Outline
• Block Diagrams
• Line Replaceable Unit Concept
• Aircraft Instrumentation
• G1000 Components Explained
• Failure Operations
• Emergency Power Distribution (C172 NAV III)
• Alerts (C172 NAV III & DA42 L360)
-Some aircraft in the fleet are NOT equipped with GDU 1044B displays or GFC 700 Flight Directors.
-This diagram applies to both the C172 and the DA-42 L360. .
Garmin 1000 Optional Equipment
-Select ERAU C172 Nav IIIs are equipped with GDL 69A
Data Links.
*The XM subscriptions in these aircraft are not
maintained.
-All C172 Nav IIIs are equipped with “CO Guardian” carbon
monoxide detectors. -406 MHz ELTs utilize GPS derived position information from GIA #1. -Other optional equipment is not installed in ERAU G1000 equipped aircraft.
Line Replaceable Units
• Each box on the above block diagrams are considered line replaceable
units (LRUs).
• LRUs allow for the removal and reinstallation of equipment by
maintenance in a fraction of the time it would take to replace/repair
traditional equipment.
• LRUs also allow for the manufacturer to mount various components
behind the displays or in remote locations in the aircraft, based upon
need.
• The following slides demonstrate the removal of an LRU. *
(They do not represent the location of LRUs in the C172 or DA42-L360)Aft Avionics Bay Behind MFD Left Wing GIA 63 #2 COM2 NAV2 GPS 2 GTX 33 Mode S XPDR w/ TIS GIA 63 #1 COM1 NAV1 GPS 1 GRS 77 AHRS GMU 44 Magnetometer GMA 1347 GDU 1040 #1 (PFD) GDU 1040 #2 (MFD) Cockpit GEA 71 Engine Airframe
Interface GDC 74AADC
Cessna
172S
Nav III
Aft Avionics Bay Cockpit GIA 63 #2 COM2 NAV2 GPS 2 GTX 33 Mode S XPDR w/ TIS GIA 63 #1 COM1 NAV1 GPS 1 GRS 77 AHRS GEA 71 Engine Airframe Interface GMA 1347 GDU 1040 #1 (PFD) GDU 1040 #2 (MFD) GMU 44 Magnetometer GDC 74A ADC Behind PFD Right Wing Tip
Behind Engine Compartment
Diamond
DA-42 L360
Round Dial Vs. G1000
Airspeed Altitude
Attitude
DG/HSI
Airspeed Indicator
Markings – Airspeed markings are the
same as those depicted on a round dial airspeed indicator.
Trend Vector – The end of the trend vector
displays approximately what airspeed will be reached in 6 seconds if the current rate of acceleration is maintained. This is displayed as a magenta line up and down the airspeed indicator.
Attitude Indicator
Pitch Graduation – Displayed
in 2.5º increments.
Bank Graduation – Major tick marks at
30º and 60º and minor tick marks at 10º, 20º, and 45º are shown to both the left and right of zero.
Unusual Attitude Recovery
• Chevron Display
– Nose High 50º
– Nose Low –30º
• De-clutter
– Nose High 30º
– Nose Low –20º
– Bank 65º
Altimeter
Trend Vector – The end of the trend
vector displays approximately what altitude will be reached in 6 seconds if the current rate of vertical speed is maintained.
Altitude Graduation – 20ft
increments with numeric labels every 100ft.
Barometric Setting Box
Altitude Bug Metric Display
Vertical Speed Indicator
Vertical Speed Graduation – Numbered
labels are displayed in 1000’ increments. The Vertical Speed Pointer displays the current vertical speed when the rate exceeds 100fpm.
Vertical Speed Pointer
Horizontal Situation Indicator
HSI – Displays heading information
overlaid with navigation information to enhance horizontal situational awareness.
Tick Marks – Located at 45º
intervals to aid in establishing intercept angles.
