Boeing 737-800 - AFDS Status Annunciation; AFDS Flight Mode Annunciations

737 Flight Crew Operations Manual
Automatic Flight -
System Description
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4.20.4 D6-27370-866-EGP
F/D modes are controlled directly from the respective FCC under certain
conditions. This independent F/D operation occurs when neither A/P is engaged
in CMD, both F/D switches are ON and one of the following mode conditions
exists:
• APP mode engaged with LOC and G/S captured
• GA mode engaged and below 400 feet RA
• TO mode engaged and below 400 feet RA.
YW273, YW274
For non-approach modes, if the pilot is flying manually but not following the
flight director guidance in the roll mode and then selects autopilot CMD
engagement, the autopilot will engage into the current flight director role mode.
Independent F/D operation is indicated by illumination of both MA lights. When
independent operation terminates, the MA light extinguishes on the slaved side.
If a generator is lost during a F/D TO or GA, or while in dual F/D APP mode
below 800 feet, the FCC on the unaffected side positions the F/D command bars
on both attitude indicators. If the F/D MA light on the affected side had been
illuminated, it extinguishes upon electrical bus transfer.
AFDS Status Annunciation
The following AFDS status annunciations are displayed in the A/P status display
located above the attitude indicator on the outboard display unit:
• CMD (one or both autopilots are engaged)
• FD (the flight director is ON and the autopilot is either OFF or engaged
in CWS)
• CWS P (pitch mode engaged in CWS)
• CWS R (roll mode engaged in CWS)
• SINGLE CH (for single A/P ILS approach, annunciates after localizer
capture and remains on for entire approach. For dual A/P ILS approach,
annunciates after localizer capture and extinguishes after pitch monitor
confidence test is successfully completed).
AFDS Flight Mode Annunciations
The flight mode annunciations are displayed just above the attitude indicator on
the outboard display unit. The mode annunciations, from left to right, are:
• autothrottle
•roll
•pitch.
Engaged or captured modes are shown at the top of the flight mode annunciation
boxes in large green letters. Armed modes are shown in smaller white letters at the
bottom of the flight mode annunciation boxes.
September 15, 2016