Narrative:

Air carrier X departing runway 28L. Air carrier Y landing runway 28L. Air carrier X was approximately 4000 feet down the runway when air carrier Y crossed the landing threshold. Recommendation; send air carrier Y around before crossing threshold.

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Original NASA ASRS Text

Title: SFO local controller experienced operational error when failing to issue go around to landing aircraft when separation between the landing and a departure aircraft was less than required.

Narrative: ACR X departing Runway 28L. ACR Y landing Runway 28L. ACR X was approximately 4000 feet down the runway when ACR Y crossed the landing threshold. Recommendation; send ACR Y around before crossing threshold.

Data retrieved from NASA's ASRS site as of April 2012 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.