Current Track Indicator
Navigation Source
Turn Rate Trend Vector Slip/Skid
Turn and Slip
Turn Rate Indicator–
Displays half-standard rate and standard rate turns. Rates greater than 4 deg/sec are depicted by an arrowhead.
Slip/Skid –
One slip/skid indicator
displacement is equal to one ball displacement on a traditional slip/skid indicator.
Primary Flight Display (PFD)
&
Multi-Function Display (MFD)
PFD/MFD
• Both Displays are identical in hardware.
• The aircraft wiring harness determines whether the
display functions as a PFD or an MFD.
• An Ethernet-based, high speed digital data-bus ties the
display units and integrated avionics units together.
Right side
• COM VOL/SQ
• COM Frequency Transfer key
• COM Frequency Selector
• Course and Baro Selector
• Range/Pan Joystick
• Direct-To, Flight Plan, Clear, Menu, Procedures, and Enter keys
• Flight Management System (FMS)
Left side
• NAV VOL/SQ
• NAV Frequency Transfer key • NAV Frequency Selector • Heading Selector
• Altitude Selector
PFD/MFD Bezel Controls
Secure Digital Memory Cards
Bottom Slot
Supplemental Data Card Databases:
• Expanded Basemap • Terrain
• Airport Terrain • Obstacles • Safe Taxi
• Airport Directory (AOPA)
• FliteCharts or ChartView (MFD Only)
Top Slot Used For:
•Importing/Exporting Flight Plans •Flight Data Logging
Primary Flight Display (PFD)
• Additional information on PFD
– Top
• Nav frequency window
• Com frequency window
• Waypoint status window
• Autopilot annunciation
– Bottom
• Inset Map
• Outside Air Temperature
• Transponder window
• System time
Primary Flight Display (PFD)
Soft Keys
• Additional information on PFD
– Soft keys
• INSET - Moving map inset options
• PFD - PFD configurations and bearing pointers
• OBS - GPS manual sequencing and course selection
• CDI - Selects HSI navigation source
• XPDR - Transponder code and mode selection
• IDENT – Transponder ident function
• TMR/REF - Reference speeds and timer function
• NRST - List of nearest airports
Multi-Function Display (MFD)
Page Group Icon
E ng in e G au ge s
NAV frequencies COM frequencies
Waypoint Status Bar
Multi-Function Display (MFD)
Page Group Icon
The Page Group Icon shows which page group and active page is
being viewed.
Page Groups:-Map
-Waypoint -Auxiliary -Flight Plan -Nearest
Multi-Function Display (MFD)
Map Page Group
Navigation Map Traffic Map Stormscope®
Terrain Proximity / TAWS-B Weather Data Link (Optional)
Multi-Function Display (MFD)
Waypoint (WPT) Page Group
Airport Information Pages:
-Airport Information -Airport Directory -Departure Information -Arrival Information -Approach Information -Weather Information
Intersection Information NDB Information
Multi-Function Display (MFD)
Aux Page Group
Trip Planning Utility GPS Status
Multi-Function Display (MFD)
Flight Plan Page Group
Multi-Function Display (MFD)
Nearest Page Group
Nearest Pages
-Airports
-Intersections
-NDBs
-VORs
-User Waypoints
-Frequencies
-Airspaces
Audio Panel
Audio Panel
• The digital audio panel features controls for three (3) major function groups:
– Communications – Navigation
– Intercom System (ICS)
• Intercom Volume and Manual Squelch Controls are also on the panel.
• Fail-Safe Operation
– A fail-safe circuit connects the pilot’s headset and microphone directly to COM1 in the event power is interrupted or the unit is turned off. Digital performance is no longer available resulting in analog operation.
• Reversionary Mode
– Pressing the DISPLAY BACKUP button activates/deactivates reversionary mode.
Marker Beacon Receiver Controls
Audio Panel
• Split Com Function
– Split COM performance varies significantly across installations and is affected by both the distance between the antennas and the separation of the tuned frequencies.
