Boeing 737 - 600/700/800/900. Operations Manual (1997 year)

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

PFD

MFD

ENGINE

MFD

PFD

MFD

MAIN PANEL DUs

LOWER DU

MAIN PANEL DUs

NORM

OUTBD

ENG

OUTBD

PFD

PRI

PFD

INBD

MFD

ENG SYS

MAIN PANEL DUs Switch to INBD ENG PRI

If the MAIN PANEL DUs switch is turned to INBD ENG PRI, the primary engine

display moves to the inboard DU, the PFD format is displayed on the outboard DU

and the upper DU blanks.

MAIN PANEL DUs Switch to INBD PFD

If the MAIN PANEL DUs switch is turned to INBD PFD, the PFD format is

displayed on the inboard DU and the outboard DU blanks.

MAIN PANEL DUs Switch to MFD

If the MAIN PANEL DUs switch is turned to INBD MFD, the PFD continues to

be displayed on the outboard display unit and the inboard display is blank. The

system format (SYS) or secondary engine format (ENG) can then be selected to

the inboard display unit and lower display unit with the MFD switches on the

engine display control unit.

10.21.10

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

Lower Display Switching

PFD

ENGINE

MAIN PANEL DUs

LOWER DU

MAIN PANEL DUs

NORM

OUTBD

ENG

OUTBD

PFD

PRI

PFD

INBD

MFD

PFD

ENGINE

PFD

MAIN PANEL DUs

LOWER DU

MAIN PANEL DUs

NORM

OUTBD

ENG

OUTBD

PFD

PRI

PFD

INBD

MFD

LOWER DU Switch to ENG PRI

If the LOWER DU switch is turned to ENG PRI, the engine display moves to the

lower DU and the upper DU blanks.

LOWER DU Switch to ND

If the LOWER DU switch is turned to ND, the engine display is shown on the

upper DU and the navigation display is shown on the lower DU. When the MFD

ENG switch is selected, the compact engine display is shown on the upper DU.

10.21.11

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

Display System Information Sources

Air Data Inertial Reference System (ADIRS)

The ADIRS produces flight data such as position, speed, altitude and attitude for

the flight displays, flight management computers, flight controls, engine controls

and all other systems requiring inertial and air data.

The major components of the ADIRS are:

• two air data inertial reference

• six static ports

units (ADIRUs)

• three pitot probes

• four air data modules (ADMs)

• two alpha vanes

• one inertial system display unit

• one total air temperature probe.

(ISDU)

• one dual mode select unit

(MSU)

AUXILIARY

ALPHA

CAPT

F/O

ALT

PITOT PROBE

VANE

STATIC

PORT

F/O PITOT PROBE

TO:STBY

AIRSPD

ADM

ADIRU-R

ADM

TO:

STBY

ADIRU-L

ADM

ALT/

AIRSPD

ADM

CAPT PITOT PROBE

TAT

PROBE

CAPT

F/O

ALT

ALPHA

STATIC

VANE

PORT

PITOT LINES

STATIC LINES

Air Data Inertial Reference Unit (ADIRU)

The ADIRUs provide inertial position and track data to the FMC as well as

attitude, altitude and airspeed data to the displays. The ADIRUs process

information measured by internal gyros and accelerometers, and from air data

module inputs, the alpha vanes and other systems.

The ADIRUs are described in Chapter 11, Flight Management, Navigation.

10.21.12

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

Air Data

The pitot static system is comprised of three separate pitot probes and six flush

static ports. Two pitot probes and four static ports interface with the air data

modules. The remaining auxiliary pitot probe and alternate static ports provide

pitot and static pressure to the standby instruments. The auxiliary pitot probe is

located on the first officer’s side of the airplane.

The air data modules convert pneumatic pressure to electrical signals and send

these data to the ADIRUs. Each pitot air data module is connected to its on-side

pitot probe; there is no cross connection. The air data module connected to the

Captain’s pitot probe sends information to the left ADIRU, while the air data

module connected to the First Officer’s pitot probe sends information to the right

ADIRU. The remaining air data modules are located at the balance centers of the

Captain’s and First Officer’s static ports. The air data module connected to the

Captain’s static ports sends information to the left ADIRU, while the air data

module connected to the First Officer’s static ports sends information to the right

ADIRU.

