CHAPTER 15

NAVIGATION SYSTEM

Page

TABLE OF CONTENTS 15-00-01/02

DESCRIPTION

General 15-10-01

Description 15-10-01

Controls and Indicators 15-10-04

COMPONENTS (NOT USED)

CONTROLS AND INDICATORS 15-30-01

FUNCTIONAL SCHEMATICS (NOT USED)

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NAVIGATION SYSTEMS

GENERAL

The navigation system includes thoseunits and components which providetime and position data to the flightcrew. The system encompasses bothground dependent and independentposition indicating systems; atti-tude, directional, speed, tempera-ture, and altitude instruments; thoseunits which provide guidance duringapproach, landing, and taxiing; andthose units which combine the variousnavigational inputs to compute and/ordisplay a geographical location.

DESCRIPTION

CLOCKS

A digital time system is installedwhich is a crystal controlled, solidstate timepiece compatible with com-puter associated operations requiringa highly accurate and controlled realtime reference. The display presentsGreenwich Mean Time (GMT) in hoursand minutes, Long Term Elapsed FlightTime (ELAPS) in hours and minutes,and Short Term Elapsed Time (CHRO) inminutes and seconds. Digital GMToutputs are available for InertialNavigational Systems (INS), and aDigital Flight Data Recorder (DFDR).

ATTITUDE DIRECTOR INDICATOR

In addition to its flight instrumentrole, the Attitude Director Indicator(ADI) provides data which are usedfor navigation, approach, and landingoperations. The command bars providea means of displaying computed flightdirector commands or monitoring auto-pilot operations. Vertical deviation

from the glide slope is indicated bythe glide slope pointer. The pitchcommand bar provides computed alti-tude or altitude hold commands aswell as speed command pitch attitudeinformation. The pitch command baralso displays speed guidance commandsfor the takeoff and go-around modes.Lateral corrections to intercept aselected VOR/LOC or INS centerline orheading can be shown by the rollcommand bar, and lateral deviationfrom the localizer centerline isindicated by the localizer indicator.

RADIO MAGNETIC INDICATOR

The Radio Magnetic Indicator (RMI)displays relative bearing informationfrom ADF and VOR signal sources onthe respective RMI pointer, andmagnetic heading from the compasssystem under the lubber line.Compass system number 1 normallyfurnishes magnetic heading to thecopilot's RMI. Compass systemnumber 2 normally furnishes magneticheading to the Captain's RMI. Whenthe COMP selector knob is placed atBOTH ON 1 (BOTH ON 2) position thenumber one (two) compass systemprovides magnetic heading for boththe Captain's and Copilot's RMI's.

HORIZONTAL SITUATION INDICATOR

The Horizontal Situation Indicator(HSI) displays commands from threedifferent sources (VOR, ILS, andINS). Inputs are controlled by theHSI switch on the FGS panel. The HSIdisplays are; magnetic or true head-ing, selected course or desired

course, true track and crosstrack deviation.Glideslope deviation, distance to the nextwaypoint and selected heading are also dis-played.

MARKER BEACON SYSTEM

The pre-tuned marker beacon system providesvisual and aural signals to the flight crew.Three dimmable lights on the Captain's andCopilot's instrument panels provide visualposition indications when passing over theouter, middle, or airways marker. A MARKERselector located on the SELCAL panel permitsselection of HI or LO sensitivity.

STANDBY MAGNETIC COMPASS

The standby magnetic compass provides aheading reference in relation to magneticnorth.

TAS/SAT INDICATOR

True airspeed, derived from pilot system inputand computer corrections for temperature,compressibility, pressure altitude, and posi-tion error is displayed, together with static airtemperature, on the TAS/SAT indicator.Total air temperature may be read by pushingthe TAT button the TAS/SAT indicator andreading same in SAT readout.

WEATHER RADAR SYSTEM

The weather radar system displays weatherand ground-targets, in color, with selective

ranges of 25, 50, 100, 150 and 300 nauticalmiles. In NORM mode, green color depictslight rainfall/light turbulence, yellow colordepicts medium rainfall/medium turbulence,red color depicts heavy rainfaH/heavy tur-bulence and potential hail conditions! In MAPmode, green color represents targets with lowreflectivity and yellow color represents targetwith medium reflectivity, and red color repre-sents tragets with high reflectivity.

The antenna is gyro-stabilized in pitch and roll(±45°) and is pitch controllable from 14degrees UP to 14 degrees DN (down). Inaddition, each radar indicator has azimuthlines (supplying target bearing reference) andrange marks (to aid in distance determination).

NOTE Actual tilt performance is up to 14°although index on the controlpanel is 15°.

