UH-60COMMAND INSTRUMENT SYSTEM

(CIS)

NOTEThe following slides show simulations of the CIS and various flight instruments. The purpose of the simulations are to show how CIS basically functions. These are close approximations only and do not represent exact recreations.

Vertical Situation Indicator (VSI)

Horizontal Situation Indicator (HSI)

Mode Select Panel

FIRST A QUICK REVIEW

VERTICAL SITUATION INDICATOR (VSI)

Go-Around Advisory

VSI COMPONENTSDecision Height Advisory Marker Beacon Advisory

Collective Position Indicator Roll Command Bar Pitch Command BarSphere (Attitude Indicator) Glide Slope Indicator Bank Angle Scale and Index

Inclinometer (Trim Ball) Turn Indicator Roll Trim Knob Pitch Trim Knob

Miniature Airplane

FAIL FLAGSCISP FAILURE

INDICATES LOSS OR UNRELIABLE SIGNAL INDICATION

INDICATES LOSS OF VERTICAL GYRO POWER OR VSI MALFUNCTION

INDICATES LOSS OR UNRELIABLE SIGNAL INDICATOR

Horizontal Situation Indicator (HSI)

HSI COMPONENTS Heading Select Marker Lumber Line Course Set Display

Distance Shutter (KM Only) Compass Card #2 Bearing Pointer (VOR or ADF)#1 Bearing Pointer (Doppler Only) Course Set Pointer To / From Flag

Heading Set Knob Course Deviation Bar Course Set Knob

FAIL FLAGSLOSS OF RELIABLE NAV SIGNAL OR VHF NAV SET FAILURE VISIBLE WHEN A

FAILURE OCCURS IN THE MAGNETIC COMPASS SYSTEM

MODE SELECT PANEL

NOTE: The switches on the HIS/VSI and CIS mode select panels may change state when the caution/advisory panel BRT/DIMTEST switch is set to TEST. The original indications may be restored by pressing the applicable switches.

Directs Long Range NAV Lateral Deviation And NAV Flag Signals To VSIs And HSIs.

Directs VOR Or ILS Signals to VSIs, And HSIs. Provides A Signal To NAV flag.

Reverses the VOR / Localizer Polarity So That The Course Deviation Pointer And Bar Are Pictorially Correct .

Directs FM Homing Deviation And Flag Signals To VSIs.

ALTR CPLT ALTR VORConnects Pilots or Co-Pilots Turn Rate Indicator To Either Their Own Gyro Or The Other Station’s Gyro In Case Their Gyro Fails.Connects Either The Pilot’s or The Co-Pilot’s OBS To The Navigation Receiver. Also Provides Concurrent Connection Of Either The Pilot’s or The Co-Pilot’s HSI Course Datum And Heading Datum Output To The CIS Processor. Defaults To Pilots Side When Power Is Applied. Either Pilot Can “Take Command”.

Connects Pilots or Co-Pilots Sphere (Attitude Indicator) To Either Their Own Gyro or The Other Station’s Gyro In Case Their Gyro Fails.

Connects The #2 Bearing Pointer To The VOR Or The ADF.

VORDLPRILS

BACKCRS

FMHOME

The CIS processes navigational data, aircraft attitude, airspeed, and altitude information appropriate for the mode selected to provide visual command indications for roll, pitch, and/or collective control, as needed, to maintain heading, altitude, and to navigate during enroute and approach operations.

CIS DEFINED

CIS PROCESSOR (CISP) LOCATION

CIS MODE SELECT PANEL

The CIS mode select panel selects one of three modes (Heading, Navigation, or Altitude) of operation to direct navigational signals to the CISP for command signal display.

ON ON ON

Direct Heading And Roll Signals To CIS Processor For Steering Commands That Will Allow Pilot To Maintain A Selected Heading.

Gives Heading Commands To Acquire And Track A Selected VOR, ILS, TACAN, DPLR/GPS Or FM Intercept, Or To Acquire And Track Glide Slope Beam.

Note: If Outside The Capture Zone, Pressing NAV Will Automatically Activate HDG.

Note: If Localizer Frequency Is Entered, HDG and ALT Will Automatically Activate If Outside Capture Zones

Directs Barometric Pressure Signals And Collective Stick Position Signals To CIS Processor. Altitude Hold May Be Activated By Itself Or In Conjunction With HDG And/Or NAV Modes.

ON ON ON

HOW DO YOU USE THE COMMAND BARS AND COLLECTIVE POSITION

INDICATOR?

