Garmin | GFC™ 600 Digital Autopilot | Garmin GFC™ 600 Digital Autopilot GFC600 Maintenance Manual Part 23 AML STC

Garmin GFC™ 600 Digital Autopilot GFC600 Maintenance Manual Part 23 AML STC
GFC 600
Automatic Flight Control System
Part 23 AML STC Maintenance Manual
Includes Instructions for Continued Airworthiness
for STC SA01844WI
190-01938-00
2017 - 2019
Revision 6
© Copyright 2017 - 2019
Garmin Ltd. or its subsidiaries
All Rights Reserved
Except as expressly provided herein, no part of this manual may be reproduced, copied, transmitted,
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Garmin International, Inc.
1200 E. 151st Street
Olathe, KS 66062 USA
Telephone: 913.397.8200
www.garmin.com
Garmin (Europe) Ltd.
Liberty House, Bulls Copse Road
Hounsdown Business Park
Southampton, SO40 9RB, UK
Phone: +44 (0) 23 8052 4000
Fax: +44 (0) 23 8052 4004
Garmin AT, Inc.
2345 Turner Rd., SE
Salem, OR 97302 USA
Telephone: 503.581.8101
RECORD OF REVISIONS
Revision Revision Date
Description
4
08/16/18
Updates to include VNAV
5
10/12/18
Updated to include dual switches
6
07/18/19
Updated in include GTA and new SW features
DOCUMENT PAGINATION
Section
Table of Contents
Section 1
Section 2
Section 3
Section 4
Section 5
Section 6
Section 7
Section 8
Section 9
GFC 600 AFCS Part 23 AML STC Maintenance Manual
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Pagination
i – vi
1–4
5– 9
10 – 10
11 – 17
18 – 23
24 – 30
31 – 32
33 – 39
40 – 56
Page i
Revision 6
INFORMATION SUBJECT TO EXPORT CONTROL LAWS
This document may contain information which is subject to the Export Administration
Regulations (“EAR”) issued by the United States Department of Commerce (15 CFR, Chapter
VII Subchapter C) and which may not be exported, released or disclosed to foreign nationals
inside or outside the United States without first obtaining an export license. A violation of the
EAR may be subject to a penalty of up to 10 years imprisonment and a fine of up to $1,000,000
under section 2410 of the Export Administration Act of the 1979. The preceding statement is
required to be included on any and all reproductions in whole or in part of this manual.
WARNING
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California to cause cancer, birth defects, or reproductive harm. This Notice is being provided in
accordance with California's Proposition 65. If you have any questions or would like additional
information, please refer to our web site at www.garmin.com/prop65.
WARNING
Perchlorate Material – special handling may apply, Refer to www.dtsc.ca.gov./hazardouswaste/
perchlorate.
IMPORTANT
All screen shots used in this document are current at the time of publication. Screen shots are
intended to provide visual reference only. All information depicted in screen shots, including
software file names, versions and part numbers, is subject to change and may not be up to
date.
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Revision 6
TABLE OF CONTENTS
PARAGRAPH
PAGE
1. INTRODUCTION .................................................................................................................... 1
1.1
Content, Scope, Purpose ................................................................................................. 1
1.2
Applicability ...................................................................................................................... 1
1.3
Organization..................................................................................................................... 1
1.4
Definitions/Abbreviations ................................................................................................. 2
1.5
Reference Publications .................................................................................................... 3
1.6
Revision and Distribution ................................................................................................. 4
1.7
Garmin Technical Support ............................................................................................... 4
2. SYSTEM DESCRIPTION ....................................................................................................... 5
2.1
Equipment Descriptions ................................................................................................... 5
2.2
GFC 600 Interfaces.......................................................................................................... 7
2.3
Power Requirements ....................................................................................................... 7
2.4
Electrical Bonding ............................................................................................................ 7
3. CONTROL AND OPERATION............................................................................................. 10
3.1
GMC 605........................................................................................................................ 10
3.2
Autopilot Disconnect/Trim Interrupt Switch .................................................................... 10
3.3
Trim Switch .................................................................................................................... 10
3.4
Control Wheel Steering (CWS) Switch .......................................................................... 10
3.5
Go Around (GA) Switch ................................................................................................. 10
3.6
Low Bank Switch............................................................................................................ 10
4. INSTRUCTIONS FOR CONTINUED AIRWORTHINESS .................................................... 11
4.1
Airworthiness Limitations ............................................................................................... 11
4.2
Servicing Information ..................................................................................................... 12
4.3
Maintenance Intervals .................................................................................................... 14
4.4
Visual Inspection ............................................................................................................ 15
4.5
Electrical Bonding Test .................................................................................................. 16
4.6
Sonalert Functional Test ................................................................................................ 17
5. TROUBLESHOOTING ......................................................................................................... 18
5.1
GMC 605 Configuration Mode Test Faults .................................................................... 18
5.2
GMC 605 Normal Mode Failure Annunciations ............................................................. 20
5.3
GMC 605 Troubleshooting ............................................................................................. 22
5.4
GSA 87 Troubleshooting................................................................................................ 22
5.5
GI 285 Troubleshooting ................................................................................................. 22
5.6
GTA 82 Troubleshooting ................................................................................................ 22
5.7
Backshell/Backplate Connectors ................................................................................... 23
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6. EQUIPMENT REMOVAL & INSTALLATION ...................................................................... 24
6.1
GMC 605........................................................................................................................ 24
6.2
GI 285 ............................................................................................................................ 25
6.3
GSA 87 Servos .............................................................................................................. 26
6.4
GTA 82 Trim Adapter ..................................................................................................... 27
6.5
Air Data Module (ADM) .................................................................................................. 27
6.6
Configuration Module Removal & Replacement ............................................................ 29
7. GARMIN GFC 600 LRU REPLACEMENT/CONFIGURATION & TESTING ....................... 31
7.1
GMC 605........................................................................................................................ 31
7.2
GSA 87 Servo ................................................................................................................ 31
7.3
GI 285 AFCS Mode Annunciator ................................................................................... 32
7.4
GTA 82 Trim Adapter ..................................................................................................... 32
7.5
Configuration Module ..................................................................................................... 32
7.6
Air Data Module (ADM) .................................................................................................. 32
8. GFC 600 SOFTWARE LOAD AND CONFIGURATION PROCEDURES ............................ 33
8.1
GMC 605 and GSA 87 Software Loading ...................................................................... 33
8.2
GI 285 Software ............................................................................................................. 33
8.3
GFC 600 System Configuration ..................................................................................... 34
9. GFC 600 RETURN TO SERVICE PROCEDURE ................................................................ 40
9.1
Pitot and Static System Leak Check .............................................................................. 40
9.2
Configuration Mode Tests .............................................................................................. 40
9.3
Pre-Flight Test (PFT) ..................................................................................................... 42
9.4
Normal Mode Tests........................................................................................................ 43
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Revision 6
LIST OF ILLUSTRATIONS
FIGURE
PAGE
Figure 2-1 – GMC 605 .................................................................................................................. 5
Figure 2-2 – GI 285 ....................................................................................................................... 6
Figure 2-3 – Electrical Bonding Preparation – Nut Plate .............................................................. 8
Figure 2-4 – Electrical Bonding Preparation – Bolt/Nut Joint ........................................................ 8
Figure 2-5 – Electrical Bonding Preparation – Terminal Lug ........................................................ 9
Figure 5-1 – GMC 605 Backplate, viewed from rear of rack ....................................................... 23
Figure 5-2 – GMC 605 Connector View from Wire Entry (P6051 and P6052) ............................ 23
Figure 5-3 – GSA 87 Connector View from Wire Entry (1P871, 2P871, 3P871, 4P871) and GTA
82 Connector View (P821)................................................................................................... 23
Figure 5-4 – GI 285 Connector from Unit Side (P2851) .............................................................. 23
Figure 6-1 – GMC 605 Installation and rack/backplate assembly ............................................... 25
Figure 6-2 – GI 285 Installation ................................................................................................... 26
Figure 6-3 – ADM Installation ..................................................................................................... 28
Figure 6-4 – Configuration Module Installation ........................................................................... 29
Figure 8-1 – Configuration Pages Block Diagram ....................................................................... 34
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Revision 6
LIST OF TABLES
TABLE .................................................................................................................................. PAGE
Table 1-1 – Required Documents ................................................................................................. 3
Table 1-2 – Garmin Reference Documents .................................................................................. 3
Table 1-3 – Other Reference Documents ..................................................................................... 4
Table 2-1 – Power Requirements ................................................................................................. 7
Table 2-2 – Electrical Bonding ...................................................................................................... 8
Table 4-1 – Maintenance Intervals .............................................................................................. 14
Table 4-2 – Visual Inspection Procedure .................................................................................... 15
Table 4-3 – Lightning Strike Inspection Procedure ..................................................................... 16
Table 5-1 – Configuration Mode Test Faults ............................................................................... 18
Table 5-2 – Normal Mode Failures ............................................................................................. 20
Table 6-1 – Configuration Module Kit ......................................................................................... 29
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Revision 6
1. Introduction
1.1 Content, Scope, Purpose
This document provides maintenance instructions and Instructions for Continued Airworthiness
(ICA) for the GFC 600 Automatic Flight Control System (AFCS) as installed under STC
SA01844WI. This document satisfies the requirements for continued airworthiness as defined
by 14 CFR Part 23.1529 and 14 CFR Part 23 Appendix G.
1.2 Applicability
This document applies to all Part 23 aircraft equipped with the GFC 600 installed under AML
STC SA01844WI.
Modification of an aircraft by this Supplemental Type Certificate (STC) obligates the aircraft
operator to include the maintenance information provided by this document in the operator’s
Aircraft Maintenance Manual and the operator’s Aircraft Scheduled Maintenance Program.
1.3 Organization
The following outline briefly describes the organization of this manual:
Section 2: System Description
Provides a complete description of the type design change associated with installing the GFC
600 AFCS. Also provides an interface summary, power requirements, and instructions on
electrical bonding.
Section 3: Control and Operation
Provides brief instructions on controls and operation.
Section 4: Instructions for Continued Airworthiness
Provides maintenance instructions for continued airworthiness of the GFC 600 AFCS.
Section 5: Troubleshooting
Provides troubleshooting information to aid in diagnosing and resolving potential problems with
the GFC 600 AFCS.
Section 6: Equipment Removal & Replacement
Gives instructions for the removal and replacement of GFC 600 AFCS equipment.
Section 7: Garmin GFC 600 LRU Replacement/Configuration & Testing
Gives instructions for loading software, configuring, and testing of GFC 600 AFCS equipment.
Section 8: Software Load and Configuration Procedures
Gives instructions for loading software and configuring the GFC 600 AFCS.
Section 9: GFC 600 Return to Service Procedure
Specifies return-to-service procedures to be performed upon completion of maintenance of the
GFC 600 AFCS.
GFC 600 AFCS Part 23 AML STC Maintenance Manual
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Revision 6
1.4 Definitions/Abbreviations
AFCS:
AFM:
AFMS:
AHRS:
AML:
CDI:
CFR:
CWS:
DDM:
DTK:
ESD:
ESL:
ESP:
FAA:
HSDB:
HSI:
ICA:
LRU:
OBS:
PFD:
PFT:
POH:
STC:
TSO:
USB:
WAAS:
Automatic Flight Control System
Airplane Flight Manual
Airplane Flight Manual Supplement
Attitude and Heading Reference System
Approved Model List
Course Deviation Indicator
Code of Federal Regulations
Control Wheel Steering
Difference in Depth of Modulation
Desired Track
Electro-Static Discharge
Electronic Speed Limiting
Electronic Stability Protection
Federal Aviation Administration
High Speed Data Bus
Horizontal Situation Indicator
Instructions for Continued Airworthiness
Line Replaceable Unit
Omni-Bearing Selector
Primary Flight Display
Pre-Flight Test
Pilot’s Operating Handbook
Supplemental Type Certificate
Technical Standard Order
Universal Serial Bus
Wide Area Augmentation System
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Revision 6
1.5 Reference Publications
All of the documents listed in Table 1-1 and Table 1-2 are available for download through the
Dealer Resource Center section of the Garmin web site. Refer to Section 1.6 for details.
