Heading Selector
Rotate –
.
sets heading in HEADING display
.
positions selected heading bugs on both HSIs.
HEADING Display
Displays selected heading – same heading as HSI selected heading bug.
LNAV Switch
Push –
.
commands AFDS roll to intercept and track the active FMC route
.
annunciates LNAV as roll mode and illuminates LNAV switch light. LNAV Mode
In LNAV mode, the FMC controls AFDS roll to intercept and track active FMC route. Active route is entered and modified through FMC CDUs and can include SIDs, STARs, and instrument approaches.
Automatic Flight -Controls and Indicators 737 Operations Manual
LNAV engagement criteria:
.
active route entered in FMC
.
within 3 NM of active route, LNAV engagement occurs with any airplane
heading
. outside of 3 NM, airplane must:
.
be on intercept course of 90 degrees or less
.
intercept route segment before active waypoint.
LNAV automatically disconnects for following reasons:
.
reaching end of active route
.
reaching a route discontinuity
.
intercepting or missing the intercept of a selected approach course in
VOR LOC or APP modes (VOR/LOC armed)
.
selecting HDG SEL
.
loss of capture criteria.
VOR Localizer (LOC) Switch
Push –
.
commands AFDS roll to capture and track selected VOR or LOC course
.
annunciates VOR/LOC armed or engaged as roll mode and illuminates
VOR LOC switch light.
VOR LOC Mode
Pushing the VOR LOC switch selects VOR mode if a VOR frequency is tuned or selects LOC mode if a localizer frequency is tuned.
The VOR mode provides roll commands to track selected VOR course.
The LOC mode provides roll commands to track selected localizer course along inbound front course bearing.
The selected course can be intercepted while engaged in:
.
LNAV
.
HDG SEL
.
CWS R if an autopilot is engaged in CMD.
The capture point is variable and depends on intercept angle and closure rate. Localizer capture occurs not later than 1/2 dot deviation. Course capture is indicated when VOR/LOC annunciation changes from armed to engaged.
Copyright . The Boeing Company. See title page for details.
4.10.10 December 1, 2000
Automatic Flight -Controls and Indicators 737 Operations Manual
While engaged in VOR or LOC modes:
.
A autopilot and Captain’s F/D use information from Captain’s course
selector and No. 1 VHF NAV receiver
.
B autopilot and First Officer’s F/D use information from First Officer’s
course selector and No. 2 VHF NAV receiver
.
different courses and/or frequencies for two VHF NAV receivers can
cause disagreement between the Captain’s and First Officer’s F/D
displays and affect A/P operation.
Note: When a localizer frequency is selected, VHF NAV radios automatically switch from tail antenna to nose antenna when VOR/LOC is annunciated (armed or engaged). If antenna switching does not occur, LOC mode is inhibited.
Note: Localizer backcourse tracking is not available.
Course Selector
Sets course in COURSE display for related VHF NAV receiver, AFDS and HSI. Two course selectors and COURSE displays are located on the MCP.
Rotate Captain’s course selector – provides selected course information to:
.
A FCC
.
No. 1 VHF NAV receiver
.
Captain’s HSI course pointer and course deviation bar.
Note: In VOR LOC or APP mode, the A A/P and Captain’s F/D use selected course and navigation data from the No. 1 VHF NAV receiver.
Rotate First Officer’s course selector – provides selected course information to:
.
B FCC
.
No. 2 VHF NAV receiver
.
First Officer’s HSI course pointer and course deviation bar.
Note: In VOR LOC or APP mode, B A/P and First Officer’s F/D use selected course and navigation data from No. 2 VHF NAV receiver.
Bank Angle Selector
Rotate –
.
Sets maximum bank angle for AFDS operation in HDG SEL or VOR
modes
.
commanded bank angle can be selected at 10, 15, 20, 25, or 30 degrees.
Automatic Flight -Controls and Indicators 737 Operations Manual
Heading Select (HDG SEL) Switch
Push –
.
engages HDG SEL command mode
.
commands roll to follow selected heading
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本文链接地址：737-300机组操作手册Flight Crew Operations Manual FCOM 2(24)