SIMPLE: They are giving you directional commands that need to be complied with NOW

IMPORTANTThis is Processed Data not Raw Data, thus you maneuver the aircraft until the Bar(s) and/or Collective Position Indicator are centered. There is no intercepting! Adjust PITCH, ROLL and COLLECTIVE until the indicators are centered and continue to make the necessary inputs to keep them centered.

As you see, the Roll Command Bar is to the right, so bank right until the bar is centered.

As you see, the Pitch Command Bar is above the horizon, so pitch the nose up until the bar is on the horizon.

As you can see, the Collective Position Indicator is below the two centering triangles. So again, raise the collective until the indicator is between the two triangles

• Selecting the ALT switch engages the altitude hold mode and couples either the barometric or radar altimeter (depending on sub-mode) to the collective position indicator.

• Altitude hold will engage at the altitude the ALT switch is pressed provided the rate of climb or descent does not exceed 200 feet per minute, altitude is between -1000 feet and +10,000 feet, and airspeed is between 70 and 150 KIAS.

• The CISP provides collective command signals which, if followed, return the aircraft to within ±50 feet of the originally selected altitude.

• When in the level off submode, the altitude hold mode commands collective movement to maintain the absolute altitude selected on the radar altimeter.

ALTITUDE HOLD

ONPush the ALT Button on the CIS Mode Select Panel.

Move the collective down till the indicator is centered. This will start a descent and by moving the collective as necessary to keep it centered will level the aircraft off at the altitude that was referenced.

If you descend below your altitude, the indicator will move down. Again pull up on the collective and keep it centered to climb and level back off.

HEADING MODE• Selecting the HDG mode switch couples the

heading select marker to the roll command bar.

• Signals from the CISP command the roll command bar to deflect in the direction of the required cyclic control input.

• The HDG mode assists in maintaining a turn by providing one degree of roll command for each degree of heading error with a maximum roll command of 20o.

• When properly followed, the command results in not more than one overshoot in acquiring the selected heading and a tracking error of not more than two degrees and will command wings level when the selected heading is reached.

• The HDG mode will automatically turn on if NAV is selected and the aircraft is not within 10°- 20° of the selected course in the VOR NAV mode or within approximately 2.5° of the localizer course in the ILS NAV mode. The HDG mode will then automatically switch off when the aircraft is within 10º- 20° of the selected course in the VOR NAV mode or within 2.5º of the localizer course in the ILS NAV mode.

HEADING MODE (Cont)

ON

Press The HDG Button On CIS Mode Select Panel. Heading Mode Is Activated And The Roll Command Bar Appears And Is Now Slaved To The Heading Marker On The HSI

Now Bank The Aircraft Left Until The Roll Command Bar Is Centered

As The Aircraft Heading Approaches The Heading Selected By The Pilot On The HSI, The Roll Command Bar Now Deflects Right. By Banking Right And Keeping The Roll Command Bar Centered, The CIS Will Roll The Aircraft Onto The Desired Heading

Turn HDG Knob And Move Heading Marker To Desired Heading. Since The Heading is To Our Left, The Roll Command Bar Now Deflects To The Left Telling The Pilot To Turn Left

ON

Uninterrupted

Overhead View

• The initial course interception and the localizer course interception will result in not more than one overshoot at a range of 10 NM at 100 ±10 KIAS and not more than two overshoots at ranges between 5 and 20 NM for airspeeds between 70 and 130 KIAS.

• The collective position indicator when properly followed, will result in not more than one overshoot in acquiring the glide path and have a glide path tracking free of oscillations at an approach airspeed from 130 KIAS down to 50 KIAS.

• Remember that the CISP remains off when the NAV switch is selected unless the DPLR/GPS, VOR, ILS, or FM HOME navigation mode has been selected on the pilot’s HSI/VSI mode select panel.

NAV MODE

• With one of the navigation modes selected (DPLR/GPS, VOR, ILS, or FM HOME) the CIS NAV switch selects the CISP and couples the selected navigation system on the pilot’s HSI/VSI mode select panel (Pilots course deviation pointer) to the roll command bar.

• With a navigation mode selected and NAV ON, the roll command bar displays aircraft turns necessary to track the navigation signal.

• The VOR NAV mode is entered by selecting VOR on the HSI/VSI mode select panel and NAV ON, on the CIS mode select panel.