The documents listed in Table 1-1 are required by this maintenance manual to perform
maintenance on the GFC 600 AFCS. It is the responsibility of the owner/operator to ensure that
the latest versions of these documents are used during operation, servicing or maintenance of
the airplane. Note: There is a model-specific installation manual addendum for each model
covered. Each has a different dash number. Refer to the Master Drawing List 005-01009-01 for
applicability.
Table 1-1 – Required Documents
Document Number
Title
005-01009-01
Master Drawing List GFC 600 Automatic Flight Control System Part 23 AML STC
005-01009-05
Equipment List GFC 600 Automatic Flight Control System Installation Part 23 AML STC
190-01937-00
GFC 600 AFCS Part 23 AML STC Installation Manual
190-01937-XX
GFC 600 AFCS Part 23 AML STC Model-Specific Installation Manual Addendum
190-01488-00
GFC 600 Pilot’s Guide
The documents listed in Table 1-2 are recommended to be available during the performance of
maintenance activities.
Table 1-2 – Garmin Reference Documents
Document Number
Title
190-01488-01
GMC 605 Installation Manual
190-01903-00
GSA 87 Installation Manual
190-00303-98
GI 285 Installation Manual
190-00067-22
GPS 155XL/GNC 300XL Installation Manual
190-00140-02
400 Series Installation Manual
190-00149-01
GMA 340 Audio Panel Installation Manual
190-00181-02
500 Series Installation Manual
190-00303-15
GDC 74(X) Air Data Computer Installation Manual
190-00303-74
GTA 82 Installation Manual
190-00325-01
GMA 347 Audio Panel Installation Manual
190-00356-08
GNS 400W Series Installation Manual
190-00357-08
GNS 500W Series Installation Manual
190-00601-04
GDU 620 Installation Manual
190-00858-11
GMA 35/35c Installation Manual
190-01004-02
GTN 625/635/650 TSO Installation Manual
190-01007-02
GTN 725/750 TSO Installation Manual
190-01112-10
G5 Electronic Flight Instrument Part 23 AML STC Installation Manual
190-01134-11
GMA 350/350c/350H350Hc Installation Manual
190-01499-02
GTX 3X5 Transponder TSO Installation Manual
190-01639-00
GSU 75 ADAHRS Installation Manual
GFC 600 AFCS Part 23 AML STC Maintenance Manual
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Revision 6
190-01717-00
G500/G600 TXi TSO Installation Manual
190-01855-00
GDC 72 Air Data Computer Installation Manual
560-0979-00
Apollo Model SL15 Audio Selector Panel Installation Manual
560-0982-01
GNS 480 (CNX80) Color GPS/NAV/COM Installation Manual
Document Number
Title
AC 43.13-1B
FAA Advisory Circular, Acceptable Methods, Techniques, and Practices
– Aircraft Inspection and Repair
AC 43.13-2B
FAA Advisory Circular, Acceptable Methods, Techniques, and Practices
– Aircraft Alterations
SAE ARP1870
Aerospace Systems Electrical Bonding and Grounding for Electromagnetic Compatibility
and Safety
SAE AS4461
Assembly and Soldering Criteria for High Quality/High Reliability Soldered Wire and
Cable Termination in Aerospace Vehicles
SAE AS50881
Wiring, Aerospace Vehicle
ASTM F 2490-05
Standard Guide for Aircraft Electrical Load and Power Source Capacity Analysis
Table 1-3 – Other Reference Documents
1.6 Revision and Distribution
This document is required for maintaining the continued airworthiness of the GFC 600 AFCS.
When this document is revised, every page will be revised to indicate current revision level.
Garmin Dealers may obtain the latest revision of this document on the Garmin Dealer Resource
Center website.
Owner/operators may obtain the latest revision of this document from the https://fly.garmin.com/
Support page, or by contacting a Garmin dealer, contacting Garmin Product Support at 913397-8200, toll free 866-739-5687, or using around the world contact information on
https://fly.garmin.com/.
A Garmin Service Bulletin describing the revision to this document will be sent to Garmin
dealers if the revision is determined to be significant.
1.7 Garmin Technical Support
For technical support contact, Garmin Aviation Product Support at 913-397-8200 (toll free 866739-5687) or by using the around the world contact information on www.flygarmin.com.
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Revision 6
2. System Description
2.1 Equipment Descriptions
2.1.1 GMC 605 AFCS Mode Controller
The GMC 605 Automatic Flight Control System (AFCS) mode controller is shown in Figure 2 1.
The front panel of the GMC 605 includes a monochrome display that provides AFCS status
indications, autopilot and flight director mode indications, and other system indications. The
GMC 605 performs flight director computations. It contains an internal attitude board which is
used to provide the attitude reference input to the AFCS computations. The internal attitude
board requires air data aiding to provide a valid attitude solution and will also use GPS/WAAS
aiding to provide additional accuracy of the attitude solution.
The GMC 605 provides the AFCS commands directly to the GSA 87 servos. Refer to the GFC
600 Pilot’s Guide, 190-01488-00 for operational characteristics of the system.
Figure 2-1 – GMC 605
2.1.2 GSA 87 Servo
The GSA 87 servo uses a dual processor providing for a fail passive design. It uses a brushless
DC motor that requires software commutation. The GSA 87 runs application software
appropriate to the axis it is installed in, as programmed by the four installation straps on the
servo connector. The possible strap selections include pitch, roll, yaw damper, and pitch trim.
The GSA 87 uses a position-based motor-control loop. Output torque is computed based on
sensed motor current. The GSA 87 uses electronic speed limiting (ESL) to control the
maximum speed of the servo to prevent rapid changes in flight control surface movement.
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Revision 6
2.1.3 GI 285 Mode Annunciator Panel
The GI 285 mode annunciator panel (if installed) interfaces directly with the GMC 605 to provide
AFCS mode annunciations to the pilot (see Figure 2 2).
Figure 2-2 – GI 285
2.1.4 Audio Output
The GMC 605 has an analog audio output to an audio panel, plus an active low output to drive
an external aural alert device (e.g. sonalert). The analog audio can be interfaced to any audio
panel that has an unswitched and unmuted analog audio input. If the analog audio is interfaced
to an audio panel other than a GMA 35 or GMA 350, which has a fail-safe audio path, the
installation must also include a sonalert.
2.1.5 Garmin Air Data Module (ADM)
The ADM (if installed) provides pitot and static pressure input to the GMC 605 via connection to
the existing aircraft pitot and static systems. The ADM contains an internal configuration
module, and when installed replaces the GMC 605 configuration module. The ADM uses the
same I2C interface to the GMC 605 that the configuration module would use with the exception
that the ADM wiring harness includes an additional wire for unit power.
In some installations, the ADM is utilized as a cabin pressure sensor. In this case, an approved
air data source is required, and the ADM is not connected to the existing pitot and static
systems.
2.1.6
GTA 82 Trim Adapter
The Garmin GTA 82 Trim Adapter is a remote mounted device that is used to allow the GFC
600 to drive a trim actuator provided by the airframe manufacturer. In these cases, the GTA 82
provides the required interface.
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Revision 6
2.2 GFC 600 Interfaces
The GFC 600 AFCS is capable of interfacing with many different external units. Refer to the
installation-specific information in the aircraft records to determine which interfaces are
applicable.
2.3 Power Requirements
Table 2-1 below summarizes the power requirements for the GFC 600 LRUs.
LRU
GMC 605
GSA 87
GI 285
GTA 82
Table 2-1 – Power Requirements
Characteristics
Specifications
Average Current Draw @ 14 VDC
0.53 A
Max Current Draw @ 14 VDC
1.15 A
Average Current Draw @ 28 VDC
0.27 A
Max Current Draw @ 28 VDC
0.70 A
Average Current Draw @ 14 VDC
2.6 A
Max Current Draw @ 14 VDC
3.0 A
Average Current Draw @ 28 VDC
1.3 A
Max Current Draw @ 28 VDC
1.5 A
Average Current Draw @ 14 VDC
65 mA
Max Current Draw @ 14 VDC
154 mA
Average Current Draw @ 28 VDC
36 mA
Max Current Draw @ 28 VDC
84 mA
No-Load Current Draw @ 28 VDC
60 mA
Continuous Current Draw @ 28 VDC
3.0 A
Max Current Draw @ 28 VDC
6.0 A
2.4 Electrical Bonding
For the purposes of this STC, aircraft ground reference definitions vary according to airframe
type as defined in Table 2-2. Refer to the periodic test and reconditioned resistance values
corresponding to these ground reference definitions when performing the equipment bonding
tests in Section 4.5.
The periodic test value is the value allowed during the bonding checks specified in Section 4.5.
The reconditioned value is the value allowed on initial installation or if the bond must be
reworked if the periodic test value is exceeded.
Refer to SAE ARP 1870 Section 5 when surface preparation is required to achieve electrical
bond.
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Revision 6
Aircraft Type
Metallic Airframe
Table 2-2 – Electrical Bonding
Maximum Resistance Between GFC
600 Equipment Chassis and Ground
Ground Reference
Reference (mΩ)
Nearby metal structure for
servos
Instrument panel for GMC
605 and GI 285
Periodic Test
Reconditioned
10.0
2.5
2.4.1 Consideration for Untreated or Bare Dissimilar Metals
The correct material finish is important when mating untreated or bare dissimilar metals.
Materials should be galvanically compatible. When corrosion protection is removed to make an
electrical bond any exposed area after the bond is completed should be protected again.
Additional guidance can be found in AC 43.13-1B and SAE ARP 1870. Typical electrical
bonding preparation examples are shown in Figure 2-3, Figure 2-4, and Figure 2-5.
Figure 2-3 – Electrical Bonding Preparation – Nut Plate
Figure 2-4 – Electrical Bonding Preparation – Bolt/Nut Joint
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Revision 6
Figure 2-5 – Electrical Bonding Preparation – Terminal Lug
2.4.2 Preparation of Aluminum Surfaces
The following general procedure is recommended to prepare an aluminum surface for proper
electrical bonding. Refer to Figure 2-3, Figure 2-4, and Figure 2-5 for additional information.
1. Clean grounding location with solvent.
2. Remove non-conductive films or coatings from the grounding location.
3. Apply a chemical conversion coat such as Alodine 1200 to the bare metal.
4. Once the chemical conversion coat is dry, clean the area.
5. Install bonding equipment at grounding location.
6. After bond is complete, if any films or coatings were removed from the surface, reapply a
suitable film or coating to the surrounding area within 24 hours.
In cases where the parts come in with certain areas spot-faced, or if the there is no finish on the
part (bare metal), apply conformal coating over the bond joint and hardware per MIL-I-46058 or
clear lacquer per TT-L-20A in order to facilitate future inspection. Refer to the model specific
Aircraft Maintenance Manual or Standard Practices Manual for surface protection requirements
applicable to affected areas. When corrosion protection is removed to make an electrical bond,
any exposed area after the bond is completed should be protected again. Additional guidance
can be found in AC 43.13-1B and SAE ARP 1870.
For a more detailed procedure, refer to SAE ARP 1870 Sections 5.1 and 5.5.
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3. Control and Operation
3.1 GMC 605
The GMC 605 provides GFC 600 AFCS mode selections and annunciations. Refer to the GFC
600 Pilot’s Guide, 190-01488-00, for operational characteristics of the system.
3.2 Autopilot Disconnect/Trim Interrupt Switch
An AP DISC/TRIM INT switch is provided on the pilot’s flight controls to allow for manual
disconnect of the autopilot system and to interrupt the electric pitch trim. Pressing and holding
the AP DISC/TRIM INT switch for more than 5 seconds will turn off the Electronic Stability and
Protection (ESP) feature.