INERTIAL NAVIGATION SYSTEM(Applicable to aircraft with INS installed)

The Inertial Navigation System (INS) is self-contained and functions without groundbased aids. It supplies continuous positionand navigation data in readable form for thepilots reference. The INS may be coupled tothe flight guidance system to provide automat-ic flight. A precision gyro-stabilized platformis used for reference, and a digital computerperforms data computation and eventprogramming to generate navigational data.The INS gyro platform also supplies atti-tude reference signals for the ADI, FGS,

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AT/SC, radar antenna and PAFAM; andazimuth stabilization signals for thecompass system. Three completeInertial Navigation Systems areinstalled. Cockpit controls consistsof three Mode Selector Units (MSU) onthe overhead panel and three ControlDisplay Units (CDU) on the pedestal,No. 1 and No. 2 forward and No. 3 aftof the throttle quadrant.

A backup battery unit is provided foreach INS and will supply essentialpower to maintain INS operationduring ac power interruptions. Afully charged battery unit willsustain operation of the INS forapproximately 15 minutes.

CAUTION; OPERATING THE INS ON THEGROUND WITH AC POWERREMOVED WILL CAUSE DEPLE-TION OF THE BACKUP BATTERYUNIT SYSTEM OVERHEAT DUETO NO AIR FLOW. AN AURALWARNING HORN, LOCATED INTHE RIGHT AIR CONDITION-ING COMPARTMENT, WILL SOUNDIF THE INS IS OPERATINGWITH THE AIRCRAFT ON THEGROUND AND AC POWER ISREMOVED.

GROUND PROXIMITY WARNING SYSTEM(GPWS)

The ground proximity warning systemconsists of a ground proximity warn-ing computer which utilizes inputsfrom the Air Data Computer-1, RadioAltimeter-1, ILS Receiver-1, and flapand landing gear sensors. The com-puter processes the radio altitude,barometric altitude rate, glideslopedeviation, and landing gear and flapposition information to determineundue proximity with the ground. Thecomputer provides audio outputs and

activates visual annunciators to indi-cate an unsafe flight path in rela-tion to the ground or that aircraftis not in proper configuration fordescent between 2450 feet and 50 feetradio altitude. The audio outputsare, "Whoop, whoop, pull up" and"glideslope". The visual annuncia-tors consist of red GPWS lights andamber BELOW G/S switch lights locatedon the Captain's and First Officer'sglareshields.

A GPWS FAIL light, located on theFlight Engineer's annunciator panel,will come on to indicate GPWS failureindications in the event of groundproximity warning computer or GPWSsensor failure.

GPWS can be self-tested by pushingthe GND PROXIMITY test button,located on the overhead panel, whilethe aircraft is on the ground orin-flight above 1000 feet radioaltitude. GPWS FAIL light must beoff and flaps must be in non-landingconfiguration. During a successfulself-test the aural annunciators,"Whoop, whoop, pull up" and, "Glide-slope", both red GPWS (flashing)lights, both amber BELOW G/S switchlights, and the GPWS FAIL light areactivated. The test checks thecomputer operation, electrical power,radio altitude and barometric alti-tude rate validities, and landinggear and flap positions.

The GPWS can be deactivated by open-ing the GND PROXIMITY WARN circuitbreaker located on the Flight Engi-neer's Overhead Circuit BreakerPanel. This may be used to preventor to silence inappropriate GPWSwarning or alert.

Ground Proximity Warning

The GPWS will provide visual GPWS(flashing) and aural, "Whoop, whoop,

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Vol. III15-10-03

pull up" annunciations of possiblepremature contact with terrain underthe following four conditions:

Mode 1 - Excessive rate of descent -A warning is provided when the ter-rain clearance is less than 2450 feetAGL and barometric altitude rate indi-cates the aircraft is descending atan excessive rate regardless of air-craft configuration.

Mode 2 - Excessive terrain closurerate - A warning is provided when theterrain clearance is less than 1800feet AGL and the terrain is risingtoward the aircraft or the aircraftis closing with the terrain at anexcessive rate.

Mode 3 - Descent after takeoff andmissed approach - A warning isprovided after takeoff or duringgo-around between 50 feet and 700feet AGL if the barometric altitudeloss is excessive. The GPWS revertsto Mode 3 when the aircraft is below50 feet AGL. The GPWS will alsorevert to Node 3 when aircraft isbelow 500 feet AGL with landing gearand flaps in landing configurationand flaps are selected to a non-landing configuration.

Mode 4 - Inadvertent proximity toterrain in non-landing configuration -A warning is provided during cruiseor landing approach if landing gearare not down below 500 feet AGL or ifflaps are in non-landing configura-tion below 200 feet AGL. Addi-tionally, a warning is providedbetween 500 feet and 200 feet AGLwith flaps in non-landing configura-tion and aircraft sink rate is

excessive. Mode 4 is automaticallyarmed when the aircraft ascends above700 feet AGL.

NOTE; A guarded GND PROXIMITY WARNFLAP OVRD switch, located onthe aft overhead panel, pro-vides the capability topreclude warning of aircraftnot in landing configurationwhen usable to obtain landingflaps.