Angle-of-Attack

There are two alpha vanes, one located on each side of the forward fuselage. The

vanes measure airplane angle-of-attack relative to the air mass.

[Option - Angle of attack indicator]

The primary source of data for the AOA indicator on the PFD is supplied by the

ADIRU, with the SMYD as the backup source. The source selection is automatic

in the event of primary source failure. Slight differences between the Captain’s

and FO’s indications may be noticed due to sideslip or vane installation errors.

These differences could be as large as 2 degrees alpha.

Total Air Temperature

A total air temperature probe is mounted outside the airplane to sense air mass

temperature. The temperature sensed by the probe is used by the ADIRUs to

compute total air temperature.

Static Air Temperature

Static air temperature, displayed on the CDU PROGRESS page, comes from the

ADIRUs, using total air temperature probe information.

Standby Flight Instruments

The standby flight instruments include:

10.21.13

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

• standby magnetic compass

• integrated standby flight

display

• standby radio magnetic

indicator.

Standby Magnetic Compass

A standard liquid-damped magnetic standby compass is provided. A card located

near the compass provides heading correction factors.

Integrated Standby Flight Display (ISFD)

The ISFD displays attitude, airspeed, altitude, ILS, and heading information. It is

connected directly to the auxiliary pitot and alternate static sources. ILS

information is provided by the No. 1 ILS receiver. The display receives its heading

information from the same source as the captain’s primary flight display.

Note: The standby magnetic compass must be used to validate heading

information.

The battery bus powers the ISFD. Selecting the battery switch ON activates the

ISFD. After 10 seconds, an initialization sequence begins that requires 90 seconds

to complete. ATT and INIT 90s messages are displayed during initialization. Upon

completion of the initialization sequence, attitude information is displayed.

Note: Any change in airplane position during the initialization sequence may

result in an inaccurate alignment. Inaccurate alignment is not annunciated

and may result in the display of inaccurate attitude prior to, and during

flight. Re-initialization can only be accomplished through maintenance

action.

Detection of a momentary out-of-limit ISFD condition may cause the attitude

display to blank and the WAIT ATT or ATT:RST message to display. Operation of

the attitude reset switch is required in response to the ATT:RST message. This will

reset the horizon line with the airplane symbol.

Note: Operation of the attitude reset switch will not correct an inaccurate

alignment.

On the ground, operation of the attitude reset switch must be performed with the

airplane stationary. In flight, operation of the attitude reset switch must be

performed with the airplane in wings level, non-accelerated flight. During the

process, the ATT 10s message displays. Failure to maintain straight and level

flight for 10 seconds may result in an ATT:RST message. If the reset attempt is

unsuccessful, the ATT:RST message remains displayed and the ISFD does not

enter normal operation.

10.21.14

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

Standby Radio Magnetic Indicator

The standby radio magnetic indicator (RMI) displays magnetic heading and

VOR/ADF bearing to the station. The RMI is powered by the AC standby bus and

remains powered after the loss of all normal AC power as long as battery power

is available.

Clocks

[Option - GPS capable]

Two electronic clocks are installed, with two digital displays on each clock.

Universal time coordinated (UTC) time, UTC date, manual time or manual date

may be set on the upper time display. The lower ET/CHR display is used for either

elapsed time or the chronograph. Separate controls are provided for each display.

Each clock is powered by the hot battery bus when the battery bus is not available.

The clock reverts to hot battery bus power when the airplane is powered down.

The hot battery bus power keeps the time base but does not provide power for the

display or output of clock data and the clock reverts to manual mode. When the

airplane is powered up and Global Position System (GPS) data is restored, the

clock continues to operate in manual mode and will not automatically display

UTC time. UTC time can be manually selected by using the TIME/DATE

pushbutton.

Note: When on standby power, the F/O clock display is dim and UTC time is not

available.

Clock Switch

[Option - Remote clock switch]

A remote clock switch, on the glareshield panel, operates the same as the

chronograph (CHR) control.

Flight Recorder

The flight recorder provides a permanent record of selected operational and

systems information such as altitude, heading, acceleration, and airspeed. The

recorder is housed in a sealed, fire-resistant container located behind an access

door in the aft cabin ceiling.