3.3 Trim Switch
If the GFC 600 AFCS includes a pitch trim servo, a TRIM switch is provided on the pilot’s flight
controls to allow for manual electric control of the pitch trim system. Both halves of the TRIM
switch must be pushed simultaneously for the pitch trim servo to engage and run in the
requested direction. If the autopilot is engaged and the TRIM switch is pressed, the autopilot
will disengage.
3.4 Control Wheel Steering (CWS) Switch
A CWS switch is provided on the pilot’s flight controls. Pressing the CWS switch will disengage
the autopilot servos from the flight control system for as long as the switch is pressed. The
autopilot servos will re-engage at the current flight attitude when the switch is released.
3.5 Go Around (GA) Switch
A GO AROUND switch is provided for engagement of the go around mode. When go around
mode is engaged, the autopilot engages in wings level roll attitude and nose up pitch attitude.
The pitch attitude is dependent on the aircraft model. Refer to the appropriate GFC 600 AFCS
Airplane Flight Manual Supplement for the go around pitch attitude. Refer to the appropriate
model-specific installation manual addendum (190-01937-XX) for switch installation location.
3.6 Low Bank Switch
A LOW BANK switch is provided in some airframes for engagement of the low bank mode.
When low bank mode is engaged, the autopilot utilizes a lower bank angle limit. Refer to the
GFC 600 Equipment List to determine if LOW BANK is supported in the specific model. Refer
to the appropriate model-specific installation manual addendum (190-01937-XX) for switch
installation location.
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Revision 6
4.2 Servicing Information
Servicing of the GFC 600 AFCS equipment is ‘on condition’. In the event of system failure,
troubleshoot the GFC 600 AFCS in accordance with Section 5.
4.2.1 On Condition Servicing
‘On Condition’ replacement and/or servicing should occur when an item exhibits conditions,
symptoms, and/or abnormalities defined in Section 5 of this manual. Replacement and/or
servicing should be made only after the technician troubleshoots the system to the extent
determined necessary by using the guidance in this manual along with common avionics
maintenance practices.
The remainder of this document is organized in the following fashion:
•
Section 4.3 lists maintenance requirements related to the GFC 600 AFCS.
•
Section 6 gives instructions regarding the removal and replacement of GFC 600
equipment and parts.
•
Section 7 gives configuration and testing instructions to be accomplished if GFC 600
equipment or parts are removed or replaced.
•
Section 9 specifies system return-to-service procedures.
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Revision 6
4.2.2 Required Tools
The following tools are needed to perform maintenance tasks on GFC 600 AFCS equipment:
•
Calibrated Milliohm meter with Kelvin probes, OR
o
Calibrated Ammeter capable of measuring 1.5 Amps of current with a minimum
resolution of 0.1A.
o
Calibrated Voltmeter capable of measuring millivolts with a minimum resolution
of 0.1mV
o
Variable DC Power Supply capable of providing 1 amp current
•
3/32” Hex tool
•
Calibrated VHF NAV/COM/ILS ramp tester
•
Calibrated pitot/static ramp tester
•
Outdoor line-of-site to GPS satellite signals or GPS indoor repeater
•
Headset/microphone
•
Ground Power Unit
•
Calibrated Flight Control Cable Tension Meter
•
Calibrated torque wrench capable of measuring 0 – 70 in/lbs.
•
Standard sockets & wrenches
4.2.3 Special Tools
There are no special tools required to perform maintenance on the GFC 600 AFCS.
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Revision 6
4.3 Maintenance Intervals
Table 4-1 shows systems and items, installed by this STC, which must undergo tests or checks
at specific intervals. If the interval is shown to be in flight time as well as calendar months, the
first interval reached should be used as the limit.
Those inspections that are based on flight time or calendar elapsed time or cycles shall have
specific intervals stated in Table 4-1.
Table 4-1 – Maintenance Intervals
Item
Description/Procedure
Manual
Section No.
Interval
Equipment electrical
Bonding Test
Verify bonding of GMC 605 rack, GI
285 rack (if installed), GSA 87
mounting brackets, GTA 82, and any
associated bonding components
4.5
Following removal
and replacement of
the racks or brackets
AND
Every 2000 flight
hours or ten years,
whichever is first
Equipment Bonding Visual
Inspection – suspected
lightning strike
Inspection of bonding Components
Table 4-3
At any suspected or
actual lightning
strike
GFC 600 Equipment
Visual Inspection
Visual inspection of GFC 600
components
4.4
At every annual
inspection
Sonalert Disconnect Tone
Check (if installed)
Functional test of Sonalert
4.6
At every annual
inspection
GSA 87 Servos
Removal and Replacement
6.3
On Condition
GMC 605 Autopilot
Computer
Removal and Replacement
6.1
On Condition
Air Data Module
Removal and Replacement
6.5
On Condition
GI 285 Autopilot
Annunciator
Removal and Replacement
6.2
On Condition
GTA 82 Trim Adapter
Removal and Replacement
6.4
On Condition
Table 4-2
With aircraft
manufacturer’s
required primary
control cable checks
Servos, Servo Control
Cables/Chains and
associated hardware
Visual Inspection
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4.4 Visual Inspection
Perform a visual inspection in accordance with requirements in Table 4-2. Check for corrosion,
damage, or other defects of the GMC 605, GI 285 (if installed), and the GSA 87s. Replace any
damaged parts as required. Inspection may require the temporary removal of a unit or units to
gain access to connectors. Follow guidance in Section 6 for equipment removal and
replacement. Refer to the aircraft manufacturer service or maintenance manual for instructions
on access panel locations.
Table 4-2 – Visual Inspection Procedure
Item
Description/Procedure
a)
Conduct a visual inspection of the GMC 605, GI 285 (if installed), and GSA 87
equipment installations in accordance with 14 CFR Part 43, Appendix D. If the
equipment does not pass the visual inspection, complete the following procedure:
i.
Correct improper installations and ensure that all install racks, brackets, and
fasteners are secure. Correct improper wire routing and ensure that the wire
harness is securely mounted. Replace install racks, brackets, wiring and
associated electrical bonding or shielding components with obvious defects
ii.
Complete the equipment electrical bonding test as described in section 4.5 for any
components that are replaced.
GFC 600 Equipment
Visual Inspections
b)
Servos, Servo
Control Cables, and
associated hardware
Initials
Inspect all exposed wire harness for chafing, damage, proper routing of wire bundles
and security of attachment in accordance with AC 43.13-1B, Chapter 11, Section 8,
Paragraph 11-96.
a)
Using a flashlight, inspect the GSA 87 servos, connectors, support structure, and
control cables to ensure that no corrosion, chafing, cracks, or other defects exist.
b)
Have an assistant manually move the control surfaces from stop to stop and visually
observe the servo and control cabling/chain. Ensure there is no binding in the control
cabling or chain, that the capstan/sprocket rotates freely, and that there is no rough
turning or noise from the servo bearings.
c)
Check the servo control cables in accordance with AC 43.13-1B, Chapter 7, Section
8, Paragraph 7-149 to ensure no fraying, corrosion, or other damage exists. If the
condition of any cable is questionable, replace it with a new one.
d)
Check the tension on the servo control cables. Refer to the appropriate Install
Manual Addendum for the aircraft type for cable tension specifications:
e)
Ensure that each cable is correctly attached to the clamps.
f)
Visually inspect the hydrophobic vents on the GSA 87 servos to ensure that there is
no debris present.
g)
Visually inspect the condition of lock nuts, cable guard support plate, cable guard
posts, self-locking castle nuts, cotter pin, split lock washer, flat washer and the output
shaft to ensure no corrosion, cracks, or other defects exist.
h)
For continuous travel servos only (p/n 011-03780-01), visually inspect the condition
of the idler pulley, shaft, washer, and E-ring, to ensure no corrosion, chafing, cracks,
or other defects exist.
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Table 4-3 – Lightning Strike Inspection Procedure
Item
Description/Procedure
Initials
GMC 605, GI 285 (if
installed), GSA 87,
GTA 82
In the event of a suspected or actual lightning strike to the aircraft, the bonding
components for the GFC 600 AFCS (bonding straps, mounting hardware etc.) must be
inspected. If any damage is found, damaged components must be replaced in accordance
with specifications and procedures shown in Section 6. If any bonding components are
replaced, measure the resistance between the replaced component and aircraft ground.
Verify the resistance is less than or equal to 2.5mΩ.
4.5 Electrical Bonding Test
The following bonding tests are provided for aircraft that have a GFC 600 AFCS installed as a
requirement beyond any that may be given in the aircraft maintenance manual.
4.5.1 Requirements
All GFC 600 equipment must be installed. For the GMC 605 and GI 285, the tests are
performed with the connectors connected. For the GSA 87, tests are conducted with the
connector disconnected. Gain access for the procedure listed below in Section 4.5.3 as
required and in accordance with the aircraft maintenance manual. It is recommended that
these tests are conducted after visual inspection of the zone to minimize access requirements.
4.5.2 Test Equipment
A milliohm meter and Kelvin probes are recommended for this test. However, an alternate
method may be used to provide equivalent results by using the following procedure and a
standard voltmeter, power supply with adjustable current limit, and ammeter. The test set up for
this alternate method is described below.
All test equipment used for the bond checks must be calibrated.
1. Connect the positive lead of the power supply to airframe ground. Connect/touch the
positive lead of the voltmeter to the same point.
NOTE
Ensure that the voltmeter and power supply probes do not touch, so as not to
induce contact resistance.
2. Touch negative lead of power supply to each of the test points listed while performing
Step 3. At each required point, configure the power supply to produce 1 amp before
measuring voltage. (Use an ammeter to ensure current is within minimum of 1 amp
±100 milliamp at each point). Do not allow the reference current to exceed 1.5 amps for
safety.
3. With the current set to 1A, the voltage reading will be the value of the bonding
resistance. Set the voltmeter to measure millivolts and null the reading. Measure the
voltage from airframe ground (step 1) to each required test points and record the
voltage. (Perform Step 2 at each required point and ensure that minimum of 1 amp
±100 milliamp is present when measuring the voltage.)
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TIP: When a 1A current is used all the millivolt readings are the same as mΩ, and
required no further calculation of bond resistance. If 1 amp reference current cannot
be maintained and is higher divide the measured voltage by current to get the
resistance value.
4.5.3 Electrical Bonding Procedure
Using one of the two measurement methods in Section 4.5.2 record the bonding measurement
for the following equipment. Some equipment in the list is optional and may not be installed.
Ensure that the measurements do not exceed the values shown in Table 2-2. If the values
exceed those listed, perform the reconditioning procedure in Section 2.4.
•
•
•
•
•
•
•
GMC 605 case: __________ mΩ
GI 285 case: __________ mΩ
GSA 87 (Roll) chassis: __________ mΩ
GSA 87 (Pitch) chassis: __________ mΩ
GSA 87 (Pitch Trim) chassis: __________ mΩ
GSA 87 (Yaw Damper) chassis: __________ mΩ
GTA 82 (Trim Adapter) chassis: __________ mΩ
4.6 Sonalert Functional Test
If a Sonalert is installed, perform the Sonalert Functional Test at the intervals specified in Table
4-1.
1. Apply external electrical power to the aircraft and avionics systems.
2. Ensure that the GFC 600 AFCS passes PFT.
3. Engage the autopilot by pressing the AP button on the GMC 605.
4. Disengage the autopilot by pressing the AP DISC/TRIM INT switch on the pilot’s flight
controls.
5. Verify that the normal autopilot disconnect tone plays through the sonalert. NOTE: The
normal autopilot disconnect sonalert tone is a continuous 2000 Hz tone that plays for
approximately 10 seconds.
6. Engage the autopilot by pressing the AP button on the GMC 605.
7. Pull the AUTOPILOT circuit breaker.
8. Verify that the abnormal autopilot disconnect tone plays through the sonalert until the
GMC 605 powers down completely. NOTE: The abnormal autopilot disconnect sonalert
tone is a continuous 2000 Hz tone.