Glideslope Alert

The GPWS will provide visual BELOWG/S and aural "Glideslope" alertannunciations under the followingcondition:

Mode 5 - Glideslope alert - A glide-slope alert is provided when air-craft deviates excessively belowthe glideslope. Mode 5 is armed whenaircraft is between 1000 feet and 50feet AGL with landing gear down andILS frequency selected on the ILSreceiver. The aural "Glideslope"alert can be either a "soft" or"hard" alert. A "soft" alert isactivated when aircraft deviatesexcessively below the glideslope ataltitudes below 1000 feet AGL andconsists of "Glideslope" repeated atan audio level lower than the "Pullup" level. The repetition rate ofthe "soft" alert is a function ofradio altitude and glideslope devia-tion such that the repetition rateincreases with decreased radio alti-tude and increased glideslope devia-tion. A "hard" alert is activatedwhen aircraft deviates excessivelybelow the glideslope at altitudesbelow 300 feet AGL and consists of

JL15-10-04 May 1/83

"Glideslope" repeated at an audiolevel equal to "Pull up" level.

NOTE; GPWS modes 1 through 4 havepriority over mode 5.

Theglideslope alert can be inhibited ataltitudes below 1000 feet AGL (eitherprior to or during a "soft" alertonly) by momentarily pushing theBELOW G/S switch-light. The glide-slope alert inhibit can be cancelledby descending below 50 feet AGL orclimbing above 1000 feet AGL. Theglideslope alert is automaticallyinhibited when the flight directorBack Course mode is selected.

CONTROLS AND INDICATORS

The navigational controls and indi-cators are on the Captain's and FirstOfficer's instrument panels, theOverhead instrument panel and thePedestal. Illustrations of thesemajor panels are in Chapter 1. Theindividual controls and indicatorsare illustrated and described inanother section of this chapter.

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NAVIGATION SYSTEMS - Controls and Indicators

GND SPEED Readout

Displays current ground speed.

Heading Bug

A moveable index which indicates se-lected heading when controlled by theheading selector knob on the FGSpanel or indicates true/track drift anglewhen controlled by the INS.

NAV Source Annunciator

RAD - Indicates which radio is provid-ing navigational signals to theHSI.

INS - Indicates which inertial naviga-tion system is providing navi-gational signals to the HSI.

Course Deviation Scale

Indicates amount of deviation from thecenterline of the selected course.

ALERT Annunciator

Comes on 90 seconds before each INStrack leg is reached and then eithergoes off when a track leg change isautomatically made or flashes to indi-cate that a track leg change must bemanually initiated.

Compass Card

A rotating card which is oriented tomagnetic north by signals from thecompass system (HSI switch in RAD)or to true north by signals from the INS(HSI switch in INS).

Reciprocal Arrow

Point to the reciprocal airplane headingon the compass card.

HORIZONTAL SITUATIONINDICATOR (HSI)

CAPTAIN'S AND COPILOT'SINSTRUMENT PANELS

TRU/MAG Annunciator

MAG - Indicates HSI switch is in RADposition and the heading underthe lubber line is magneticheading.

TRU - Indicates HSI switch is in INSposition and the heading underthe lubber line is true heading.

MILES Readout

Displays distance as measured betweenthe airplanes present position and thenext selected waypoint.

Course Pointer

Indicates selected course when the HSIswitch is in the RAD position and indi-cates desired track between from andto waypoints when the HSI switch is inthe INS position.

Glide Slope Pointer

The pointer indicates position of glideslope relative to the position of the air-plane.

Course Deviation Indicator

Indicates the position of selected VORcourse or ILS localizer (HSI switch inRAD) or INS desired track (HSI switch inINS) in relation to the airplane's position.

To/From Indicator

To - Indicates that the selected(Displayed) course, if flown, will take the

airplane toward the station.

From - Points toward tail of coursepointer and indicates that theselected course, if flown, willtake the airplane away fromthe station.

Symbolic Airplane

Indicates position in relation to course.

NAVIGATION SYSTEMS - Controls and Indicators

INS WarningsBlank indicates data are unusable.Broken line indicates no computeddata displayed.

Nav Fail FlagAppears when navigation data are un-usable.

HEADING FlagAppears when the heading data areunusable.

GS FlagAppears when glide slope data areunusable.

HORIZONTAL SITUATION INDICATOR (HSI)WITH FLAGS DISPLAYED

CAPTAIN'S AND COPILOTSINSTRUMENT PANELS

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NAVIGATION SYSTEMS - Controls and Indicators

Compass Card

A rotating compass card whichindicates the airplane's headingas read under the lubber line.

OFF Flag

Appears when heading data areunusable.

No. 2 Pointer

Points to the relative bearing ofthe selected VOR or ADF facility.

No. 1 ADF/VOR Selector

Permits selection of either a VORor ADF station as the signalsource for the No. 1 pointer.

Lubber Line

Points to the airplane's headingon the adjacent rotating compasscard.

No. 1 Pointer

Points to the relative bearing ofthe selected VOR or ADF facility.