Operational and systems information is automatically recorded whenever the

flight recorder is powered. On the ground, the recorder begins operating when one

of the engines is operating. In the air, the flight recorder is powered even with both

engines shut down as long as APU electrical power is available.

10.21.15

Flight Instruments, Displays -

PFD/ND System Description

Boeing 737 Operations Manual

Aircraft Condition Monitoring System (ACMS)

[Option]

The DFDAU receives signals representing certain flight condition and airplane

systems’ operating performance and converts them to a digital form for recording

on the DFDR.

The DFDR records airplane systems and flight data for at least the last 25 hours

of operation. The DFDR is located in the aft fuselage area.

[Option - Quick Access Recorder (QAR) lights]

A indicator on the Aft Overhead Panel illuminates when the quick access recorder

is full. The QAR is located in the electronics equipment bay.

10.21.16

Boeing 737 Operations Manual

Flight Instruments, Displays

Chapter 10

Head-Up Display System Description

Section 22

Introduction

The head-up display (HUD) system uses electronics and optics to calculate and

display flight information. The flight information is displayed as flight symbols

which project on to a transparent glass screen in front of the pilot. The flight

symbols overlay and combine with the outside view through window No. 1.

The HUD system can be used during manual flight operations, or with the AFDS

engaged during automatic flight operations. When used manually, internal HUD

guidance is used to control flight symbology and is independent of any AFDS

derived or displayed flight director guidance.

HUD system components, combined with other airplane systems, produce flight

symbology displayed in four distinct modes of operation. Each mode of operation

has unique characteristics, and is intended to be used during a particular phase of

flight based on system capability and meteorological conditions. TCAS resolution

advisories and system failure flags are also displayed when active. Detailed

information on display symbology is found in Section 42 of this chapter.

The HUD system consists of the following components:

• HUD computer

• Overhead unit (OHU)

• Combiner

• Control panel

• Annunciator panel

[Option - Model 2350]

• Drive electronics unit

HUD Computer

The HUD computer receives input signals from aircraft sensors and equipment

and converts this data to symbology for display on the combiner. The computer

also evaluates system and approach performance through extensive Built-In Test

Equipment (BITE), input validation, and approach monitor processing. If an out

of tolerance condition exists, the applicable annunciation appears on the combiner

and/or annunciator panel. Internal components control the following functions:

• Guidance control

• Shape and position of flight symbols

• Airplane sensor status

• HUD system status

• HUD system mode.

10.22.1

Flight Instruments, Displays -

Head-Up Display System

Description

Boeing 737 Operations Manual

Drive Electronics Unit

[Option - Model 2350]

The Drive Electronics Unit receives signals from the HUD computer and

conditions these signals to drive the projector in the OHU. Power supplies in the

Drive Electronics Unit supply power to the Drive Electronics Unit, OHU and

Combiner.

Overhead Unit (OHU)

The OHU contains the CRT and projection optics to display flight symbology on

the combiner. Electronic circuitry within the OHU controls display intensity and

system monitoring.

Combiner

The combiner optically combines flight symbology from the OHU, with the

pilot’s view through window No.1. It acts as a wavelength selective mirror,

reflecting only the flight symbology color (green) and lets other colors pass

through.

The combiner alignment detector monitors the angular position of the combiner.

The HUD computer uses the detector to verify correct combiner position for

normal viewing. If the combiner is not in the correct position, and the HUD is in

the IMC or VMC modes, the ALIGN HUD message appears on the combiner.

The combiner glass element has a break away safety feature which allows the

element to rotate forward from the normal position, in case of abnormal

deceleration.

Control Panel

The HUD control panel is used to select and display modes of operation and enter

data. Display intensity is controlled by panel switches or by an ambient light

sensor located on the upper left corner of the panel.

Annunciator Panel

The annunciator panel consists of lights to indicate HUD system status

annunciations during AIII mode approach and landing operations.