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5. Troubleshooting
This section provides information to assist with troubleshooting if problems occur. See the GFC
600 AFCS Configuration Log retained in the aircraft permanent records for a list of the
interfaced equipment and system configuration data. When troubleshooting the GFC 600
AFCS, refer to the interconnect diagrams retained with the aircraft permanent records.
Before troubleshooting the GFC 600 AFCS, ensure that system configuration settings match
those recorded in the completed GFC 600 AFCS Configuration Log that is retained in the
aircraft permanent records.
5.1 GMC 605 Configuration Mode Test Faults
During initial installation, or during certain periodic maintenance tasks, there may be tests done
in configuration mode. During these tasks, there could be fault messages displayed. Refer to
Table 5-1 below for troubleshooting steps.
Table 5-1 – Configuration Mode Test Faults
Troubleshooting
Approach
Procedure
Annunciated Fault
Possible Cause
Engine Run-Up test
TEST FAILED:
TIMEOUT
Data communications
failure
Check system wiring.
TEST FAILED:
INVALID READY
STATE
Mounting orientation in
configuration is incorrect or
the sub-procedure is not
known
Ensure that configuration
settings are the same as
those retained with the
aircraft records.
TEST FAILED:
AIRCRAFT IN
MOTION
Aircraft is moving, or
incorrect sensor calibration,
or sensor failure, or
incorrect air data
information.
Make sure that GMC
605 rack is mounted as
shown in the Installation
manual
TEST FAILED: GRS
NOT CALIBRATED
Sensor calibration is not
done. Inertial and
temperature sensor
calibration data may be
corrupted.
Contact Garmin Aviation
Product Support using
the contact information
in Section 1.7
TEST FAILED:
UNKNOWN
FAILURE
AHRS provided invalid
failure code
Contact Garmin Aviation
Product Support using
the contact information
in Section 1.7
OR
Pitch/Roll Offset
Calibration test
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Verify valid GPS or air
data is available to the
GMC.
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Engine Run-Up test
Pitch/Roll Offset
Calibration test
TEST FAILED:
CHECK RESULTS
Test completed with no
errors, but not all sub-tests
passed. Check results
page.
Cycle power to the GFC
600 AFCS and repeat
the test. If test fails
again, contact Garmin
Aviation Product Support
using the contact
information in Section
1.7.
TEST FAILED:
INERTIAL
MEASUREMENT
PROCESSING
ERROR
Test completed with inertial
measurement processing
error.
Cycle power to the GFC
600 AFCS and repeat
the test. If test fails
again, contact Garmin
Aviation Product Support
using the contact
information in Section
1.7.
TEST FAILED:
INVALID TILT
AHRS tilt sensor or
accelerometer failure.
Sensor is bad or calibration
data corrupted.
Replace the GMC 605.
TEST FAILED:
INVALID PITCH
OFFSET
Zero pitch/roll cal with nonzero pitch value. Pitch
offset value out of predefined range.
Check aircraft level and
repeat test.
TEST FAILED:
INVALID ROLL
OFFSET
Zero pitch/roll cal with nonzero roll value
Check aircraft level and
repeat test.
TEST FAILED:
RESULT NOT
SAVED
Non-volatile storage failed.
Replace the
configuration module or
air data module.
TEST FAILED: CRC
FAILED
Data communications
failure or incorrect data
content
Check configuration
module or Air Data
Module wiring.
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5.2 GMC 605 Normal Mode Failure Annunciations
During normal operation of the GFC 600 AFCS, the GMC 605 may annunciate a failure.
Consult Table 5-2 below for assistance in troubleshooting.
Table 5-2 – Normal Mode Failures
Annunciated
Fault
Possible Cause
Troubleshooting Approach
AP FAIL
GI 285 failure
Check that the GI 285 electrical connector is
securely attached.
Verify wiring between GMC 605 and GI 285.
Servo failure
Check each servo and verify that the electrical
connectors are securely attached.
Verify wiring between GMC 605 and all installed
servos.
Invalid attitude (including AHRS
monitor and attitudes outside
engage limits)
Recycle GFC 600 power.
Verify wiring between GMC 605 and Air Data
Computer (or ADM).
Verify wiring between GMC 605 and GPS 232
connections.
AP Disconnect in invalid state
Ensure that the AP DISC / TRIM INT switch is not
stuck or shorted.
Verify wiring between GMC 605 and AP
DISC/TRIM INT Switch.
AIRDAT FAIL
Air Data Inputs have failed
If the system is interfaced to an air data computer,
verify that the air data computer is functioning
properly.
If the system includes an ADM, verify that the
ADM wiring harness is securely attached to the
mating connector on the ADM and that there are
no chafed or broken wires.
Ensure that the pitot and static systems are free of
debris and obstructions.
P TRIM FAIL
Pitch Trim Servo failure
Check the pitch trim servo and verify that the
electrical connector is securely attached.
Verify wiring between Pitch Trim Servo and GMC
600.
Verify that the aircraft has a pitch trim servo
installed. If it does not, verify the configuration of
the GMC 605.
Stuck TRIM switch
Check the trim switch and ensure that both halves
operate smoothly in both directions.
Verify wiring between the trim switch and the
GMC 605.
ESP FAIL
PFT not passed
Recycle GFC 600 power.
Invalid Attitude (including AHRS
monitor and attitudes outside
engage limits)
Verify wiring between GMC 605 and Air Data
Computer (or ADM).
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Verify wiring between GMC 605 and GPS 232
connections.
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GI 285 failure
Check that the GI 285 electrical connector is
securely attached.
Verify wiring between the GI 285 and the GMC
605.
Servo failure (Pitch, Roll, or Pitch
Tim)
Check each servo and verify that the electrical
connectors are securely attached.
Verify wiring between the GMC 605 and the
servos.
AP Disconnect in invalid state
Ensure that the AP DISC / TRIM INT switch is not
stuck or shorted.
Verify wiring between AP DISC/TRIM IT switch
and the GMC 605.
YD FAIL
Yaw Damper Servo failure
Check the yaw damper servo and verify that the
electrical connector is securely attached.
Verify wiring between the Yaw Damper Servo and
the GMC 605.
AP Disconnect invalid state
Ensure that the AP DISC / TRIM INT switch is not
stuck or shorted.
Verify wiring between AP DISC/TRIM IT switch
and the GMC 605
Invalid Attitude (including AHRS
monitor and attitudes outside of
engagement limits)
Recycle GFC 600 power.
Verify wiring between GMC 605 and Air Data
Computer (or ADM).
Verify wiring between GMC 605 and GPS 232
connections.
PFT FAIL
Servo failure
Check each servo and verify that the electrical
connectors are securely attached.
Verify wiring between GMC 605 and all installed
servos.
Interface failure
Check all interface wiring and verify there are no
open wires or shorts to ground.
GI 285 failure
Check that the GI 285 electrical connector is
securely attached.
Verify wiring between the GI 285 and the GMC
605.
AP Disconnect invalid state
Ensure that the AP DISC / TRIM INT switch is not
stuck or shorted.
Verify wiring between AP DISC/TRIM IT switch
and the GMC 605
Invalid attitude
Recycle GFC 600 power.
Verify wiring between GMC 605 and Air Data
Computer (or ADM).
Verify wiring between GMC 605 and GPS 232
connections.
MANIFEST
One or more units is not reporting
the expected software version to the
GMC 605.
Recycle GFC 600 power.
Verify wiring between GMC 605 and GSA 87’s
and GI 285 (if installed).
Reload software (refer to Section 8.1)
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5.3 GMC 605 Troubleshooting
Symptom
Recommended Action
Display blank
•
Check power/ground wiring for GMC 605 unit.
•
Verify that PFT has passed (cycle AUTOPILOT breaker to cause PFT to
restart.
•
Verify wiring to external sensors.
•
Verify wiring to servos.
AP will not engage
Failure message displayed on
screen
Refer to Section 5.2 for specific troubleshooting.
5.4 GSA 87 Troubleshooting
Symptom
PFT will not pass
Servo will not engage (no control
resistance felt)
Recommended Action
•
Verify wiring between GMC 605 and GSA 87.
•
Verify power/ground wiring to GSA 87.
•
Verify wiring of AP DISC/TRIM INT wiring from circuit breaker through AP
DISC/TRIM INT switch to the servo
Verify cable tensions.
•
5.5 GI 285 Troubleshooting
Symptom
No annunciations visible
Recommended Action
•
Recycle AUTOPILOT circuit breaker to cause PFT to start. All
annunciations will flash briefly during PFT.
•
Verify power/ground wiring to GI 285
•
Verify wiring between GI 285 and GMC 605.
5.6 GTA 82 Troubleshooting
Symptom
PFT will not pass
Recommended Action
•
Verify wiring between GMC 605 and GTA 82.
•
Verify power/ground wiring to GTA 82.
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5.7 Backshell/Backplate Connectors
The following figures depict the unit connectors, with views as described.
Figure 5-1 – GMC 605 Backplate, viewed from rear of rack
Figure 5-2 – GMC 605 Connector View from Wire Entry (P6051 and P6052)
Figure 5-3 – GSA 87 Connector View from Wire Entry (1P871, 2P871, 3P871, 4P871)
and GTA 82 Connector View (P821)
Figure 5-4 – GI 285 Connector from Unit Side (P2851)
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6. Equipment Removal & Installation
This section describes how to remove and replace equipment associated with this STC. After
removal and replacement, the system must be configured and tested as described in Section 7.
Refer to the model-specific Installation Manual Addendums for unit locations and details. Refer
to the Master Drawing List, 005-01009-01 for the applicable addendum part number.
CAUTION:
When removing and/or replacing any GFC 600 component, always ensure
that aircraft power is off. Unplug any auxiliary power supplies.
NOTE:
MS21044-XX self-locking nuts are for one time use only and must be replaced if removed.
6.1 GMC 605
Removal:
1. De-energize the GFC 600 system by pulling the AUTOPILOT circuit breaker.
2. Insert a 3/32” hex drive tool into the access hole at the bottom of the face of the unit.
3. Turn the hex drive tool counterclockwise until the tool stops.
4. Pull the unit from the rack.
Reinstallation:
NOTE:
Ensure the position of the GMC 605 retention mechanism is correct by inserting a 3/32” hex drive
tool into the access hole at the bottom of the face of the unit and turning the tool counterclockwise
until it fully stops.
1. Visually inspect the connector and pins for signs of damage. Repair any damage.
2. Slide the unit into the rack until it stops.
3. Insert a 3/32” hex drive tool into the access hole at the bottom of the face of the unit.
4. Gently push on the GMC 605 bezel while turning the tool clockwise until the unit is
securely seated in the rack. Do not exceed 8 in-lbs. of torque.
5. Perform a software load (if required) and functional check of the GMC 605 as required
per Section 7.1.
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Figure 6-1 – GMC 605 Installation and rack/backplate assembly
6.2 GI 285
Removal:
1. De-energize the GFC 600 system by pulling the AUTOPILOT Circuit breaker.
2. Insert a 3/32” hex drive tool into the access hole at the bottom of the face of the unit.
3. Turn the hex drive tool counterclockwise until the hex drive tool stops.
4. Pull the unit from the rack.
5. Detach P2851 from the mating connector on the GI 285.
Reinstallation:
NOTE:
Ensure the position of the GI 285 retention mechanism is correct by inserting a 3/32” hex drive
tool into the access hole at the bottom of the face of the unit and turning the tool counterclockwise
until it fully stops.
1. Visually inspect the connectors to ensure there are no bent or damaged pins. Repair
any damage.
2. Reattach P2851 to the mating connector on the GI 285.
3. Slide unit into the rack until it stops.
4. Insert a 3/32” hex drive tool into the access hole at the bottom of the face of the unit.
5. Push on the left side of the GI 285 bezel while turning the hex drive tool clockwise until
the unit is securely seated in the rack. Do not exceed 8 in-lbs of torque.