No. 2 ADF/VOR Selector

Permits selection of either a VORor ADF station as the signalsource for the No. 2 pointer.

Reciprocal Arrow

Points to the airplane's recipro-cal heading.

RADIO MAGNETIC INDICATOR (RMI)(CAPTAIN'S AND COPILOT'S INSTRUMENT PANELS)

ADF TONE Switch

ON - Superimposes an auralsignal on unmodulatedcarrier waves to aid inprecise frequency selection.

ADF Selector Light (2)

Indicates which ADF frequency is inuse.

ADF Function Selector

ADF - Antenna will automaticallyseek the signal source anddisplay relative bearing onthe RMI.

ANT - A non-directional antennaposition used for rangenavigation, optimum sta-tion tuning, or monitor ofcommercial broadcast.

TEST - Pointers on ADF/RMI's dis-play 315° relative bearing.

TFR Selector

Permits operator to receive oneither of the selected ADF frequen-cies.

ADF Frequency Indicator (2)

Displays the selected frequency.

ADF Frequency Selector (2)

Rotate to select desired stationfrequency.

ADF GAIN Knob

Rotate to control volume.AUTOMATIC DIRECTION FINDER(ADF)

PEDESTAL

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NAVIGATION SYSTEMS - Controls and Indicators

WX Radar Function Selector (6)

NOTEIntegral light comes on to indicateswitch activated.

OFF - Removes power from system.STBY - Applies power to selected

circuits to warm up thesystem (approx. 3 minutesrequired) and maintain it ina state of readiness.

NORM- Activates total system tosend and receive signalsand display them on thescope.

CONT - The contour position em-phasizes areas of highprecipitation, presenting themas blacked out areas withinthe storm cells.

MAP - Displays local terrain featureson the scope. Should be usedonly with range selector setat minimum range, 50/25.

TEST - Displays a test pattern forsystem checkout withoutradiating energy.

FAULT Lights (2)

Come on to indicate ANT and/or RTunit failure.

WX Radar Antenna TILT Control

Varies the vertical plane of scanningof the outgoing beam by tilting theantenna. Tilt limits are from 15°above to 15o below the fuselagereference plane.

WX Radar Transfer Switch

Selects either transmitter/receiver 1or 2 for operation. The selected unitprovides displays on both scopeswhile the unselected unit is in stand-

by.

WX Radar GAIN Knob

MIN/MAX - Permits manual controlof receiver sensitivity.

AUTO - Automatically controlsreciever sensitivity tosignals of varying in-tensity.

WEATHER RADAR CONTROL PANEL(PEDESTAL)

RANGE & MARKS

Provides five scope range selectionand appropriate range marks for theselected range.

25/5 - Provides 25NM scoperange with 5 NM marks.

50/10 - Provides 50NM scoperange with 10 NM marks.

100/25 - Provides 100NM scoperange with 25 NM marks.

150/50 - Provides 150NM scoperange with 50 NM marks.

300/50 - Provides 300NM scoperange with 50 NM marks.

BRIGHTNESS Control

Adjusts scope displays intensity foroptimum viewing under varying cock-pit lighting condition.

TCAS Display Control Pushbutton

Selects three Weather Radar/TCASDisplay modes. Modes are cycled bypushing momentarily.

WXR/TCAS Auto mode - NormallyWeather is displayed. When TCASissued ТА or RA is removed, displayreverts to Weather indication.

WXR/TCAS Overlay mode - Trafficdisplay always overlays the weatherdisplay.

TCAS Only mode - Only TCASinformation is displayed.

WEATHER RADAR INDICATOR

CAPTAIN'S AND COPILOT'SCONSOLES

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NAVIGATION SYSTEMS - Controls and Indicators

Maximum Range (Blue) Range Marks (Blue)

BackgroundNoise (Green)

Range Marks (Blue)

Green Video Test Band

Green Video Test BandYellow Video Test Band

Red Video Test Band

Yellow Video Test Band

NORMAL WEATHER RADAR TEST PATTERN

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NAVIGATION SYSTEMS - Controls and Indicators

Airway Marker Beacon Light(White)When on indicates airplane is posi-tioned over airway marker beacon.

Middle Marker Beacon Light(Amber)

When on indicates airplane is po-sitioned over a terminal middlemarker beacon.

Outer Marker Beacon Light (Blue)

When on indicates airplane is posi-tioned over a terminal outer markerbeacon.

MARKER BEACON LIGHTS(CAPTAIN'S AND COPILOT'S INSTRUMENT PANELS)

Standby Magnetic Compass

Indicates heading of airplane in rela-tion to magnetic north. Magneticcompass has a stow position.

STANDBY MAGNETIC COMPASS(CENTER WINDSHIELD)

(For description, refer toFlight Instruments Chapter)

TAS/SAT INDICATOR

CENTER INSTRUMENT PANEL

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NAVIGATION SYSTEM - Controls and Indicators

INS Selector (Inoperative on air-planes without INS installed)

NORM - INS 1 and INS 2 providenavigation signals to theCapt's and F/O HSIrespectively when HSIswitch is in INS. INS 1 andINS 2 also provide steer-ing signals to FGS 1 andFGS 2 respectively. No an-nunciator light.