Modes of Operation

The HUD system provides a mode-selectable display on the combiner. The modes

are:

• PRI (Primary) - used for most HUD operations

• AIII - primarily used for manually flown CAT II or IIIa ILS approach and

landing operations

10.22.2

October 15, 2001

Flight Instruments, Displays -

Head-Up Display System

Description

Boeing 737 Operations Manual

• IMC - used for AFDS autopilot/flight director approaches

• VMC - used for visual approaches.

Primary (PRI) Mode

The primary mode may be used during all phases of flight from takeoff to landing.

This can include low visibility takeoff operations utilizing ground roll guidance,

all enroute operations and either non-precision or precision approaches to CAT I

or II minimums utilizing flight director guidance and/or raw data.

Attitude information is displayed in the form of a horizon line and pitch scales

positioned relative to an airplane reference symbol. Airspeed and altitude are

displayed in tapes along the left and right edges of the display. A sectored HSI is

displayed in flight in the lower center of the display. On the ground, the HSI, flight

path and guidance cue are not displayed. These symbols are automatically

displayed once the aircraft is in flight.

During takeoff, a TOGA pitch target line and a guidance cue are displayed. The

TOGA pitch target line is displayed as a horizontal dash line initially positioned

at the top of the display. As the pitch attitude increases during rotation, its vertical

position relative to the airplane reference symbol is adjusted to display the pitch

command from the Captain’s flight director. Initially, the flight director guidance

cue is displayed when the airplane reference is within 2 degrees of the TOGA

pitch target line or when climbing through 50 feet radar altitude, whichever occurs

first. The TOGA pitch target line remains until the TO/GA mode is exited. The

flight director guidance cue is displayed throughout flight when the Captain’s

flight director is selected on and both pitch and roll commands remain valid.

A full time slip-skid symbol is displayed as part of the roll scale. During any

takeoff

(after rotation) or go-around

(below 1000 feet), additional slip-skid

symbols are displayed to enhance lateral control in the event of an engine failure.

These two additional symbols are displayed relative to the airplane reference and

the flight path symbols and are removed above 1500 feet.

AFDS engaged modes, autothrottle modes and autopilot status is indicated across

the top of the display similar to the flight mode annunciator display. Navigation

information is displayed dependent on the selected navigation source and active

AFDS mode. During LNAV operations, vertical and lateral deviations are

similarly displayed based on FMC data. During ILS/VOR operations, course

deviation is displayed within the HSI. Glideslope data is presented on a glideslope

deviation scale adjacent to the altitude tape.

If the HUD is in a mode other than primary, depressing a TO/GA switch activates

the primary mode independent of the standby mode indicated on the HUD control

panel.

October 15, 2001

10.22.3

Flight Instruments, Displays -

Head-Up Display System

Description

Boeing 737 Operations Manual

Primary Mode - Low Visibility Takeoff

The primary mode includes special symbology used for a low visibility takeoff.

The display supports visual runway centerline tracking and enhances situational

awareness.

Note: Approval must be obtained from the appropriate regulatory authority prior

to conducting HUD low visibility takeoff operations.

The low visibility takeoff display incorporates a ground roll reference symbol,

ground roll guidance cue and a ground localizer line (if an ILS frequency is tuned

on both nav receivers). The HUD derived ground roll guidance cue provides

lateral guidance relative to the ground roll reference symbol to track the localizer.

The ground localizer line provides raw localizer information any time the aircraft

is on the ground and the Captain’s navigation receiver is tuned to a localizer

frequency. The localizer deviation is presented relative to the selected course mark

on the horizon.

Primary Mode - Approach and Landing

[Option - Model 2350]

If the primary mode is used for an approach and landing, flight director guidance

and navigation raw data is displayed. Once on the ground, the ground localizer

line is displayed (if an ILS frequency is tuned on both nav receivers) to enhance

centerline tracking.

AIII Approach Mode

[Option - Model 2350]

The HUD AIII mode is specifically designed for manual ILS approach and

landing operations to CAT II or CAT IIIa minimums. Altitude and airspeed tape

displays are replaced with digital values. The HSI is also replaced with ILS raw

data displayed in proximity to the flight path group around the center of the

display. In the AIII mode, flight path guidance is provided by the guidance cue

which is derived from internal approach and landing guidance algorithms, and is

independent of any AFDS derived or displayed flight director guidance.