6. Perform a functional check of the GI 285 per Section 7.3.
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Figure 6-2 – GI 285 Installation
6.3 GSA 87 Servos
Removal:
1. Ensure that there is no electrical power to GSA 87 servos by pulling the AUTOPILOT
circuit breaker and AUTOPILOT DISC circuit breaker (14 VDC aircraft only).
2. Disconnect the electrical connector from the mating connector on the servo as
necessary (1P871 Roll, 2P871 Pitch, 3P871 Pitch Trim, 4P871 Yaw).
3. Remove the servo using the data provided in the appropriate model-specific installation
manual addendum. Refer to the Master Drawing List 005-01009-01.
Reinstallation:
1. Visually inspect the connectors to ensure there are no bent or damaged pins. Repair
any damage.
2. Reinstall the servo using the data provided in the appropriate model-specific installation
manual addendum. Refer to the Master Drawing List 005-01009-01.
3. Reconnect the electrical connector (1P871 for Roll, 2P871 for Pitch, 3P871 for Pitch
Trim, or 4P871 for Yaw, as applicable) to the mating connector on the servo.
4. Perform a functional check of the GSA 87 per Section 7.2
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6.4
GTA 82 Trim Adapter
Removal:
1. Ensure that there is no electrical power to the GTA 82 Trim Adapter by pulling the
AUTOPILOT circuit breaker.
2. Disconnect the electrical connector from the mating connector on the trim adapter
(P821).
3. Remove the GTA 82 using the data provided in the appropriate model-specific
installation manual addendum. Refer to the Master Drawing List 005-01009-01.
Reinstallation:
1. Visually inspect the connector to ensure there are no bent or damaged pins. Repair any
damage.
2. Reinstall the GTA 82 using the data provided in the appropriate model-specific
installation manual addendum. Refer to the Master Drawing List 005-01009-01.
3. Reconnect the electrical connector P821 to the mating connector on the GTA 82.
4. Perform a functional check of the GTA 82 per Section 7.4.
6.5 Air Data Module (ADM)
Removal:
1. Verify that the GFC 600 is de-energized by pulling the AUTOPILOT circuit breaker.
2. Remove the GMC 605 per Section 6.1.
3. Disconnect the pitot and static hoses from the ADM (not required when the ADM is used
as a cabin pressure sensor).
4. Detach the ADM wiring harness from the mating connector on the ADM by depressing
the lock tab and pulling on the connector.
5. Loosen the two attaching screws (in the GMC 605 rack) and slide the ADM to disengage
from the key slot holes in the rack.
Reinstallation:
1. Insert the two screws partially into the ADM.
2. Engage the ADM mounting screws in the key slot holes.
3. Slide the ADM to fully engage the key slots. Note that the ADM screws must be installed
through both the rack and the backplate assembly.
4. Tighten the mounting screws.
5. Connect the ADM wiring harness by lining up the connector and inserting it until the lock
tab engages.
6. Connect the pitot and static hoses to the appropriate ports on the ADM (not required
when the ADM is used as a cabin pressure sensor).
7. Reinstall the GMC 605 per Section 6.1.
8. Perform a functional check of the ADM per Section 7.6.
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9. Perform a functional check of the GMC 605 per Section 7.1.
Figure 6-3 – ADM Installation
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6.6 Configuration Module Removal & Replacement
NOTE
Garmin Configuration Modules are not ESD sensitive. Configuration modules do
not require special ESD protection for handling during installation or maintenance.
Figure 6-4 – Configuration Module Installation
Table 6-1 – Configuration Module Kit
Item
Description
Potted Configuration Module PCB Board Assembly w/EEPROM
& Temp Sensor
Cable, 4-Conductor Harness
Pins, #22 AWG (HD)
1
2
3
Qty Needed
Garmin Part
Number
1
011-02178-00
1
4
325-00122-00
336-00021-00
Removal:
1. De-energize the GFC 600 system by pulling the AUTOPILOT circuit breaker.
2. Remove the GMC 605 per Section 6.1.
3. Loosen the four screws holding the backplate assembly to the rack.
4. Slide the backplate assembly up to disengage the key hole slots in the rack.
5. Remove connector P6052 from the backplate by removing the two attaching screws.
6. Remove the backshell cover from P6052 by removing the two screws.
7. Disconnect the configuration module wiring harness from the configuration module.
8. Remove the configuration module from the backshell.
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Installation:
1. Visually inspect the connector to ensure there are no bent or damaged pins. Repair any
damage
2. Place configuration module in position.
3. Insert connector into configuration module.
4. Assembly of the connector is the reverse of disassembly.
5. Checkout per Section 7.5.
.
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7. Garmin GFC 600 LRU Replacement/Configuration & Testing
This section provides procedures to be followed after a piece of GFC 600 equipment is
replaced. At the beginning of each LRU section, instructions are given to guide the technician
for various removal/replacement scenarios. These instructions define necessary procedures to
be followed for situations where original equipment was reinstalled as well as for situations
where new equipment (new serial number) is installed.
7.1 GMC 605
Original GMC 605 Reinstalled
If the removed GMC 605 is reinstalled, no software or configuration loading is required. This
does not include units that were returned for repair as their software and configuration files are
deleted during the repair testing process. Continue to GMC 605 Test Procedure, Sections 9.3
and 9.4.2.
New Repair or Exchange GMC 605 Installed
If a new, repaired or exchanged GMC 605 is installed, the correct software must be loaded to
the unit. Refer to Section 8.1 for software loading procedures. If the configuration module or
ADM is left in place, no configuration is necessary. Continue to the GMC 605 Test Procedure,
Section 9.3 and 9.4.2.
7.2 GSA 87 Servo
Original GSA 87 Reinstalled
No software/gains loading is required if the removed GSA 87 is re-installed. This does not
include units that were returned for repair as their software and gains files are deleted during the
repair testing process. Continue to the applicable GSA 87 Test Procedure for the servo that
was replaced:
Section 9.3 and 9.4.1.1 for Roll Servo
Section 9.3 and 9.4.1.2 for Pitch Servo
Section 9.3 and 9.4.1.3 for Pitch Trim Servo
Section 9.3 and 9.4.1.4 for Yaw Damper Servo
New, Repaired or Exchange GSA 87 Installed
If a new, repaired or exchanged GSA 87 is installed, the correct software and gains files must
be loaded to the unit. Refer to Section 8.1 for software loading procedures. Continue to the
applicable GSA 87 Test Procedure for the servo that was replaced:
Section 9.3 and 9.4.1.1 for Roll Servo
Section 9.3 and 9.4.1.2 for Pitch Servo
Section 9.3 and 9.4.1.3 for Pitch Trim Servo
Section 9.3 and 9.4.1.4 for Yaw Damper Servo.
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7.3 GI 285 AFCS Mode Annunciator
Original GI 285 Reinstalled
No software or configuration loading is required for the GI 285. Continue to the return-to-service
checks in Section 9.3.
New, Repaired or Exchange GI 285 Installed
If a new, repaired or exchange GI 285 is installed, perform the return to service checks in
Section 9.3.
7.4
GTA 82 Trim Adapter
Original GTA 82 Reinstalled
No software or configuration loading is required for the GTA 82. Continue to the return-toservice checks in Section 9.3 and 9.4.2.
New, Repaired or Exchange GTA 82 Installed
If a new, repaired or exchange GTA 82 is installed, the correct software and gains files must be
loaded to the unit. Refer to Section 8.1 for software loading procedures. Continue to Section
9.3 for the return to service procedure.
7.5 Configuration Module
Original Configuration Module Reinstalled
No configuration is required if the removed configuration module is re-installed. Continue to the
return-to-service checks in Section 9.3 and 9.4.2.
New, Configuration Module Installed
If a new configuration module is installed, the system must be reconfigured in accordance with
Section 8.3 using the original configuration data that is kept with the aircraft permanent records.
Continue to Section 9.2, 9.3, and 9.4.2 for return to service tests.
7.6 Air Data Module (ADM)
Original ADM is Reinstalled
No configuration is required if the removed ADM is re-installed. Perform a pitot/static system
leak check in accordance with Section 9.1 if the pitot/static lines were disconnected. Continue
to Section 9.3 and 9.4.2 for return to service tests.
New ADM is Installed
If a new ADM is installed, the system must be reconfigured in accordance with Section 8.3 using
the original configuration data that is kept with the aircraft permanent records. Perform a
pitot/static leak check in accordance with Section 9.1 . Continue to Sections 9.2, 9.3, and 9.4.2
for return to service tests.
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8. GFC 600 Software Load and Configuration Procedures
NOTE:
To start the GMC 605 in configuration mode, ensure the system is de-energized, then press and
hold the FD button while applying power to the system. Release the FD button when the splash
screen is displayed. Press the HDG button when CONT is displayed on the GMC 605.
Use the NOSE UP/DN thumbwheel on the GMC 605 to scroll up and down through the page
selections. Use the IAS and VS buttons on the GMC 605 to move the cursor to the left or right,
respectively. The VS button is also used to accept the desired selections.
8.1 GMC 605 and GSA 87 Software Loading
NOTE: For aircraft that utilize a GTA 82 Trim Adapter, the items applicable to the GTA 82 will
be loaded during this process.
1. Go to the Dealer Resource Center at www.garmin.com and download the appropriate
software loader image as specified on the Equipment List, 005-01009-05.
2. Execute the file to load the software to a USB flash drive.
3. Ensure that power is not applied to the GMC 605 by pulling the AUTOPILOT circuit
breaker.
4. Connect the USB flash drive to the GMC 605 using a USB adapter cable (p/n 32000726-00 or 320-00726-01).
5. Press and hold the HDG button on the GMC 605 while applying power to the GMC 605.
6. When the splash screen appears, release the HDG button.
7. Remove power from the GMC 605 by pulling the AUTOPILOT circuit breaker.
8. Start the GMC 605 in configuration mode.
9. Navigate to the SYS -> SW UPLOAD page.
10. Start the software upload process. When the software upload process is complete, a
results screen will display. Press HDG to continue.
11. The GMC 605 will restart in normal mode. After the GMC 605 restarts, verify that the
version number in the lower right corner of the splash screen matches the version
number on the equipment list, 005-01009-05.
12. Remove the USB adapter cable and flash drive from the GMC 605.
13. Press HDG to continue from the splash screen.
14. Verify that the unit passes PFT, and does not display a MANIFEST message on the
screen.
8.2 GI 285 Software
The GI 285 comes preloaded with the correct software and is not field loadable. No load
procedure is required.
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8.3 GFC 600 System Configuration
Configure the GFC 600 AFCS to the original configuration settings which are retained with the
aircraft permanent records. Additionally, it is required that all interfaced units be configured to
the original configuration settings which are retained with the aircraft permanent records.
Each configuration item is saved to the configuration module or ADM (if installed) as it is made.
When the configuration item is selected by pressing the VS button to accept the value, the new
value is stored in the configuration module or ADM at that time.
The following is a block diagram of the GMC 605 configuration pages:
Figure 8-1 – Configuration Pages Block Diagram
NOTE:
To start the GMC 605 in configuration mode, ensure the system is de-energized, then press and
hold the FD button while applying power to the system. Release the FD button when the splash
screen is displayed. Press the HDG button when CONT is displayed on the GMC 605.
Use the NOSE UP/DN thumbwheel on the GMC 605 to scroll up and down through the page
selections. Use the IAS and VS buttons on the GMC 605 to move the cursor to the left or right,
respectively. The VS button is also used to accept the desired selections.
Only the SYS -> INSTALL, GMC DSP, RMT DSP, and GFC -> CALIBRATE pages are used for
configuring the system. All of the other pages displayed while in configuration mode provide
system information that is useful for maintenance and troubleshooting.
To exit configuration mode, cycle power to the GFC 600 system.
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Configure the system using the following sections when the configuration module or ADM is
replaced.
8.3.1 SYS -> INSTALL Pages
1. Navigate to the SYS -> INSTALL pages on the GMC 605.
2. Move the cursor through each of the following configuration items on INSTALL page 1/3
to make the appropriate selections:
Configuration Item
Setting
Notes
PTRM
YES or NO
Select YES if the installation includes a pitch
trim servo. Otherwise, select NO.