BOTH — INS 1 is providing naviga-ON 1 tion signals to the Capt's

and F/0's HSI (with HSI inINS) and steering signalsto FGS 1 and FGS 2. INSannunciator light on.

BOTH — INS 2 is providing naviga-ON 2 tion signals to the Capt's

and F/0's HSI (with HSIswitch in INS) and steeringsignals to FGS 1 and FGS2. INS annunciator lighton.

Annunciator Lights

Light on indicates selector not inNORM position and switching unithas switched to correct position.

RADIO Selector

NORM-VOR/ILS receivers 1 andVOR/ILS receivers 2provide radio navigation forthe Capt's and F/0's HSIrespectively (HSI switch inRAD) and also the Capt'sand F/0's ADI respectively.No annunciator light.

BOTH-VOR/ILS receivers 1ON 1 provide radio navigation

for the Capt's and F/0'sHSI (HSI switch in RAD)and ADI's. RADIO annun-ciator light on.

BOTH-VOR/ILS receivers 2ON 2 provide radio navigation

for the Capt's and F/0'sHSI (HSI switch in RAD)and ADI's. RADIO annun-ciator light on.

(OVERHEAD PANEL)

DME Indicator (2)

Provides digital readout of nauticalmiles slant range to the selectedDME facility. Blank when data areunusable. Dashes indicate no com-puted data displayed.

DME INDICATORCAPTAIN'S AND COPILOT'S

INSTRUMENT PANELS

NOTE

The INS selector switches INS dis-tance and groundspeed data for theHSI's through the INS switching unit.Normal operation is Captain on 1 andF/0 on 2. The INS annunciator lightcomes on when selector is not in theNORM position and the switching unithas switched to the system selected.

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NAVIGATION SYSTEM - Controls and Indicators

FD CMD Selector

(For description refer toAutomatic Flight Chapter)

(OVERHEAD PANEL)

DME Switch (2)

HSI Switch

CRS Readout (2)CRS Select Knob (2)

HDG ReadoutHDG Control Knob

(For description refer toAutomatic Flight Chapter)

GLARESHIELD

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NAVIGATION SYSTEMS - Controls and Indicators

ILS Test Switch (2)

After selecting an ILS frequency, (a valid sig-nal is not required for ILS test), adjustingcourse to airplane heading, and placing HSIswitch in RAD position; placing ILS test switchto the UP/L position will cause the respectiveHSI navigation fail and GS flags and the ADIGS flags to be in view for a short time and thenbe removed from view. Then the respective HSIcourse deviation indicator moves one dot left,the ADI localizer indicator moves one dot left,and the glide slope pointers on the respectiveHSI and ADI indicators move one dot abovecenterline. If the test switch is held in test po-sition, the flags wi l l reappear indicating thetest cycle is over. The reverse indications willoccur when DN/R position is used.

NOTEILS test inhibited if LOC TRK or GS TRK isannunciated in the FMA's.

MKR BCN Test Button

Pushing the marker beacon test button willcause the airway, middle, and outer markerbeacon lights to come on sequentially. With therespective marker audio switch on the audiopanel turned on, a tone (related to each in-dividual light) will be heard.

VOR Test Button (2)

After selecting a VOR frequency, (a valid sig-nal is not required for VOR test), adjustingcourse to 180 degrees, and placing HSI switchin RAD position; pushing the VOR test buttonwill cause the respective HSI Nav flag to be inview for a short time and then be removedfrom view, the respective HSI course deviationindicator centers, the To indicator appears,and the respective VOR pointers on the RMIindicators indicate 180 degrees. If the testbutton is held in the test position, the flags willreappear indicating the test cycle is over.

DME Test Button (2)

Pushing the DME test button will cause therespective DME indicators to be blank for one se-cond, display all dashes for one second, then dis-play all zeros, and when the test button is releas-ed, revert to the original display.

OVERHEAD PANEL

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NAVIGATION SYSTEMS - Controls and Indicators

GMT Hour Set Knob

When pulled out and rotated(right), the two left GMT (hour)digits wil l update.

Power Indicator

Black-Indicates time system isenergized and GMT min-ute set knob has beenactuated to update time.

RED - Indicates time system isdeenergized, or systemenergized (or power hasbeen interrupted) butGMT minute set knobhas not been actuated toupdate time.

Minute Marker Hand

Records elapsed minutes whenCHRO (short term elapsed time)button is pushed. Moves 12 min-utes in 360 degree sweep.

ELAPS Button

Pushing the ELAPS button startsthe long term digital time in theELAPS window. Pushing theELAPS button again will causethe digital reading in the ELAPSwindow to return to zero.

GMT Readout

Digital presentation of GreenwichMean Time (GMT).