Note: Approval must be obtained from the appropriate regulatory authority prior

to conducting HUD Cat II or CAT IIIa operations.

AIII mode is dependent on the availability of all required systems and ILS

approach criteria. Because of these requirements, the AIII mode is not identified

as a selectable standby mode until these requirements are met. AIII capability is

displayed on the control panel at any time, and on the combiner after LOC and G/S

capture in the PRI mode.

10.22.4

Flight Instruments, Displays -

Head-Up Display System

Description

Boeing 737 Operations Manual

ILS approach criteria requirements are satisfied when:

• Both VHF navigation receivers tuned to an ILS frequency, and

• VHF #1 or VHF #2 localizer deviation is less than approximately 1/4 dot

and glideslope deviation is less than approximately 1 and 1/4 dots for at

least five seconds, and

• The difference between the airplane’s magnetic track and the captain’s

selected course is less than 15 degrees, and

• Radio altitude is greater than 500 feet.

Note: Once these criteria have been satisfied, subsequent deviations outside the

criteria prior to AIII mode selection, will result in a loss of ability to select

the AIII mode.

Once the AIII mode is active, the AIII mode symbology and related annunciations

are displayed on the combiner, the control panel display, and the HUD annunciator

panel.

Any sensor or equipment condition that results in a loss of AIII capability will

cause a boxed NO AIII annunciation displayed on the combiner and on the control

panel display. The first officer’s AIII annunciation is also extinguished. The

annunciation will remain until another mode is selected or AIII capability is

regained.

Below 500 feet radar altitude, with a loss of AIII capability or if the approach or

flare performance does not ensure a safe touchdown within the required

touchdown zone, an APCH WARN annunciation will be displayed on the

combiner and on the HUD annunciator panel.

IMC Mode

The IMC mode is an alternate approach mode primarily intended for autopoilot

approaches. Like the PRI mode, the IMC mode guidance cue utilizes AFDS

derived guidance. The guidance cue is displayed when the Captain’s flight director

is active and both pitch and roll commands are valid.

Approach symbology format for the IMC mode is similar to the AIII approach

mode. Altitude and airspeed data is displayed as digital values and navigation raw

data is displayed in close proximity to the flight path vector.

VMC Mode

The VMC mode is intended for visual approach operations. No flight director or

HUD guidance is displayed. The flight path vector is used to control the approach

to the runway.

Approach symbology format for the VMC mode is similar to the AIII and IMC

modes. However, navigation data is not displayed.

10.22.5

Flight Instruments, Displays -

Head-Up Display System

Description

Boeing 737 Operations Manual

The proper mechanical alignment of the combiner is critical during visual

operations. Combiner position is monitored by the combiner alignment detector,

to determine if the combiner is within allowable position tolerances while in the

IMC or VMC mode. If its position is out of tolerance, an ALIGN HUD message

is displayed on the combiner. Elimination of the message is accomplished by

gently pushing the combiner in the breakaway direction and releasing. This allows

the combiner to reposition itself. If the message cannot be removed, the IMC or

VMC mode should not be used.

TCAS Resolution Advisory

TCAS resolution advisories are displayed as preventive and corrective symbols,

and are similar to the pitch commands displayed on the attitude indicator.

Preventive advisories do not require any crew action, but indicate an unsafe zone,

displayed as a double lined bracket. On the unsafe side of the bracket, two angled

lines are extended from the corners. The position of the bracket is determined by

TCAS, and represents the vertical flight path position that is safe.

Corrective advisories require positive action by the crew and are indicated by a

double lined box. The position of the box is determined by the vertical speed

requirements from TCAS, and represents the vertical flight path position that is

safe.

For additional information on TCAS, refer to Chapter 15, Warning Systems.

Failure Flags and Data Source Annunciations

Failure flags are displayed for invalid sensor status and miscompares between

similar parameters. These flags are generally indicated by boxed annunciations for

the affected parameters, and in the case of failure, the removal of all symbols

related to the fault. In some cases, symbols are removed as a result of other

symbols being removed due to a fault.

Flags associated with a miscompare of similar data result in the display of a flag

without the removal of the related symbols. The flag indicates the applicable data

should be verified by cross-checks with other flight deck displays.