YAW DAMPER
YES or NO
Select YES if the installation includes a yaw
damper servo. Otherwise, select NO.
GI 285
YES or NO
Select YES if the installation includes a GI 285
remote mode annunciator panel. Otherwise,
select NO.
HSI/DG
NO, GDU, KI525,
CENT NSD,
52D54, or G502A
Select NO if the system is interface to a
Garmin GDU, or if the installation does not
include an HSI or DG interface.
Select GDU if the system is interfaced to a
Garmin GDU.
Select KI525 if the system is interfaced to a
KI-525A, Aspen EFD1000, or Sandel SN 3500
or SN 4500, or G5 HSI.
Select CENT NSD if the system is interfaced
to a Century NSD 360 or NSD 1000.
Select 52D54 if the system is interfaced to an
EDO Aire 52D54 or Sigmatek 4000C Series
directional gyro. Refer to the manufacturer’s
data to determine equivalency for specific
dash numbers
Select G502A if the system is interfaced to an
ARC G502A or Sigmatek 4000D or 4000H
series directional gyro. Refer to the
manufacturer’s data to determine equivalency
for specific dash numbers.
3. Select INSTALL page 2/3.
4. Move the cursor through each of the configuration items on page 2/3 to set the following
configuration items:
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Configuration Item
Setting
Notes
FLT DIR
NO, GDU, ASPEN,
G5
Select NO if the system is not interfaced to a
flight director.
Select GDU if the system is interfaced with a
Garmin GDU.
Select ASPEN if the system is interfaced with
and Aspen EFD.
Select G5 if the system is interfaced to a
Garmin G5.
GPS ROLSTR
YES or NO
Select YES if ARINC 429 or HSDB roll
steering is provided directly to the GMC 605.
Otherwise, select NO.
GPS DEV
ANGULR or
LINEAR
Select ANGULR for any TSO-C146 (WAAS)
GPS
Select LINEAR for any non-WAAS GPS.
VNAV
YES or NO
Select YES is interfaced to a system capable
of EDO VNAV.
Select NO if not interfaced to a system
capable of EDO VNAV.
EDO VNAV requires GMC 605 version 2.20 or
later and interface to a Garmin GDU
620/7XX/1060 or Garmin G5.
5. Select INSTALL page 3/3.
6. Move the cursor through each of the configuration items on page 3/3 to set the following
configuration items:
Configuration Item
Setting
Notes
COL SNSR
NONE, LVDT, POT
Select NONE.
CBN PRSSR
NONE, ADM
Select NONE if there is no cabin pressure
sensor required.
Select ADM if an ADM is being utilized as a
cabin pressure sensor.
Refer to the equipment list (005-01009-05) to
determine if the cabin pressure function is
available for the airframe.
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8.3.2 GMC DISP Pages
NOTE: Make sure that the GMC 605 display and key brightness levels match the lighting levels
of other equipment in the instrument panel under night lighting conditions.
1. Go to the GMC DSP -> BACKLIGHT page. See below for representative image.
2. Move the cursor through each of the following configuration items and make the
appropriate selections:
Configuration Item
Setting
Notes
SOURCE
PHOTOCELL, 14 VDC, 28
VDC, 5 VDC, 5 VAC
Select PHOTOCELL if the lighting
level uses ambient lighting for
photocell dimming, otherwise select
the appropriate lighting bus voltage.
TRANSITION
0 – 100
Sets the minimum lighting bus
threshold at which the display
switches from the lighting bus source
to the photocell. This setting is not
applicable when the SOURCE is set
to PHOTOCELL.
The current backlight source is shown in the box at the right side beside the heading “SRC”.
The “I” field displays the lighting input level as a percentage. The “O” field displays the lighting
output level as a percentage.
3. Go to the GMC DSP > LIGHTBUS > DISP > 1/2 and 2/2 and the GMC DSP >
LIGHTBUS > KEYS > 1/2 and 2/2 pages. See below for representative images.
4. Move the cursor through each of the fields and make the appropriate selections:
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(KEYS pages are similar to the above)
These pages display and allow the setting of the points on the lighting bus response curve,
using four set points. Each of the four input values (X1, X2, X3, and X4) have a corresponding
output value (Y1, Y2, Y3, and Y4). All values are percentages of the full range.
X1 is always set to 0 (percent) and X4 is always set to 100 (percent), but X2 and X3 can be set
to any point between, as long as X2 is greater than X1, X3 is greater than X2, and X4 is greater
than X3.
Similarly, each output value must be larger than (or equal to) the previous output such that Y4 is
greater than or equal to Y3, Y3 is great than or equal to Y2, and Y2 is greater than or equal to
Y1.
The status box is similar to that on the GMC DSP > BACKLGHT page.
The right side of the screen provides a visual representation of the curve set by the four X and
four Y values. It will update as the values are changed.
5. Go to the GMC DSP -> PHOTOCEL >DISP > 1/2 and 2/2 and the GMC DSP >
PHOTOCEL > KEYS > 1/2 and 2/2 pages.
6. Move the cursor through each of the configuration items and make the appropriate
selections in a method similar to that for the GMC DSP > LIGHTBUS pages.
7. Go to the GMC DSP -> CONTRAST page.
8. Move the cursor through each of the following configuration items and make the
appropriate selections.
Configuration Item
Setting
Notes
OFFSET
-50 - 50
Manually configures the default
contrast offset value from -50 to 50.
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8.3.3 RMT DISP Pages
The following procedures must be completed when a GI 285 AFCS Mode Annunciator Panel is
installed. Skip this section if a GI 285 is not installed.
NOTE: Make sure that the GMC 605 display and key brightness levels match the lighting levels
of other equipment in the instrument panel under night lighting conditions.
1. Go to the RMT DSP -> BACKLIGHT page.
2. Move the cursor through each of the following configuration items and make the
appropriate selections.
Configuration Item
Setting
Notes
SOURCE
PHOTOCELL, 14 VDC, 28
VDC, 5 VDC, 5 VAC
Select PHOTOCELL if the lighting level
uses ambient lighting, otherwise select
the appropriate lighting bus voltage.
TRANSITION
0 – 100
Sets the minimum lighting bus
threshold at which the display switches
from the lighting bus source to the
photocell. This setting is not applicable
when the SOURCE is set to
PHOTOCELL
3. Go to the RMT DSP -> LIGHTBUS > 1/2 and 2/2 pages.
4. Move the cursor through each of the configuration items and make the appropriate
selections. The available settings are similar to those for the GMC DSP pages, except
in the status box, the input “I” and output “O” values are not displayed.
5. Go to the RMT DSP -> PHOTOCEL > 1/2 and 2/2 pages.
6. Move the cursor through each of the configuration items and make the appropriate
selections. The available settings are similar to those for the GMC DSP pages, except
in the status box, the input “I” and output “O” values are not displayed.
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9. GFC 600 Return to Service Procedure
The following sections will verify the proper operation of the GFC 600 AFCS after maintenance
has been performed on the system. Operational information regarding the GFC 600 AFCS can
be found in the GFC 600 Pilot’s Guide, p/n 190-01488-00.
9.1 Pitot and Static System Leak Check
If an Air Data Module (ADM) is installed in the system and is not being used as a Cabin
Pressure sensor or if the pitot and/or static system were opened during maintenance, a pitot
and static system leak check must be performed. Refer to the aircraft maintenance manual for
pitot and static system leak test instructions.
NOTE: Disable any ADS-B Transmitting equipment for this test to avoid interference with air
traffic control.
9.2 Configuration Mode Tests
Perform the following tests if the configuration module (or ADM) is replaced, or when the GMC
605 rack is removed or loosened.
9.2.1 Pitch/Roll Offset Calibration
NOTE: Level the aircraft in accordance with the manufacturer’s aircraft maintenance manual
prior to applying external electrical power to the aircraft, existing avionics systems, and GFC
600 AFCS and starting the Pitch/Roll offset calibration test.
NOTE: Use the NOSE UP/DN thumbwheel on the GMC 605 to scroll up and down through the
page selections. Use the IAS and VS buttons on the GMC 605 to move the cursor left or right,
respectively. The VS button is also used to accept the desired selections.
NOTE: To exit configuration mode, cycle power to the GFC 600 system.
1. Start the GMC 605 in configuration mode by pressing and holding the FD button while
applying power to the system. Press the HDG button when CONT is displayed on the
GMC 605.
2. Navigate to the GFC -> CALIBRATE -> PITCH/ROLL page.
3. Scroll through each of the pitch/roll calibration pages, following the instructions on each
page to ensure that the system is ready for calibration.
4. Select BEGIN CALIBRATION to start the calibration process.
5. When the test is complete, select QUIT to return to the GFC -> CALIBRATE ->
PITCH/ROLL page.
NOTE: STATUS -> TEST IN PROGRESS will be displayed while the pitch and roll offset is
being calibrated.
NOTE: Select QUIT to quit the calibration process if necessary.
NOTE: TEST COMPLETE: SUCCESS will be displayed if the process completes successfully.
NOTE: TEST COMPLETE: FAILURE will be displayed if the process does not complete
successfully. Refer to Section 5.1 for troubleshooting tips.
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9.2.2 Engine Run-Up Test
WARNING:
Ensure that the aircraft is outside in a location where the engine(s) can be run safely. Make
sure that all equipment and personnel are clear of the engine(s) and/or propeller(s) before
proceeding with these tests.
1. With engine(s) running, and avionics powered, start the GMC 605 in configuration mode
by pressing and holding the FD button while applying power to the GMC 605. Press the
HDG button when CONT is displayed on the GMC 605.
2. Navigate to the GFC -> CALIBRATE -> ENGINE page.
3. Scroll through each of the engine run-up pages, following the instructions on each page
to ensure that the system is ready for calibration.
4. Select BEGIN RUN-UP TEST to start the engine run-up test.
NOTE: TEST IN PROGRESS. PRESS COMPLETE WHEN FINISHED will be displayed while
the engine run-up test is in progress.
5. Select COMPLETE when the test procedures have been completed.
6. Select GET RESUL to view the test results.
7. After viewing the test results, select QUIT to return to the GFC -> CALIBRATE ->
ENGINE page.
8. Shut down the engine(s) in accordance with the appropriate airplane flight manual
(AFM), airplane flight manual supplement (AFMS), or pilot’s operating handbook (POH).
NOTE: Select QUIT to quit the engine run-up test if necessary.
NOTE: If a TEST COMPLETE: FAILURE message is displayed, refer to Section 5.1 for
troubleshooting tips.
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9.3 Pre-Flight Test (PFT)
Pre-Flight Test (PFT) is accomplished automatically by the GFC 600 AFCS after the system is
powered up in normal mode and after the splash screen is acknowledged.
1. Apply electrical power to the aircraft.
2. After the GMC 605 displays the splash screen, push the HDG button to continue to
normal mode operation.
3. Verify the following events occur during PFT.
a. GMC displays PFT on the display
b. GDU (if installed) displays PFT in black text on a white background at the top of
the display
c. The three LED’s on the face of the GMC 605 (next to the AP, FD, and YD
buttons) are illuminated yellow for one second, then red for one second.
d. The GI 285 (if installed) illuminates all lateral mode annunciations in yellow for
one second, followed by AP/YD/TRIM annunciations for one second, the all
vertical mode annunciations in yellow for one second, then AP/YD/TRIM
annunciations in red for one second.
4. Verify the following occur at the conclusion of PFT.
a. Normal autopilot disconnect tone (two high-low tones approximately two seconds
in duration) is played through the cockpit speaker and headphones.
b. PFT is removed from the GMC 605 and GDU (if installed).
c. ESP roll indices are displayed at the appropriate left and right roll attitude on the
GDU (if installed). Refer to the appropriate model-specific installation manual
addendum for model specific information on the placement of the roll indices.