• Split COM operations are NOT authorized and are disabled in the Cessna 172 NAV III and DA-42 L360.
• Marker Beacon Receiver
– The marker beacon receiver is integrated into the audio panel.
– Beacon receiver arm/mute/disarm and High Sense controls are located on the panel.
• It is recommend the receiver be operated in low sense during ILS operations.
Marker Beacon Indications
Outer Marker Middle Marker
Integrated Avionics Unit
Integrated Avionics Unit
• Communications hubs for the system
– Primary communications paths for system components to the PFD and MFD.
– This provides for a high level of system
redundancy and integrity as data is cross-checked to ensure proper system operation.
• Avionics housed within the each unit include:
– VHF COM Transceiver – VOR/Localizer Receiver
– GPS Receiver (WAAS upgrade if installed) – Glide Slope Receiver
– System Integration Processor
**See the G1000 LRU diagrams for LRU
interfacing with the Integrated Avionics
Units.
Integrated Avionics Units
Integrated Avionics Units
DA42-L360: Avionics Bay Looking Through Back Door Under Baggage Compartment
Front
of
Aircraft
Air Data Computer
Air Data Computer
• Inputs include:
– Pitot – Static
– Outside Air Temperature
• Produces:
– Airspeed Indicator – Altimeter
– Vertical Speed Indicator – Outside Air Temperature – True Airspeed
– Other E6B type calculations provided within MFD pages.
• Designed Operating Range:
– Altitude -1,400 ft to 55,000 ft – IAS up to 430 knots
– Operates -55oC to +70oC • Accuracy supports RVSM
Air Data Computer
C172: Behind Avionics Bay Cooling Fan. Picture Taken From Behind Avionics Bay
Front
of
Aircraft
Air Data Computer
DA42-L360: Behind PFD
Front
of
Aircraft
Outside Air Temperature Probe (GTP)
Attitude Heading Reference
System (AHRS)
Attitude Heading Reference System
• Produces:
– Attitude Indicator
– Heading/HSI
– Slip/Skid
• Solid state component utilizing
MEMS technology.
• Alignment can occur in as little as 1
min even while the aircraft is
taxiing.
• In-air dynamic restarts can occur at
bank angles up to 20º.
• Inputs from GPS, GDC, and GMU
are used as reference to enhance
performance and integrity.
– Failure of the AHRS will occur before
any hazardous or misleading
information is displayed.
Attitude Heading Reference System
• Micro Electro-Mechanical
System (MEMS)
– MEMS technology
determines attitude by
measuring changes in
vibration through tiny
elements.
– When an acceleration occurs
in any of the three axis of
rotation, the vibration
frequency changes slightly
which induces a voltage that
can be measured as a change
in pitch, bank or yaw.
Attitude Heading Reference System
• External Inputs (GDC, GPS, GMU):
– The AHRS is not totally self-sufficient and must have GPS input
or both the Magnetometer and the ADC to consider itself reliable.
– If the AHRS does not have sufficient inputs to cross-check itself,
or if it does detect an error, it will flag itself as unreliable and
display red-X “ATTITUDE FAIL.”
– A gyroscope, whether physical or electronic, must be referenced
to something in the real world. That is, a gyroscope must have an
erecting mechanism.
• The G1000 AHRS maintains its alignment primarily by using GPS and
ADC-determined flight path information.
• The AHRS also uses the vertical component of the magnetometer’s
output to correct pitch.
Attitude Heading Reference System
C172: Behind Avionics Bay Cooling Fan. Picture Taken From Behind Avionics Bay
Front
of
Aircraft
Attitude Heading Reference System
Front
of
Aircraft
Magnetometer
Magnetometer
• Senses the Earth’s magnetic
field information and measures
both the vertical and horizontal
components.
• Data is sent to the AHRS for
processing.
Magnetometer
Mode S Transponder
Mode S Transponder
• Features:
– Solid-state unit requiring no warm-up time.
