B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 120; Flight Crew Type 120
Confusion; Distraction; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
Aircraft; Procedure; Human Factors
On the WRAPS 5 Arrival into SMF when the airport was switched from north flow to south flow. The First Officer changed the arrival with a south flow and 16R. I checked the route and he accepted it. During the arrival; ATC asked if we were going direct to the airport. When I looked down; I noticed the next point was Runway 16R. I told ATC that our route had dropped out of the box and he stated; 'No problem; fly heading 310 for vectors to 16R. The remainder of the flight was uneventful. I am not sure when the navigation route dropped out of the system. The only change I can think to make is increased vigilance of where the LNAV is directing the aircraft; especially during busy portions of the flight.
[Report narrative contained no additional information.]
A B737-NG crew flying the SMF WRAPS 5 changed the arrival to a south landing on Runway 16R and after executing the FMS change; all route data except the runway dropped out.