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9.4 Normal Mode Tests
The tests in the following sections are performed with the system in normal mode.
NOTE: Throughout the following sections:
1. A normal autopilot disconnect will be accompanied by a normal disconnect aural alert
(two high-low tones approximately two seconds in duration) through the cockpit
speaker(s) and headphones and a continuous tone from the sonalert for approximately
10 seconds (if installed).
2. An abnormal disconnect will be accompanied by an abnormal disconnect aural alert
(continuous high-low tones) through the cockpit speaker(s) and headphones and a
continuous tone from the sonalert (if installed). The abnormal disconnect tones can be
cancelled by pressing the AP button on the GMC 605 or the AP DISC/TRIM INT switch
on the pilot’s flight controls.
3. GFC 600 AFCS mode and status annunciations are displayed on the PFD only if the
PFD is a Garmin GDU.
4. If the aircraft does not have a GI 285 AFCS mode annunciator, disregard any steps
calling on the GI 285.
5. If the aircraft is not equipped with a flight director, disregard any steps for flight director
command bars.
6. If the aircraft is not equipped with a pitch trim servo, disregard the steps for pitch trim
servos.
7. If the aircraft is not equipped with a yaw damper servo, disregard the steps for yaw
damper servos.
8. Depending on the aircraft and the control system, the pitch trim may run automatically at
any time while the autopilot is engaged. If it gets to the end of its travel, an amber TRIM
annunciation may appear. If this is causing undesirable results, press and hold the CWS
switch while manually operating the aircraft trim wheel in the opposite direction. Release
the CWS switch when the trim wheel is no longer on its stop.
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9.4.1 Servo Tests
If a servo has been removed and reinstalled (or replaced), perform the following steps.
1. Load software as shown in Section 8.1.
2. Power the GFC 600 in normal mode.
3. Complete Pre-Flight Test (PFT) as shown in Section 9.2.
4. Proceed to the sub-section below as appropriate for the servo that has been replaced.
9.4.1.1
Roll Servo Functional Check
1. Verify that the steps in Section 9.4.1 have been completed.
2. Center the heading bug on the aircraft heading.
3. Engage the autopilot by pressing the AP button on the GMC 605.
4. Verify that the roll servo is restricting free movement of the flight controls.
5. Press the HDG button to engage roll mode.
6. Rotate the heading bug to the left of the current aircraft heading.
7. Ensure that the command bars indicate a left roll and that the servo drives the flight
controls to the left.
8. Rotate the heading bug to the right of the current aircraft heading.
9. Ensure that the command bars indicate a right roll and that the servo drives the flight
controls to the right.
10. Firmly grasp the control wheel and press the AP DISC/TRIM INT switch on the pilot’s
flight controls.
11. Verify that the roll control moves freely.
9.4.1.2
Pitch Servo Functional Check
1. Verify that the steps in Section 9.4.1 have been completed.
2. Center the flight controls approximately mid-travel.
3. Engage the autopilot by pressing the AP button on the GMC 605.
4. Verify that the pitch servo is restricting free movement of the flight controls.
5. Rotate the NOSE UP/DN thumbwheel UP three clicks.
6. Ensure that the flight director command bars indicate a pitch up and that the pitch servo
drives the controls in a nose up direction. NOTE: In some aircraft, some assistance may
be needed to drive the flight controls against any counterweight or springs.
7. Press and release the CWS switch to recenter the pitch reference.
8. Apply continuous forward pressure on the pitch control in a nose down direction.
9. Ensure that the pitch trim (if installed) begins running in the nose up direction.
10. Press and release the CWS switch to recenter the pitch reference.
11. Apply continuous aft pressure to the flight controls in a nose up direction.
12. Ensure that the pitch trim (if installed) begins running in the nose down direction.
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13. Press and release the CWS switch to recenter the pitch reference.
14. Rotate the NOSE UP/DN thumbwheel DN three clicks.
15. Ensure that the flight director command bars indicate a pitch down and that the pitch
servo drives the controls in a nose down direction.
16. Firmly grasp the control wheel and press the AP DISC/TRIM INT switch on the pilot’s
flight controls.
17. Verify that the pitch control moves freely.
9.4.1.3
Pitch Trim Servo Functional Check (If Installed)
NOTE: For installations with dual flight control switch installations, repeat the flight control
switch checks for the copilot flight controls.
1. Verify that the steps in Section 9.4.1 have been completed.
2. Depress both halves of the PITCH TRIM switch on the pilot’s flight controls in the NOSE
UP direction.
3. Verify that the trim runs in the nose up direction.
4. While the trim is running, depress the AP DISC/TRIM INT switch on the pilot’s flight
controls and verify that the pitch trim stops running.
5. Depress both halves of the PITCH TRIM switch on the pilot’s flight controls in the NOSE
DN direction.
6. Verify that the trim runs in the nose down direction.
7. Manually adjust the trim all the way to the nose down stop.
8. While monitoring elapsed time, actuate both halves of the PITCH TRIM Switch on the
pilot’s flight controls in the NOSE UP direction until the trim runs against the nose up
mechanical stop.
9. Verify that the elapsed time for full travel of the pitch trim is within the tolerances
specified in the appropriate model-specific installation manual addendum (190-01937XX).
10. While monitoring elapsed time, actuate both halves of the PITCH TRIM Switch on the
pilot’s flight controls in the NOSE DN direction until the trim runs against the nose down
mechanical stop.
11. Verify that the elapsed time for full travel of the pitch trim is within the tolerances
specified in the appropriate model-specific installation manual addendum (190-01937XX).
9.4.1.4
Yaw Damper Functional Check (If Installed)
1. Verify that the steps in Section 9.4.1 have been completed.
2. Engage the Yaw Damper by pressing the YD button on the GMC 605.
3. Verify that resistance is felt in the rudder pedals.
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9.4.2 GFC 600 Functional Checks
Perform the following test procedures when the configuration module (or ADM) is replaced or
when the GMC 605 is replaced.
9.4.2.1
AFCS Switch Checks
NOTE: For installations with dual flight control switch installations, repeat the flight control
switch checks for the copilot flight controls.
1. If the GMC 605 was replaced, load the software in accordance with Section 8.1.
2. Power up the system in normal mode.
3. Complete Pre-Flight Test (PFT) as shown in Section 9.2.
4. Actuate both halves of the PITCH TRIM switch on the pilot’s flight controls in the nose
down (forward) direction.
5. Verify that the Pitch Trim Servo engages and drives the airplane trim system in a Nose
Down direction.
6. Release the PITCH TRIM Switch.
7. Actuate both halves of the PITCH TRIM switch on the pilot’s flight controls in the nose up
(aft) direction.
8. Verify that the Pitch Trim Servo engages and drives the airplane trim system in a Nose
Up direction.
9. Release the PITCH TRIM switch.
10. Engage the Autopilot by pressing the AP button on the GMC 605.
11. Actuate the left half of the PITCH TRIM switch in the nose down (forward) direction.
12. Verify that the Autopilot disengages, as evidenced by the following:
a. Normal Autopilot disconnect tone is played through the speakers and headsets.
b. Continuous tone played through the Sonalert for approximately 10 seconds.
c. Flashing yellow LED is illuminated next to the AP button on the GMC 605 for
approximately 10 seconds.
d. Flashing yellow AP on the GI 285 for approximately 10 seconds.
e. Flashing yellow AP on the PFD for approximately 10 seconds.
13. Engage the Autopilot by pressing the AP button on the GMC 605.
14. Actuate the left half of the PITCH TRIM switch in the nose up (aft) direction.
15. Verify that the Autopilot disengages.
16. Engage the Autopilot by pressing the AP button on the GMC 605.
17. Actuate the right half of the PITCH TRIM switch in the nose down (forward) direction.
18. Verify that the Autopilot disengages.
19. Engage the Autopilot by pressing the AP button on the GMC 605.
20. Actuate the right half of the PITCH TRIM switch in the nose up (aft) direction.
21. Verify that the Autopilot disengages.
22. Engage the Autopilot by pressing the AP button on the GMC 605.
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23. Press and hold the CWS Switch.
24. Verify the following:
a. CWS ON is displayed on the GMC 605.
b. The green LED next to the AP button on the GMC 605 begins flashing.
c. The white AP is displayed in place of the green AP on the GI 285.
d. White CWS is displayed in place of the green AP on the PFD.
e. Flight Controls move freely in the pitch and roll axes.
25. Release the CWS Switch.
26. Press the AP DISC/TRIM INT switch on the pilot’s flight controls.
27. Verify that the autopilot disengages.
28. Engage the Autopilot by pressing the AP Button on the GMC 605.
29. Press the AP button on the GMC 605.
30. Verify that the autopilot disengages but the YD remains engaged.
31. Press the GO AROUND switch.
32. Verify the following:
a. GA is annunciated for both lateral and vertical modes on the GMC 605.
b. GA is annunciated for both lateral and vertical modes on the GI 285.
c. GA is annunciated for both lateral and vertical modes on the PFD.
d. The green LED next to the FD button on the GMC 605 is illuminated.
e. The flight director command bars are displayed and indicate wings level and
pitch up to the angle as shown on the appropriate Install Manual Addendum
(190-01937-XX).
33. Press the FD button on the GMC 605.
34. Verify that the LED next to the FD button on the GMC 605 extinguishes and that the
flight director command bars are no longer displayed.
35. Press and hold the AP DISC/TRIM INT Switch for at least 5 seconds.
36. Verify the ESP OFF message appears on the GMC 605.
37. Engage the autopilot by pressing the AP button on the GMC 605.
38. Verify that the ESP OFF message is removed from the GMC 605.
39. Disengage the autopilot by pressing the AP DISC/TRIM INT switch on the pilot’s flight
controls.
9.4.2.2
Manual Electric Pitch Trim Speed Check
NOTE: For installations with dual flight control switch installations, repeat the flight control
switch checks for the copilot flight controls.
1. Manually adjust pitch trim fully against either mechanical stop.
2. Actuate the PITCH TRIM switch on the pilot’s flight controls until the trim runs against
the other mechanical stop while monitoring the run time.
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3. Verify that the elapsed time for full travel of the pitch trim is within the range specified on
the appropriate model-specific installation manual addendum (190-01937-XX).
4. Repeat the test in the opposite direction.
9.4.2.3
Interface Checks
NOTE: For systems that are interfaced to a Garmin GDU, ALTS and the selected altitude (in
FT) will be displayed on the GMC, and ALTS will be displayed in white on the PFD. These
annunciations are separately tested in Section 9.4.2.12 and may be ignored in all other sections
of these procedures.
NOTE: For installations with dual flight control switch installations, repeat the flight control
switch checks for the copilot flight controls.
NOTE: If the aircraft under test does not have a LOW BANK Switch installed, those steps may
be skipped.
1. Set the heading bug to the current aircraft heading.
2. Engage the autopilot by pressing the AP button on the GMC 605.
3. Verify that ROL and PIT are displayed on the GMC 605 and that the green LED’s next to
the AP, FD, and YD buttons illuminate.
4. Verify that ROL, AP, YD, and PIT are displayed in green on the PFD and on the GI 285.
5. Verify that the flight director command bars are displayed in level pitch and roll attitude.
6. Press the HDG button on the GMC 605 to engage heading mode.
7. Verify that HDG replaces ROL on the GMC 605, the PFD, and the GI 285.
8. Press the LOW BANK switch on the instrument panel to engage low bank mode.
9. Verify that LOW BANK is annunciated on the GMC 605.
10. Press the LOW BANK switch on the instrument panel to disengage low bank mode.
11. Verify that the LOW BANK annunciation is removed from the GMC 605.
12. Adjust the heading bug to the left of the aircraft heading.
13. Verify that the flight director command bars indicate a left turn, and that the flight controls
move toward the left.
14. Adjust the heading bug to the right of the aircraft heading.
15. Verify that the flight director command bars indicate a right turn, and that the flight
controls move toward the right.
