737 MAX Flight Crew Operations Manual
Automatic Flight -
System Description
4.20.18
MN-FLT-OH-201
Localizer and Glideslope Armed
After setting the localizer frequency and course, pushing the APP switch selects
the APP mode. The APP switch illuminates and VOR/LOC and G/S annunciate
armed. The APP mode permits selecting the second A/P to engage in CMD. This
arms the second A/P for automatic engagement after LOC and G/S capture and
when descent below 1500 RA occurs.
The localizer can be intercepted in the HDG SEL, CWS R or LNAV mode.
Glideslope (G/S) capture is inhibited prior to localizer capture.
Localizer Capture
The LOC capture point is variable and depends on intercept angle and rate of
closure. Capture occurs no later than 1/2 dot. Upon LOC capture, VOR/LOC
annunciates captured, SINGLE CH is annunciated for A/P status, the previous roll
mode disengages and the airplane turns to track the LOC.
Glideslope Capture
Glideslope capture is inhibited prior to localizer capture.
The G/S can be captured from above or below. Capture occurs at 2/5 dot and
results in the following:
• G/S annunciates captured
• previous pitch mode disengages
• APP light extinguishes if localizer has also been captured
• airplane pitch tracks the G/S
• GA displayed on thrust mode display (N1 thrust limit).
After VOR/LOC and G/S are both captured, the APP mode can be exited by:
• pushing a TO/GA switch
• disengaging A/P and turning off both F/D switches
• retuning a VHF NAV receiver.
After LOC and G/S Capture
Shortly after capturing LOC or G/S and below 1500 feet RA:
• the second A/P couples with the flight controls
• test of the ILS deviation monitor system is performed and the G/S and
LOC display turns amber and flashes
1B785, 1J585 - 1J594
• test of autopilot rudder servo is performed
• FLARE armed is annunciated
1B785, 1J585 - 1J594
• ROLLOUT armed is annunciated (as installed)
March 1, 2021