Commercial Fixed Wing
Flight Crew Last 90 Days 220; Flight Crew Total 20000; Flight Crew Type 5000
Situational Awareness; Human-Machine Interface
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors; Aircraft
After loading the route; departure and runway; some subsequent action caused the runway and departure to be removed. We discovered that the runway was missing on taxi and it was reloaded; but we did not see that the departure was missing. LNAV was selected for the departure. We verified the runway and after takeoff a left turn was commanded. That was normal; however; the remainder of the departure was absent and a continued left turn was directed. I quickly determined that I was getting incorrect guidance so reverted to Heading Select. However; in the transition period we turned beyond the prescribed departure course before making the correction.
Air Carrier Captain discovers during taxi that the departure runway has been removed from the FMC and reloads it. After takeoff LNAV is engaged and a turn initiated; which the Captain quickly determines is not correct. The departure procedure had also been removed from the FMC by what ever action had removed the runway.