Data source annunciations are provided in a few cases to annunciate the source of

displayed data when other than normal.

Dashes replace numbers if there is no computed data.

10.22.6

Boeing 737 Operations Manual

Flight Instruments, Displays

Chapter 10

Electronic Flight Instrument System (EFIS)

Section 30

Introduction

The electronic flight instrument system (EFIS) presents a dynamic color display

of the parameters necessary for flight path control. The displays provide the

following information:

• flight mode annunciation

• approach minimums

• airspeed

• radio altitude

• attitude

• altitude

• steering information

• vertical speed

• instrument landing system

• GPWS annunciations

display

• TCAS indications.

Failure flags are displayed for airplane system failures. Displayed information is

removed or replaced by dashes if no valid information is available to the display

system (because of out-of-range or malfunctioning navigation aids). Displays are

removed when a source fails or when no system source information is available.

Flight mode annunciations are described in Chapter 4, Automatic Flight.

Airspeed

Airspeed is displayed on a round dial Mach/airspeed indicator, or MASI. Current

airspeed is displayed by an airspeed pointer and digital counter. Current Mach

number is digitally displayed when the Mach number is greater than 0.40. Target

airspeed is shown by the magenta airspeed cursor.

Takeoff and landing reference speeds and flap maneuvering speeds are shown

along the circumference of the indicator. Maximum and minimum airspeeds are

also displayed.

Attitude

The attitude indicator displays airplane pitch and roll attitude referenced to the

horizon.

Pitch attitude is displayed by an airplane symbol against a pitch scale. The pitch

scale is in 2.5 degree increments.

A pointer indicates bank angle in increments of 10, 20, and 30 degrees. Single

marks indicate 45 and 60 degrees of bank. A small rectangle under the bank angle

pointer indicates slip and skid conditions. Bank angle is also represented by the

attitude of the airplane symbol against the horizon line and pitch scale.

10.30.1

Flight Instruments, Displays -

Electronic Flight Instrument

System (EFIS)

Boeing 737 Operations Manual

[Option - PLI pop-up]

A pitch limit indication is displayed at all times when the flaps are not up, or when

flaps are up and airspeed approaches stick shaker activation for existing flight

conditions.

Steering Indications

[Option - Split axis command bars]

Flight director pitch and roll bars are displayed when the related flight director

switch is on. Pitch and roll commands are displayed independently.

[Option - Flight path vector]

The flight path vector

(FPV) symbol represents airplane flight path angle

vertically and drift angle laterally. The flight path vector is displayed on the

attitude indicator when the EFIS control panel FPV switch is selected on.

The FPV symbol is displayed in two brightness levels. The FPV symbol is

displayed dim when either the flight director or a TCAS resolution advisory is

displayed.The FPV symbol is displayed bright when the flight director is off and

there is no TCAS resolution advisory displayed.

Instrument Landing System Indications

ILS glide slope and localizer deviation are provided.

The glide slope pointer and scale appear on the right side of the attitude indication

when a valid signal is received. The scale turns amber and the pointer flashes to

indicate an excessive glide slope deviation. The pointer is not displayed when the

glide slope signal is unusable or when the track and the front course on the mode

control panel differ by more than 90 degrees (backcourse).

The localizer pointer and scale appear at the bottom of the attitude indicator when

a valid signal is received. When the course deviation is slightly more than

one-half dot and the localizer mode is engaged and track is within 5 degrees of the

MCP selected course, the scale automatically expands. At low radio altitudes,

with autopilot or flight director engaged, the scale turns amber and the pointer

flashes to indicate excessive deviation. Below 1,000 feet AGL, with LNAV

engaged and LOC armed, the localizer scale turns amber and the pointer flashes if

the localizer is not captured.

Each pilot’s deviation alerting system self-tests upon becoming armed at 1500 feet

radio altitude. This self-test generates a two second LOC and G/S deviation

alerting display on each attitude indicator.

10.30.2

October 15, 2001

Flight Instruments, Displays -

Electronic Flight Instrument

System (EFIS)

Boeing 737 Operations Manual

[Option - Rising runway]

Below 2500 feet radio altitude, with the localizer pointer in view, a rising runway

symbol comes into view. The symbol provides lateral guidance. At 200 feet radio

altitude, the symbol rises toward the airplane symbol.