GMT Minute Set Knob

When pul led out and rotated(right), the two right GMT (min-ute) digits will update.

Sweep Second Hand

Records elapsed seconds whenthe CHRO (short term elapsedtime) button is pushed. Moves 1minute in 360 degree sweep.

ELAPS Readout

Shows long term elapsed time inhours and minutes. A green dotwill appear between the hour andminute digits when ELAPS timeis operating.

CHRO Button

Pushing the CHRO button startsthe short term elapsed time asrecorded in minutes (minutemarker hand) and seconds(sweep second hand). Pushingthe CHRO button again will re-turn the minute marker andsweep second hand to zero.

CLOCK (3)(THIRD CLOCK LOCATED

ON F/E'S LOWER PANEL)

CLOCK Button (2)

Pushing the CLOCK button startsthe respective short term elapsedtime (CHRO) as recorded in min-utes (minute marker hand) andseconds (sweep second hand).Pushing the CLOCK button againwill return the minute markerand sweep second hand to zero.

(CAPTAIN'S AND FIRST OFFICER'SINSTRUMENT PANELS)

CAPTAIN'S AND COPILOT'SLIGHT CONTROL PANEL

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NAVIGATION SYSTEM - Controls and Indicators

CHRO Button

Pushing the Chro Button starts theshort term elapsed time as recordedin minutes (Minute Marker) andseconds (Sweep Second Hand).Pushing the Chro Button a secondtime will stop the timer and "freeze"the Minute Marker and Sweep Se-cond Hand. Pushing the Chro Buttona third time will reset the MinuteMarker and Sweep Second Hand to"zero."

GMT Display

Segmented light display of GreenwichMean Time (GMT) in hours, minutesand tenths of minutes.

DIM Control

Controls intensity of GMT andElapsed Time Displays.

NOTE

Dim control can reduce intensity tothe point of extinguishing display,however, timekeeping is maintained.

Sweep Second Hand

Records short term elapsed secondswhen the Chro Button is pressed.Moves 1 minute in 360 degreesweep.

ET Selector

Used to control the long term ElapsedTime Display.

OFF - Resets display to "zero."

RUN - Initiates timekeeping.

HLD - Stops and holds display un-til RUN is re-selected ordisplay is reset to OFF.When RUN is re-selected(from HLD), time will ac-cumulate from the point itwas stopped.

Minute Marker

Records short term elapsed minuteswhen Chro Button is pressed. Moves12 minutes in 360 degree sweep.

GMT Control Knob

Used to set and control GMT

FS - (Fast Set) Updates time atthe rate of one hour per se-cond.

SS - (Slow Set) Updates time atthe rate of one minute persecond.

HLD - (Hold) "Freezes" GMT dis-play.

RUN - Placing control to this posi-tion initiates timekeeping.

TEST - GMT and Elapsed TimeDisplays indicate all 8's.

NOTE

Although the "seconds" are not dis-played, the timekeeping willautomatically start at "zero seconds."

ELAPSED TIME Display

Segmented light display. Displayslong term elapsed time up to 59hours and 59 minutes.

FLIGHT ENGINEER'SLOWER PANEL

This clock is installed on some airplanes.

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NAVIGATION SYSTEM - Controls and Indicators

ВАТТ Light

Comes on red to indicate backup power is lessthan the minimum necessary to operate the INS.If the light comes on, the INS will shut down.Press light cap to test. Both ВАТТ light andREADY NAV light should come on. Press lightcap again to turn off lights.

READY NAV Light

Comes on green when INS Mode Selector is inALIGN position and INS has completed align-ment cycle, indicating mode selector switch maybe moved to NAV. Goes off when NAV modeselected. Press light cap to test. Both READYNAV light and ВАТТ light should come on. Presslight cap again to turn off lights.

INS Mode Selector

OFF - Power removed from INS.

STBY - Power is applied to INS for gyro warmup andautomatic self-leveling of the inertial platform.About one minute after STBY position isselected the ADI ATT flag, HSI HEADING flag,and the RMI OFF flags are removed from view.All waypoints are automatically cleared and anautomatic alignment sequence starts when INSmode selector is moved from OFF to STBYposition. Display test and insertion of aircraft'spresent position are performed with modeselector in STBY position. (Display test mayalso be performed in ALIGN and NAV position).

NOTEAlignment can only be accomplished when air-craft is on the ground and in a static position.After insertion of present position, do not moveaircraft until alignment is completed and NAVposition is selected.

ALIGN - System continues automatic alignment. Totalalignment sequence lasts about 17 minutes.READY NAV light comes on to indicateautomatic alignment is complete and modeselector may be moved to NAV. Waypointsmay be inserted during automatic alignmentsequence.

NAV - Normal operation after automatic alignment iscomplete. INS mode selector is detented inNAV position and must be pulled out beforeselector can be moved from NAV position.