– Automatically transitions to ALT reporting mode at a ground speed of 30kts.
• Interrogation/Reply Capability:
– Mode S
• Provides data-link capability allowing for the reception and presentation (if selected) of airborne traffic, using the FAA-provided TIS (Traffic Information Service) system within a 55 mile radius of select ground sites. • ERAU aircraft are equipped with and present traffic
information through the use of ADS-B and TIS-B which does NOT rely on Mode S transponder input.
– Mode C – Mode A
Mode S Transponder
Mode S Transponder
Front
of
Aircraft
Engine/Airframe Unit
Engine/Airframe Unit
•
Main processing unit for all engine
instrumentation and airframe data.
•
Input Capabilities:
– Manifold Pressure/Engine RPM
– Oil Temp/Pressure
– EGT/CHT on all cylinders
– Electrical System Data
– Fuel System Data
– Vacuum System Data
– Airframe Data
•
The Engine Indication System
(EIS) may also produce
annunciations associated with cabin
and baggage doors.
C172: Located behind MFD
Engine/Airframe Unit
Left Engine GEA
Right Engine GEA
ADS-B Datalink Transceiver
ADS-B Data Link
• Transmits, receives and decodes
Automatic Dependant
Surveillance-Broadcast (ADS-B) and Traffic
Information Service-Broadcast
(TIS-B) traffic information.
• Incorporates a WAAS GPS receiver
(TSO-C145a).
• Transmits/Receives through two
Universal Access Transceiver
(UAT) antennas.
• Interfaces through GIA #2.
ADS-B Data Link Antennas
WAAS GPS Receiver Antenna
Automatic Dependant
Surveillance-Broadcast (ADS-B)
• Purpose
– Information produced by ADS-B and TIS-B is intended to enhance a pilot’s visual acquisition of nearby aircraft and NOT in place of
acknowledging traffic advisories by ATC without visual acquisition or for initiation of avoidance maneuvers.
• Utilizes GPS positioning to transmit:
– Aircraft Position – Velocity
– Projected Track – Altitude
– Flight Identification
• Data Link Capable of Receiving:
– ADS-B information from other ADS-B equipped aircraft and Ground Based Transceivers (GBTs) – TIS-B
– FIS-B
XM Satellite Data Link
XM Satellite Data Link
• Provides XM Satellite Weather
and XM Satellite Radio®
entertainment services.
• The GDL 69A is interfaced
directly with the MFD and
displays graphical weather
information on the MFD and PFD
inset map.
*The XM WX Satellite Weather subscription must be maintained.
*Do not utilize XM Weather information to penetrate hazardous weather.
*Only a handful of C172 are equipped with the GDL 69A and the XM subscriptions are not maintained.
XM Satellite Data Link
Autopilot
Autopilot
• The autopilot utilizes
information from:
– AHRS (Heading)
– ADC (Altitude)
– GIA2 (NAV/LOC/GP/GPS)
– Turn Coordinator (Turn Rate)
• This turn coordinator is located behind the instrument panel and is not visible to the pilot.
• The autopilot is linked to
the system through GIA
#2.
*
See KING KAP 140 supplemental in POH for operational guidance.C172: Turn Coordinator Located Behind Instrument Panel
Autopilot
DA42-L360: Turn Coordinator Located Behind Instrument Panel
Front
Of
Aircraft
Cooling Fans
Cessna 172 NAV III
DA42-L
Cooling Fans
• The C172 system contains four cooling fans:
– Display cooling fan behind PFD and MFD.
– Avionics bay cooling fan in baggage compartment.
– Instrument panel cooling fan in dash.
• The DA42-L360 system contains three cooling
fans:
– Display cooling fan behind PFD and MFD.
– Avionics bay cooling fan.