Approach Minimums

[Option - Radio altitude below ADI]

The selected radio altitude set on the EFIS control panel is displayed near the

bottom right of the attitude indicator. The barometric approach minimums is

displayed as a marker on the altimeter.

Radio Altitude

[Option - Radio altitude below ADI, round dial]

The current radio altitude is displayed near the bottom right of the attitude

indicator when radio altitude is below 2,500 feet AGL. When between 1000 feet

and 2500 feet AGL, the readout is digital. When below 1000 feet AGL, the

readout is displayed in a round dial format. The display turns amber and the

circumference flashes for 3 seconds as the radio altitude descends through the

selected minimum altitude. The display changes back to white after one of the

following occurs:

• when passing the selected minimum altitude plus 75 feet during

go-around

• at touchdown

• after pressing the RST switch on the EFIS control panel.

Radio Altitude Alert

[Option - 2500 ft height alert]

The altitude alert is triggered and “ALT” is shown above the radio altitude display

when radio altitude is less than or equal to 2500 feet AGL.

Altitude

Altitude is displayed on a round dial altimeter. Current altitude is displayed by an

altitude pointer and a digital readout. A green reference altitude marker indicates

the barometric minimums set on the EFIS control panel.

When meters is selected on the EFIS control panel, current altitude in meters is

shown above the altitude window and the metric altitude equivalent of the selected

MCP altitude is displayed above the altimeter. Metric readouts are not available in

the compact EFIS mode.

10.30.3

Flight Instruments, Displays -

Electronic Flight Instrument

System (EFIS)

Boeing 737 Operations Manual

The current barometric reference is displayed in either inches of mercury or

hectopascals as selected on the EFIS control panel.

Vertical Speed

Vertical speed is indicted by a vertical speed pointer. The pointer depicts rate of

climb or descent from 0 to 6000 feet.

Traffic Alert and Collision Avoidance (TCAS) Indications

[Option - VSI TCAS advisory]

TCAS resolution advisories are displayed on the attitude indicator and vertical

speed indicator.

Refer to Chapter 15, Warning Systems.

GPWS Warnings

GPWS warnings are displayed in large capital letters on the attitude indicator.

Refer to Chapter 15, Warning Systems.

10.30.4

Boeing 737 Operations Manual

Flight Instruments, Displays

Chapter 10

Primary Flight Display (PFD)

Section 31

Introduction

The primary flight displays (PFDs) present a dynamic color display of all the

parameters necessary for flight path control. The displays provide the following

information:

• flight mode annunciation

• radio altitude

• airspeed

• instrument landing

• altitude

system display

• vertical speed

• approach minimums

• attitude

• heading/track indications

• steering information

• TCAS indications

• GPWS annunciations.

Failure flags are displayed for airplane system failures. Displayed information is

removed or replaced by dashes if no valid information is available to the display

system (because of out-of-range or malfunctioning navigation aids). Displays are

removed when a source fails or when no system source information is available.

Flight mode annunciations are described in Chapter 4, Automatic Flight.

Airspeed

[Option - Without groundspeed displayed]

Airspeed is displayed on a tape and in a digital window on the left side of the PFD.

The current Mach number is digitally displayed below the airspeed tape when the

current Mach number is greater than 0.40. An airspeed trend vector indicates

predicted airspeed in

10 seconds. Selected airspeed is displayed above the

airspeed tape.

[Option - With groundspeed displayed]

Airspeed is displayed on a tape and in a digital window on the left side of the PFD.

The current Mach number is digitally displayed below the airspeed tape when the

current Mach number is 0.40 Mach or above. Ground speed is displayed when

airspeed decreases below 0.40 Mach. An airspeed trend vector indicates predicted

airspeed in 10 seconds. Selected airspeed is displayed above the airspeed tape.

Takeoff and landing reference speeds and flap maneuvering speeds are shown

along the right edge of the airspeed tape. Maximum and minimum airspeeds are

also displayed along the right edge of the airspeed tape.