NOTEIf selector is moved from NAV to STBY or ATTREF, the INS must be realigned on the groundwith the aircraft in a static position, beforemoving the selector back to NAV.

ATT REF - Provides attitude reference signals to theFlight Guidance System and the ADI, andazimuth stabilization signals to the compasssystem. INS navigation data not available inthis mode.

When selecting ATT REF position from NAVmode, attitude reference data is available im-mediately. When selecting ATT REF directlyfrom OFF position, valid attitude reference datais available in approximately 3 minutes.

NOTEIf WARN annunciator on CDU comes on whileoperating in NAV mode, INS automaticallychanges to attitude reference mode. If this oc-curs, manual selection of ATT REF position willcause WARN annunciator to go off if attitudereference mode is valid.

Effective on aircraft with Inertial Navigation System installed.

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NAVIGATION SYSTEM - Controls and Indicators

FROM/TO DisplayDisplays FROM waypoint numberand TO waypoint number (Displayis in test configuration)

WPT Selector WheelWhen the data selector is at WPT, theWPT (Waypoint) selector wheel selectswaypoints 1 through 9 for latitude andlongtude insertion, or selects waypoint0 through 9 for presentation ofwaypoint coordinates on left or rightdata display

TK CHG KeyAn integral light in the key comes onwhen the key is pushed to initiate amanual track leg change A light in theINSERT Key comes on at the sametime, to indicate the INS is ready for in-sertion of the new data The TK CHGKey light goes off when the INSERTKey is pushed

AUTO/MAN/RMT Selector

AUTO - Automatically initiates way-point changes

MAN - Permits manual waypointchanges.

RMT -Permits remote loading ofwaypoint coordinates (Simul-taneous loading and insertionof such data into more thanone INS using only one controldisplay panel) Enables remoteranging, and display of XTKoffset FROM/TO Displayflashes

Left Data DisplayDepending on the position of thedata selector, the following will bedisplayedTrue TrackTrue HeadingCross track DistanceLatitudeDistanceWind DirectionDesired Track(Display is in test configuration)

Right Data DisplayDepending on the position of thedata selector, the following will bedisplayedGround SpeedDrift AngleTrack-angle ErrorLongitudeTimeWind SpeedStatus Code(Display is in test configuration)

DIM Selector Wheel

Controls intensity of the displaysWith DIM Wheel set to lowest in-tensity, displays will be blank

Insert KeyWhen pushed (light on) transfersentered data into INS computer

ALERT Light (Amber)

Comes on 90 seconds be-fore each track leg andthen either goes off whena track leg change is auto-matically made or flashesto indicate that a track legchange must be manuallyInitiated.

ВАТТ Light (Amber)Comes on when the INS is operating onbackup battery power

WARN Light (Red)Comes on when a system malfunctionoccurs or, during the alignment mode,flashes to indicate that an incorrectpresent position has been inserted oran INS alignment failure has occurred

KeyboardProvides ten keys (0 thru 9) that areused to enter data into the INS controldisplay panel that are to be insertedinto the INS computer A CLEAR keywill remove entered data if pushedbefore INSERT key is pushed

HOLD KeyPushing the HOLD Key turns on thelight in the key and holds updated pre-sent position in the left and right datadisplays when the Data Selector is inPOS position and unupdated presentposition when selector is in WPT posi-tion, regardless of WPT Selector Wheelposition Updating continues eventhough the coordinates are nek) in thedisplay Pushing key a second timeturns off the light and the displaysagain show the changing current posi-tion When the Data Selector is in DSRTK/STS, pushing the HOLD Key causesmalfunction codes to replace ActionCodes in the right data display

DATA SELECTOR

Causes left and right data displays to displayselected data

TK/GS - Displays true track and groundspeed

HDG/DA - Displays true heading and driftangle The R or L preceding the driftangle readout indicates the drift is tothe right or left of the aircraftheading

ХТК/TКЕ - Displays cross track distance andtrack angle error (in degrees) The Ror L preceding the readout indicatesthat the aircraft track is to the rightor left of the desired track

POS - Displays present position in latitudeand longitude

WPT - Displays latitude and longitude ofthe waypoint corresponding to thedigit on the WPT selector

DIS/TIМЕ - With the AUTO/MAN/RMT selec-tor in AUTO or MAN position, dis-plays distance and time (based onpresent ground speed) between pre-sent position and next selectedwaypoint along the desired trackWith the AUTO/MAN/RMT Selectorin RMT position, displays great-circledistance and time (based on fixedvelocity) between any two waypointsentered in the INS (RemoteRanging), displays total distance andtime (based on present groundspeed) along the flight path betweenthe present position and anyselected waypoint entered m the INS(Remote Flight Plan Ranging), or dis-plays great-circle distance and time(based on present ground speed)from any waypoint to the presentposition (Remote Ingress) In theabove time calculations 512 knots isused if present ground speed is lessthan 10 knots

WIND - Displays wind direction and speed(knots) Displays are valid only if trueairspeed exceeds 150 knots

DSR TK STS - Displays desired track in the leftdata display when INS Mode Selec-tor is in NAV positron (after initialtrack selection) Displays actioncodes and platform alignmentstatus in the right data display IfHOLD Key is pushed, the actioncodes are replaced by malfunctioncodes

TEST - INS test may be performed with themode selector in the STBY, ALIGN,or NAV position The displaysshould show degree signs, decimalpoints, minute signs, and all eightsexcept left digit of right data dis-play is R FROM/TO display showseights, and ALERT, ВАТТ, WARN TKCHG, INSERT and HOLD lights areon

INS CONTROL DISPLAY UNIT (3)PEDESTAL

Effective on aircraft with Inertial Navigation System installed.

