Narrative:

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.

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Original NASA ASRS Text

Title: 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.

Narrative: 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.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.