew Total 10000; Flight Crew Type 3000
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Human Factors; Procedure
Flight plan was filed as ... RZC LBL KD45U KD48U MVA HNW… Clearance was given by Clearance Delivery as 'Cleared as Filed' and there were no route clearance modifications given by ATC. On the western edge of Kansas City ATC; we were asked what point we were navigating to. As the pilot not flying I selected the Legs page of the FMC and responded that we were navigating to 'KD54U.' The Controller asked me to confirm the point; I again referred to the FMC Legs page and replied 'KD54U.' At this point the First Officer (pilot flying) was referring to the flight plan and recognized we had transposed the flight planned point 'KD45U' to 'KD54U.' To avoid any chance of continued confusion the Controller then cleared us direct to 'KD48Q.' Referring to the High Chart we noticed that not only were the NRS points 'KD54U' and 'KD45U' similar in name; they were also very close in distance. Since the implementation of NRS; I have been aware of the possibility of entry errors and in the beginning of the program developed and used successfully a personal flight plan cross check that discovered a couple of entry errors before leaving the blocks. This personal flight plan cross check included the careful reading of the NRS points on the flight plan and the careful cross check of them in the FMC Route page; and the comparison of the flight plan distance with the FMC Progress Page distance to destination. Unfortunately; due to the close proximity of the geographical points; a significant discrepancy was not readily evident. This combined with the similar nomenclature of the two involved NRS points caused to two experienced crew members to experience a navigation error. After careful thought; the only solution I can identify to keep me from experiencing a similar error is the continued careful use of my aforementioned technique; and to additionally include the FMC/MFP verification procedures used in over-water cockpit preparation procedures. By checking the flight planned course and distance against the FMC computed course and distance for the all of the points from one waypoint prior to the first flight planned NRS point to one waypoint after the last flight planned NRS; I hope to trap any errors and never experience this again.
As both these points are abeam each other at relatively close range (the cumulative distance is almost exactly the same with either point loaded); both pilots' review of the flight plan did not catch this error. To prevent similar navigation problems with these RNAV points; it might be helpful to adopt a more random naming protocol; so that a typo would result in a 'point not in database' error message; rather than loading a close; but different; point. Of course; as always; stringent reviews of the loaded flight plan; and expected turn heading updates at each waypoint in flight; remain the ultimate defenses from 'fat fingers.'
A crew transposed NRS fix numbers so that when ATC saw the start of a track deviation; it was determined the aircraft was flying to KK54U instead of KK45U.