NAV MODE (Cont)

• If the helicopter position is in excess of 10º- 20° from the selected VOR radial (set in the HSI course set display window), the initial course intersection is made in the heading mode (HDG ON) until the helicopter is within the capture zone.

• When the helicopter is within the capture zone, the CISP commands the heading mode to automatically drop out, and commands a 45º intercept to the selected VOR course (HSI course set display window).

• The capture zone for VOR is within 10º- 20° of the selected VOR course.

• When passing over the VOR station, the CISP reverts to a Station Passage Sub-Mode for 30 seconds. Cyclic roll commands during this mode will be obtained from the HSI Course Datum signal.

NAV MODE (Cont)

> 12 KM

12 to 2 KM

< 2 KM

1000 Meters

1000 Meters

1000 - 200 Meters

1000 - 200 Meters

200 Meters

200 Meters

Capture Zones: Long Range Navigation (LRN) Mode

ACP(Doppler NAV Mode)

Capture Zones: VOR NAV Mode

10o -

20o

10o -

20o

Capture Zones: ILS NAV Mode

Localizer / Localizer Back Course

.5o

.5o

2.5o

2.5o

Glide Slope - (After Glide Slope Interception)

NOTEThe next slide shows a simulation of the NAV Mode. The purpose of the simulation is to show how CIS basically functions. Although The Course Deviation Pointer is not shown on the VSI, the Course Deviation Pointer would be visible and responding as does the Course Deviation Bar in the real aircraft. Include the Course Deviation Pointer to all references in the next slide regarding the Course Deviation Bar.

Start A Right Turn And Keep The Roll Command Bar Centered Through Roll Out

ON

22

1

1

VOR

VOR

ON

ATC: “Army 12345, Turn Right To 135 Degrees And Intercept The 060 Course To The Wiregrass VOR, Then Resume Own Navigation. “

Turn HDG Marker to 135 Using the HDG Knob

Enter Appropriate VOR Frequency Then Select VOR

Course Deviation Bar Deflects To The Right

Select VOR For The #2 Bearing Pointer

Enter 060 Into The Course Window Using The CRS Knob

Press NAV Switch

HDG Mode Automatically Engages And Roll Command Bar Comes Into View And Deflects To The Right Since Outside The VOR Capture Zone

The Head Of The #2 Bearing Pointer Is Now Being Pushed To The 060 Course

Within Capture Zone: Course Deviation Bar Starts To Move, HDG Mode Automatically Disengages And Roll Command Bar Deflects Left To Position Aircraft For A 45 Degree Intercept. Continue To The Follow Roll Command Bar

Now On A 45 Degree Intercept

ON

22

1

1

VOR

VOR

ON

Uninterrupted

Heading Of 060o

Right Turn To 135o

Within The VOR Capture Zone. Turn To The Left To Intercept Course At A 45o Angle

Interception Of Course 060o With No More Than One Over Shoot

Overhead View

NOTEAlthough the preceding simulation used a VOR for Navigation, the same indications would be observed if the Mode Select panel was in the DPLR mode. The only difference would be the capture zones as shown earlier.

• ILS NAV mode is entered by selecting ILS on the HSI/VSI mode select panel and NAV ON on the CIS mode select panel. Intercepting the localizer course is done in the same manner as the previous NAV mode simulation. Except the Capture Zone is 2.5o vs. 10°- 20°.

• With the ILS NAV mode selected, the Pitch Command Bar is coupled to the airspeed indicated on the airspeed indicator at the time NAV is selected.

• This provides a limited cyclic pitch command which when followed properly, results in maintaining an airspeed that should not deviate more than 5 knots from the IAS existing at the time the ILS NAV mode was engaged.

ILS NAVMODE

• During ILS NAV mode the barometric altitude and collective stick position signals are processed to provide a limited collective position indication, which when followed causes the helicopter to maintain the altitude existing at the time the ILS NAV mode is engaged.

• During an ILS approach, when the helicopter enters the localizer capture zone, the HDG ON mode automatically disengages.

• The APPROACH mode, a Sub-Mode of the ILS NAV mode, will be automatically engaged when the helicopter captures the glide slope.

• When the glide slope is intercepted during the Approach mode, the ALT ON mode automatically disengages.

• The cyclic roll commands are limited to ±15° during the Approach mode.