Cooling Fans
PFD/MFD Display Cooling Fans
Cooling Fans
Front
of
Aircraft
System Failure Indications
GIA 63 GDC 74A GRS 77 GDC 74A GDC 74A GTX 33/GIA 63 GRS 77 No. 1 GIA 63 GIA 63 GDC 74A GEA 71/GIA 63 GIA 63 No. 2 GIA 63 No. 1 GIA 63 No. 2 GIA 63PFD/MFD Failure
•
Single Display Failure
– If one display fails, the primary flight instruments and Engine
Indication System (EIS) are displayed on the remaining screen.
This operation mode is called “Reversionary Mode.”
– The onside radio of the failed display will automatically tune to
121.5.
– The failed GDU’s associated Integrated Avionics Unit (GIA) will
also be lost.
•
Dual Display Failure
– Both radios automatically tune to 121.5.
– The audio panel is subsequently lost and the pilot’s headset
connected to COM 1 through a fail-safe circuit.
PFD/MFD Failure
Reversionary Mode
• The system will
automatically detect a
display failure and initiate
reversionary mode.
• The DISPLAY BACKUP
button can also be pressed
to manually initiate
Audio Panel Failure
• A fail-safe circuit connects the pilot’s headset and microphone
directly to COM1 in the event power is interrupted or the unit is
turned off. Digital performance is no longer available resulting in
analog operation.
• Intercom communications will be lost.
• Stuck PTT
– If the push-to-talk (PTT) key becomes stuck, the COM
transmitter stops transmitting after 35 seconds of continuous
operation. An alert appears on the PFD to advise the pilot of a
stuck microphone.
Air Data Computer Failure
• Presentation of the airspeed, altitude, vertical speed,
OAT and TAS display a red “X”.
• If the OAT probe fails, a red “X” appears both on the
TAS box and the OAT box.
– Pressure altitude reporting for the transponder is lost (Mode
C) and only Mode A capabilities are available.
• Associated ADC instrumentation will still be displayed
in the event of a Pitot-Static system blockage.
• The KAP 140 autopilot will not operate in vertical
speed, altitude capture, or altitude hold modes.
Attitude Heading Reference System
Failure
• If improper operation is detected when compared to
other aircraft sensors (GPS, ADC, Magnetometer) all
attitude and heading presentations are removed and
replaced with a red “X” and the words “Attitude Fail”.
• Failure indications are designed to display before
Hazardous or Misleading Information (HMI) is
presented.
• The KAP 140 autopilot will only operate in Roll
Mode.
Attitude Heading Reference System
Failure
Attitude Heading Reference System
Failure
Magnetometer Failure
• Loss of the Horizontal Situation Indicator
(HSI), heading information, and the turn rate
trend-vector will occur if the magnetometer
fails.
Integrated Avionics Unit Failure
• Single Unit Failure
– The associated COM/NAV/GPS receiver data is no longer available.
– The pilot should tune and select the COM and VHF NAV receiver on the operative GIA unit.
– The operative GPS receiver will automatically take over any active GPS navigation. **Failure of GIA#2 will result in the loss of the GDL 90, KAP 140 Autopilot, and
“CO Guardian” Carbon Monoxide Detector (C172 Only).
• Dual Unit Failure
– The transponder (GTX), engine/airframe unit (GEA), and clock will be lost in addition to both GIA unit associated COM/VHF NAV/GPS receivers.
– The ADC and AHRS will provide data directly to the GDUs through backup paths.
• Failure of the Ethernet High-Speed Data Bus between the PFD/MFD will
result in the inability for a GDU to communicate with the opposite GIA.
Integrated Avionics Unit Failure
Dual GIA Failure
Note the Transponder (GTX) and Engine Airframe Unit (GEA) failure associated with the dual GIA failure.
Transponder Failure
• Transponder failure will not affect any other
LRU.
• A red “X” will be displayed over the
transponder window on the PFD.
Engine/Airframe Unit Failure
• A GEA unit failure will result in the loss of all
engine/airframe data.
– Due to the DA42-L360 having two GEAs only the onside
data will be lost in the event of a single GEA unit failure.
