Narrative:

B737 systems manual clearly say that flight deck PA system overrides other communication in back. That is incorrect. When using the small black hand mike on the center console you do not override the flight attendants making a PA announcement. The F/as (flight attendants) were making a PA when the first officer (first officer) announced 'flight attendants be seated'. Therefore; they did not hear the announcement; and were not ready for takeoff.

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Original NASA ASRS Text

Title: B737 flight crew reported Flight Attendants were not seated for takeoff because the flight deck PA announcement did not override the cabin PA system.

Narrative: B737 systems manual clearly say that flight deck PA system overrides other communication in back. That is incorrect. When using the small black hand mike on the center console you do NOT override the flight attendants making a PA announcement. The F/As (Flight Attendants) were making a PA when the F/O (First Officer) announced 'Flight Attendants Be Seated'. Therefore; they did not hear the announcement; and were not ready for takeoff.

Data retrieved from NASA's ASRS site 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.