ILS NAV MODE (Cont)

ON

22

1

1

VOR

ILS

ON

ILS NAV Mode

Intercepting and tracking the Localizer Course is the same as intercepting and tracking the VOR course in the previous simulation. There are some differences in regards to instrument indications however…

ON

“ILS” Will Illuminate When A Localizer Frequency Is Entered

ADF

Number #2 Bearing Pointer Is Inop When VOR Is Selected And A Localizer Frequency Is Entered. If A LOM Is Available, Select ADF

When NAV Switch Is Pressed, ALT Switch Illuminates Along With The HDG Switch If Outside The Capture Zones

#2 Bearing Pointer Now Points To The LOM. Upon Station Passage It Will Swing 180 Degrees

The Pitch Command Bar Will Come Into View And Provide Commands That Will Maintain Airspeed When Kept Centered Using Fore And Aft Cyclic Inputs

In-Addition, The Collective Position Indicator Also Comes Into View And When Followed, Will Maintain Altitude Until Glide Slope Interception

Push Forward On the Cyclic To Center The Pitch Command Bar. This Will Increase Your Airspeed To What Was Referenced When The NAV Button Was Pushed

As You See, We Have Pitched The Nose Up And Now The Pitch Command Bar Has Moved Below The “Miniature Airplane”, Indicating Our Airspeed Has Slowed

ONON

We Are Executing An ILS Approach. We Are Centering The Roll And Pitch Command Bars And Are Tracking Inbound On The Localizer. We Are Now Approaching The Glide Slope…

The Glide Slope Indicator Appears And Moves Down The Scale As The Aircraft Approaches The Glide Path

The Collective Position Indicator Is Now Slaved To The NAV And Is Coupled To The Glide Slope

The ALT Hold Function Deactivates

If We Allow The Aircraft To Go Above The Glide Slope We Get The Following Indications. The Collective Position Indicator Is Telling Us To Lower The Collective

By Centering The Collective Between The Centering Triangles and Keeping The Collective Centered, The Aircraft Will Intercept and Stay On Glide Path

APPROACH MODE

ONON

UNINTERUPTED

Go Around Mode

Press Go Around Button on Cyclic

Roll Command Bar provides zero degree bank angle

Note: 5 Seconds After GA Button Pressed

*

*

• The Level-Off Mode will be activated when either the VOR NAV or ILS NAV modes are engaged and will be deactivated by selection of another mode or when a radar altitude valid signal is not present.

• This mode is automatically engaged when the radar altitude goes below either the pilot’s or copilot’s radar altimeter low altitude warning bug setting, whichever is at the higher setting.

• A DH legend on the VSI and a LO light display on the radar altimeter indicator goes on whenever the radar altitude is less than the LO bug setting.

Level Off Mode

Level Off Mode (Cont)

• When properly followed, will cause the helicopter to maintain an altitude within 10 feet of the low altitude setting for settings below 250 feet and 20 feet for settings above 250 feet.

• During ILS or VOR approaches, the barometric altimeter must be used to determine arrival at the minimum altitude. Radar altimeter setting SHALL NOT be used for level off commands in the VOR NAV/ILS NAV modes because variations in terrain cause erroneous altitude indications.

• The FM HOME mode couples FM homing signals from FM #1 to the NAV systems.

• The FM HOME mode is engaged by turning on FM #1 and selecting the HOME function on the control box.

• In order for the FM HOME mode to be engaged, the ILS mode select light must not be lit (ILS deselected), and the FM HOME light must be illuminated and the NAV switch on the CIS mode select panel must be set to ON.

• The CISP sends these FM homing signals to the VSI only. The signals from the CISP are applied to the VSI Deviation Pointer, Roll Command Bar and Navigation Off Flag.

FM HOMING

Rule of 5(1) There are five rules that apply to the HSI/VSI indicators in

the UH60 helicopter.

(2) These rules are referred to as the "Rule of 5“

Rule #1: The #1 Bearing pointer is slaved to the Doppler/GPS only.

Rule #2: The #2 Bearing pointer can have one of two inputs, either from VOR or ADF.

Rule #3: The Course Deviation Bar (HSI) can have one of three inputs, either Doppler/GPS, VOR, or Localizer.

Rule #4: The Course Deviation Pointer (VSI) can have one of four inputs, either Doppler/GPS, VOR, Localizer, or FM Home.

Rule #5: The Roll Command Bar on the VSI can have one of five inputs, either Doppler, VOR, Localizer, FM Home, or Heading.

Refer To Your Student Handouts And TM 1-1520-253-10, Chapter 2

For More Detailed Information

QUESTIONS