• A much more likely scenario would be one in which
an individual probe or sensor fails. In this case the
individual indication would display a red “X”.
Engine/Airframe Unit Failure
System Status
• LRU Status information can be
accessed through the MFD’s
Auxiliary chapter, System
Status page.
• Checkmark: Active LRUs
• Red X: Failed LRUs
• Pertinent database information
is also displayed.
ANN TEST – Causes an annunciation test tone
to be played and all audio panel lights to illuminate
Emergency Power Distribution
Emergency Power Distribution
• The standby battery will provide at least 30 mins of power
to the essential bus provided the battery is fully charged.
• Essential Bus Components:
– Standby Battery
– PFD
– EIS
– AHRS
– ADC
– COM 1 Transceiver
– NAV 1 (VOR/LOC/GS/GPS) Receivers
– Standby Instrument Back Lights
Standby Battery Behind PFDAlerts
Cessna 172 NAV III
&
Alert Definitions
• Warnings (Red)
• Caution (Yellow)
• Message Advisory (White)
• Aural Warnings (Tone or Voice)
• Soft-Key Function:
– Warning: Press soft-key to acknowledge,
silence tone, and read.
– Caution: Press soft-key to acknowledge and
read
– Advisory: Press soft-key to read, scroll with
FMS knob.
Warnings
C172 NAV III • CO LVL HIGH • HIGH VOLTS • LOW VOLTS* • OIL PRESSURE • PITCH TRIM** DA42 L360 • AP TRIM FAIL • DOOR OPEN • L/R ALTN FAIL • L/R FUEL PR HI • L/R FUEL PR LO • L/R OIL PRES • L/R STARTER*Aural tone is inhibited while the aircraft is on the ground.
**KAP 140 installations only. No aural tone will occur.
• Produces a continuous tone
requiring acknowledgment
by the pilot.
• Visual annunciator is
displayed next to the
Vertical Speed Indicator on
right side of PFD.
• Press alert soft-key to
acknowledge alert.
Cautions
C172 NAV III
• LOW FUEL L
• LOW FUEL R
• LOW VACUUM
• STBY BATT
DA42 L360
• L/R AUX FUEL E
• L/R FUEL LOW
• L/R VOLTS LOW
• PITOT FAIL
• PITOT HT OFF
• STAL HT FAIL
• STAL HT OFF
• STICK LIMIT
• Produces a single tone.
• Visual annunciator is
displayed next to the
Vertical Speed Indicator
on right side of PFD.
• Press alert soft-key on
PFD to acknowledge
alert.
Advisories
System Message Advisory Categories
• PFD & MFD • Database
• GMA (Audio Panel)
• GIA (Integrated Avionics) • GEA (Engine/Systems) • GTX (Transponder) • GRS (AHRS) • GMU (Magnetometer) • GDL (Data-link) • GDC (ADC) • Misc
• No tone is produced.
• Alert soft-key will flash,
requiring pilot
acknowledgement.
• Reference the G1000
Cockpit Reference
Guide (CRG) for
advisory explanation.
References
• AIM
• Cessna 172 NAV III – Information Manual
• Cessna 172S NAV III – An Advanced Pilot’s Guide • Diamond DA42 L360 – Airplane Flight Manual • G1000 Cockpit Reference Guide
• G1000 Guide for DPE/CFIs • G1000 Pilot Guide
• Nasiri, Steven. “A Critical Review of MEMS Gyroscopes Technology and Commercialization Status.” InvenSense. 26 Oct. 2008.
<http://www.invensense.com/shared/pdf/MEMSGyroComp.pdf >
• McClellan, J. Mac. “Garmin G1000 Ignites a New Passion.” Jan. 2004. Flying Magazine. http://www.flyingmag.com/avionics/358/garmin-g1000-ignites-a- new-passion.html
• White, Elecia, and Jose A. Rios. “FAA Certification of a MEMS Attitude and Heading Reference System.” Crossbow Technology, Inc.