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Jun 1/97

NAVIGATION SYSTEM - Controls and Indicators

BELOW G/S Switch-Light (Amber)(2)Switch-light on indicates correctiveaction required due to excessivedeviation below glideslope. Light isaccompanied by aural annunciation,"Glideslope". Pushing the switch-light when airplane is below 1000feet radio altitude and hard alert isnot in progress will inhibit thebelow glideslope alert or will cancelsoft below glideslope annunciations,if activated. The below glideslopeannunciation cannot be cancelledwhen a hard alert is in progress(below 300 feet radio altitude) ex-cept by flying out of the alert zone.

GPWS Light (Red) (2)

Light on indicates corrective actionrequired due to airplane proximityto the ground or not in proper con-figuration for descent Light is ac-companied by aural annunciations,"Whoop, whoop, pull up".

(GLARESHIELD)

GPWS FAIL Light

Light on indicates ground proximitywarning system is inoperative.(F/E UPPER PANEL NO 2)

GND PROXIMITY Test Button

Pushing the test button will causeaural annunciations, "Whoop,whoop, pull up, glideslope", andGPWS lights, BELOW G/S switch-lights and GPWS FAIL light to ac-tivate. Test cannot be initiatedbetween 50 and 1000 feet radioaltitude.

GND PROXIMITY WARN FLAPOVRD Switch

OVRD - Prevents flap up condi-t ion from actuat ingground proximity warningsystem when intentionallylanding with flaps not inlanding configuration. Allother GPWS modes re-main active.

NORM - Ground proximity warningwill activate if flaps arenot extended for landingbelow 200 feet radioaltitude, or if sink rate isexcessive and flaps arenot extended for landingbetween 500 feet and200 feet radio altitude

OVERHEAD PANEL

JL

Aug 1/76 15-30-13/14

NAVIGATION SYSTEMS - Controls and Indicators

(For description refer toAutomatic Flight Chapter)

ATTITUDE DIRECTOR INDICATOR (ADI)

CAPTAIN'S AND COPILOT'S INSTRUMENT PANELS

JLMay 1/76 15-30-01

NAVIGATION SYSTEMS - Controls and Indicators

GND SPEED Readout

Displays current ground speed,

Heading Bug

A moveable index which indicates se-lected heading when controlled by theheading selector knob on the FGSpanel or indicates true/track drift anglewhen controlled by the INS.

NAV Source Annunciator

RAD - Indicates which radio is provid-ing navigational signals to theHSI.

INS - Indicates which inertial naviga-tion system is providing navi-gational signals to the HSI.

Course Deviation Scale

Indicates amount of deviation from thecenterline of the selected course.

ALERT Annunciator

Comes on 90 seconds before each INStrack leg is reached and then eithergoes off when a track leg change isautomatically made or flashes to indi-cate that a track leg change must bemanually initiated.

Compass Card

A rotating card which is oriented tomagnetic north by signals from thecompass system (HSI switch in RAD)or to true north by signals from the INS(HSI switch in INS).

Reciprocal Arrow

Point to the reciprocal airplane headingon the compass card.

TRU/MAG Annunciator

MAG - Indicates HSI switch is in RADposition and the heading underthe lubber line is magneticheading.

TRU - Indicates HSI switch is in INSposition and the heading underthe lubber line is true heading.

MILES Readout

Displays distance as measured betweenthe airplanes present position and thenext selected waypoint.

Course Pointer

Indicates selected course when the HSIswitch is in the RAD position and indi-cates desired track between from andto waypoints when the HSI switch is inthe INS position.

Glide Slope Pointer

The pointer indicates position of glideslope relative to the position of the air-plane.

Course Deviation Indicator

Indicates the position of selected VORcourse or ILS localizer (HSI switch inRAD) or INS desired track (HSI switch inINS) in relation to the airplane's position.

To/From Indicator

To - Indicates that the selected(Displayed) course, if flown, will take the

airplane toward the station.

From - Points toward tail of coursepointer and indicates that theselected course, if flown, willtake the airplane away fromthe station.

Symbolic Airplane

Indicates position in relation to course.

HORIZONTAL SITUATIONINDICATOR (HSI)

CAPTAIN'S AND COPILOT'SINSTRUMENT PANELS

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Jun 1/97