10.31.1

Flight Instruments, Displays -

Primary Flight Display (PFD)

Boeing 737 Operations Manual

Attitude

The attitude indication displays the airplane pitch and roll attitude referenced to

the horizon.

Pitch attitude is displayed by an airplane symbol against a pitch scale. The pitch

scale is in 2.5 degree increments.

A pointer indicates bank angle in increments of 10, 20, and 30 degrees. Single

marks indicate 45 and 60 degrees of bank. A small rectangle under the bank angle

pointer indicates slip and skid conditions. Bank angle is also represented by the

attitude of the airplane symbol against the horizon line and pitch scale.

[Option - PLI pop-up]

A pitch limit indication is displayed at all times when the flaps are not up, or when

flaps are up and airspeed approaches stick shaker activation for existing flight

conditions.

Angle of Attack

[Option - Angle of Attack Indicator]

The Angle of Attack (AOA) indicator displays aircraft body angle of attack, stick

shaker angle of attack, and the appropriate range of approach angle of attack. The

indicator is located in the upper-right corner of the PFD, above the ADI.

If the AOA signal is determined to have failed or is invalid when ground speed is

greater than 80 knots, the AOA indicator will be blanked and replaced with a fail

flag.

During normal operation, the approach reference band moves with flap handle

position. When the flap handle is in a landing flap detent, the band will depict the

appropriate range of AOA for a Vref(xx)+5 approach, where Vref(xx) is for the

corresponding flap detent position. If the flaps are driven in alternate mode, the

band moves depending on actual flap position. If flap position is determined to be

invalid, the band is blanked.

If an approach is flown faster than Vref(xx)+5, AOA is lower than normal and

could potentially be below the band. If a slower approach is flown, AOA is higher

than normal and could be above the band.

Steering Indications

[Option - Integrated cue command bar]

The flight director is displayed when the related flight director switch is on. Pitch

and roll commands are combined on a single display.

10.31.2

Flight Instruments, Displays -

Primary Flight Display (PFD)

Boeing 737 Operations Manual

The flight path vector

(FPV) symbol represents airplane flight path angle

vertically and drift angle laterally. The flight path vector is displayed on the PFD

when the EFIS control panel FPV switch is selected on.

The FPV symbol is displayed in two brightness levels. The FPV symbol is

displayed dim when either the flight director or a TCAS resolution advisory is

displayed.The FPV symbol is displayed bright when the flight director is off and

there is no TCAS resolution advisory displayed.

Instrument Landing System Indications

ILS glide slope and localizer deviation, frequency/identification, DME, course,

and marker beacon indications are provided.

The approach reference information appears above and to the left of the attitude

display. The ILS station identification or frequency, course, and (if available)

DME are displayed.

The marker beacon indication (OM - outer marker, IM - inner marker, or MM -

middle marker) is displayed in the upper right corner of the attitude display area.

The glide slope pointer and scale appear on the right side of the attitude indication

when a valid signal is received. At low radio altitudes, with autopilot or flight

director engaged, the scale turns amber and the pointer flashes to indicate an

excessive glide slope deviation. The pointer is not displayed when the glide slope

signal is unusable or when the track and the front course on the mode control panel

differ by more than 90 degrees (backcourse).

The localizer pointer and scale appear at the bottom of the attitude indication when

a valid signal is received. When the course deviation is slightly more than

one-half dot, the localizer mode is engaged and track is within 5 degrees of the

MCP selected course, the scale automatically expands. At low radio altitudes,

with autopilot or flight director engaged, the scale turns amber and the pointer

flashes to indicate excessive deviation. Below 1,000 feet AGL, with LNAV

engaged and LOC armed, the localizer scale turns amber and the pointer flashes if

the localizer is not captured.

Each pilot’s deviation alerting system self-tests upon becoming armed at 1500 feet

radio altitude. This self-test generates a two second LOC and G/S deviation

alerting display on each attitude indicator.

[Option - Rising runway]

Below 2500 feet radio altitude, with the localizer pointer in view, a rising runway

symbol comes into view. The symbol provides lateral guidance. At 200 feet radio

altitude, the symbol rises toward the airplane symbol.

10.31.3

Boeing 737 - 600/700/800/900. Operations Manual (1997 year) - page 51