16. Center the heading bug at the aircraft heading.
17. Press and hold the CWS switch.
18. Center the aircraft pitch control while continuing to hold the CWS switch.
19. Release the CWS switch.
20. Click the NOSE UP/DN thumbwheel to the UP position four times.
21. Verify that the command bars indicate a fly up command and that the flight controls drive
in the pitch up direction. NOTE: In some aircraft, it may be necessary to counteract any
counterweight or control system springs to assist the servo.
22. Press and hold the CWS switch.
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23. Center the aircraft pitch control while continuing to hold the CWS switch.
24. Release the CWS switch.
25. Click the NOSE UP/DN thumbwheel to the DN position four times.
26. Verify that the command bars indicate a fly down command and that the flight controls
drive in the pitch down direction.
27. Press and release the CWS switch.
28. Press the AP DISC/TRIM INT switch to disengage the autopilot.
9.4.2.4
Lighting Check
1. Darken the cockpit to simulate night lighting conditions.
2. Press the AP button on the GMC 605 to engage the autopilot.
3. Operate the dimming bus control to which the GMC 605 is connected.
4. Verify that the display and key lighting remains visible throughout the full range of the
dimmer control.
5. If a GI 285 is installed, operate the dimming bus control to which the GI 285 is
connected.
6. Verify that the annunciations on the GI 285 remain visible through the full range of the
dimmer control.
7. Verify that the GMC display and key lighting and GI 285 annunciation light intensities are
as close as possible to the intensities of existing equipment in the panel that are
operated by the same dimmer control(s).
8. Press the AP DISC/TRIM INT switch to disengage the autopilot.
9.4.2.5
VOR Mode Check
1. Set the Course pointer on the CDI 15 degrees to the left of aircraft heading and ensure
that the CDI is displaying VOR navigation information.
2. Simulate a VOR signal with a “TO” course equal to the aircraft heading.
3. Engage the autopilot by pressing the AP button on the GMC 605.
4. Verify ROL and PIT are displayed on the GMC 605.
5. Press the NAV button on the GMC 605.
6. Verify VOR is displayed below ROL on the GMC 605.
7. Verify that VOR is displayed in white with ROL, AP, YD, and PIT in green on the PFD
and GI 285.
8. Verify that the flight director command bars are displayed in level pitch and roll attitude.
9. Slowly adjust the course pointer on the CDI toward the aircraft heading.
10. When the course pointer is approximately five degrees away from aircraft heading, verify
that VOR replaces ROL on the GMC 605, that VOR displays green on the PFD and GI
285 and that ROL is not displayed on the PFD and GI 285.
11. Center course pointer on the aircraft heading.
12. Adjust the simulated course and the aircraft course pointer 20 degrees to the left of
current aircraft heading.
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13. Verify that the flight director command bars indicate a left turn and that the flight controls
move toward a left turn.
14. Adjust simulated course to aircraft heading.
15. Press and hold the CWS switch while recentering the flight controls.
16. Adjust the simulated course on the nav test set and the aircraft course pointer 20
degrees to the right of current aircraft heading.
17. Verify that the flight director command bars indicate a right turn and that the flight
controls move toward a right turn.
18. Adjust the simulated course to aircraft heading.
19. Press the NAV button on the GMC 605.
20. Verify ROL and PIT are displayed on the GMC 605, GI 285, and PFD.
21. Press the APR button.
22. Verify VAPP displays on the GMC 605 in place of ROL.
23. Disengage the autopilot.
9.4.2.6
GPS Mode Check
1. On the GPS Navigator, enter a Direct-To flight plan to an airport that is generally in front
of the aircraft.
2. Ensure GPS is displayed on the CDI.
3. Engage the autopilot by pressing the AP button on the GMC 605.
4. Verify that ROL and PIT are displayed on the GMC 605.
5. Press the NAV button on the GMC 605.
6. Verify that GPS replaces ROL on the GMC 605, GI 285, and PFD.
7. Select OBS mode on the GPS navigator.
8. Adjust the OBS 3 degrees higher than the current DTK (Example: If the DTK is 272
degrees, adjust the OBS to 275 degrees).
9. Verify that the CDI moves to the left.
10. Verify that the flight director command bars indicate a left turn and that the flight controls
drive to the left.
11. Adjust the OBS three degrees lower than the current DTK.
12. Verify that the CDI moves to the right.
13. Verify that the flight director command bars indicate a right turn and that the flight
controls drive to the right.
14. Press the AP DISC/TRIM INT Switch to disengage the autopilot.
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9.4.2.7
ILS APR (including LOC/BC) Checks
1. Simulate an ILS (Localizer and Glideslope) using a ramp tester.
2. Tune the NAV radio to the Localizer frequency
3. Set the CDI to display the ILS.
4. Set the signal generator to simulate 0.093 DDM Left and 0.091 DDM Up signals.
5. Adjust the course pointer to aircraft heading.
6. Engage the autopilot by pressing the AP button on the GMC.
7. Verify ROL and PIT are displayed on the GMC, GI 285, and PFD.
8. Press the APR button on the GMC 605.
9. Verify LOC and GS are the armed modes (smaller text below ROL and PIT on the GMC,
and in white on the GI 285 and PFD).
10. Slowly center the LOC deviation on the test set.
11. Verify that LOC replaces ROL on the GMC 605 and LOC turns green and ROL is
extinguished on the GI 285 and PFD.
12. Slowly center the GS deviation on the test set.
13. Verify that GS replaced PIT on the GMC 605 and GS turns green and PIT is
extinguished on the GI 285 and PFD.
14. Apply left LOC deviation on the test set.
15. Verify that the flight director command bars indicate a left turn and that the flight controls
turn to the left.
16. Apply right LOC deviation on the test set.
17. Verify that the flight director command bars indicate a right turn and that the flight
controls turn to the right.
18. Apply up GS deviation on the test set.
19. Verify that the flight director command bars indicate a pitch up and that the flight controls
drive in the pitch up direction.
20. Apply down GS deviation on the test set.
21. Verify that the flight director command bars indicate a pitch down and that the flight
controls drive in the pitch down direction.
22. Press the AP DISC/TRIM INT switch to disengage the autopilot.
9.4.2.8
VNV Check
1. If VNAV option is not enabled, press the VNV key on the GMC 605.
2. Verify that DISABLD KEY appears on the GMC 605.
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9.4.2.9
IAS Mode Check
An air data test set is required for this section
NOTE: Disable any ADS-B Transmitting equipment for this test to avoid interference with air
traffic control.
1. Set the air data test set to 3000 ft. altitude and 120 kts airspeed.
2. Engage the autopilot by pressing the AP button on the GMC 605.
3. Verify ROL and PIT are displayed on the GMC 605.
4. Press the IAS button on the GMC 605.
5. Verify IAS replaces PIT on the GMC 605 and that IAS is displayed in green and PIT
extinguishes on the GI 285 and PFD.
6. Verify that 120 KT (+/- 2 KT) is displayed on the GMC 605.
7. Rotate the NOSE UP/DN thumbwheel UP until 100 KT is displayed on the GMC 605
8. Verify that the flight director command bars indicate a pitch up command and the flight
controls respond in a nose up direction.
9. Rotate the NOSE UP/DN thumbwheel DN until 140 KT is displayed on the GMC 605
10. Verify that the flight director command bars indicate a pitch down command and the
flight controls respond in a nose down direction.
11. Rotate the NOSE UP/DN thumbwheel UP until 120 KT is displayed on the GMC 605
12. Verify that the flight director command bars indicate level pitch attitude.
13. Adjust the air data test set for 100 kts airspeed.
14. Verify that the flight director command bars indicate a pitch down command and the
flight controls respond in a nose down direction.
15. Adjust the air data test set for 140 kts airspeed.
16. Verify that the flight director command bars indicate a pitch up command and the flight
controls respond in a nose up direction.
17. Return the air data test set to 3000 ft. altitude and 120 kts airspeed.
18. Press the IAS button on the GMC 605 to deselect IAS mode.
19. Verify that PIT is displayed in place of IAS on the GMC 605 and that PIT illuminates in
green on the PFD and GI 285 and that IAS is extinguished on the GI 285.
20. Press the AP DISC/TRIM INT switch on the pilot’s flight controls to disengage the
autopilot.
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9.4.2.10 VS Mode Check
NOTE: Disable any ADS-B Transmitting equipment for this test to avoid interference with air
traffic control.
1. Set the air data test set to 3000 ft. altitude and 120 kts airspeed, if not already there.
2. Engage the autopilot by pressing the AP button on the GMC 605.
3. Verify ROL and PIT are displayed on the GMC 605.
4. Press the VS button on the GMC 605 to engage VS mode
5. Verify VS replaces PIT on the GMC 605 and that VS is displayed in green and PIT
extinguishes on the GI 285 and PFD.
6. Verify that 0 FPM is displayed to the right of VS on the GMC 605.
7. Rotate the NOSE UP/DN thumbwheel UP until 1000 FPM is displayed on the GMC
605
8. Verify that the flight director command bars indicate pitch up and the flight controls
respond in the direction of the command bars.
9. Rotate the NOSE UP/DN thumbwheel DN until 1000 FPM is displayed on the GMC
605
10. Verify that the flight director command bars indicate pitch down and the flight controls
respond in the direction of the command bars.
11. Rotate the NOSE UP/DN thumbwheel UP until 0 FPM is displayed on the GMC 605
12. Verify that the flight director command bars indicate level pitch attitude and the flight
controls are centered in pitch and roll.
13. Set the air data test set for 4000 ft. altitude at a vertical speed of 1000 fpm.
14. Verify that the flight director command bars indicate pitch down and the flight controls
respond in the direction of the command bars.
15. Set the air data test set for 2000 ft. altitude at a vertical speed of 1000 fpm.
16. Verify that the flight director command bars indicate pitch up and the flight controls
respond in the direction of the command bars.
17. Set the air data test set for 3000 ft. altitude and 120 kts airspeed.
18. Press the VS button on the GMC 605 to deselect VS mode.
19. Verify that PIT is displayed in place of VS on the GMC 605 and that PIT illuminates in
green on the PFD and GI 285 and that VS is extinguished on the GI 285.
20. Press the AP DISC/TRIM INT switch on the pilot’s flight controls to disengage the
autopilot.
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9.4.2.11 ALT Mode Check
NOTE: Disable any ADS-B Transmitting equipment for this test to avoid interference with air
traffic control.
1. Set the air data test set to 3000 ft. altitude and 120 kts airspeed, if not already there.
2. Press the AP button on the GMC 605 to engage the autopilot.
3. Verify ROL and PIT are displayed on the GMC 605.
4. Press the ALT button on the GMC 605 to select ALT mode.
5. Verify ALT replaces PIT on the GMC 605 and that ALT is displayed in green and PIT
extinguishes on the GI 285 and PFD.
6. Adjust the air data test set for 3500 ft. altitude.
7. Verify that the flight director command bars indicate a pitch down and the flight controls
respond in the direction of the command bars.
8. Adjust the air data test set for 2500 ft. altitude.
9. Verify that the flight director command bars indicate pitch up and the flight controls
respond in the direction of the command bars.
10. Return the air data test set to 3000 ft. altitude and 120 kts airspeed.
11. Press the ALT button on the GMC 605 to deselect ALT mode.
12. Verify that PIT is displayed in place of ALT on the GMC 605 and that PIT illuminates in
green on the PFD and GI 285 and that ALT is extinguished on the GI 285.
13. Press the AP DISC/TRIM INT switch on the pilot’s flight controls to disengage the
autopilot.
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9.4.2.12 ALTS Mode Check
NOTE: Disable any ADS-B Transmitting equipment for this test to avoid interference with air
traffic control.
This check is only applicable to installations where a Garmin GDU is interfaced to the GMC 605.
1. Set the air data test set to 3000 ft. altitude and 120 kts airspeed, if not already there.
2. Set the selected altitude on the PFD to 3500 ft.
3. Press the AP button on the GMC 605 to engage the autopilot.
4. Verify ROL and PIT are displayed on the GMC 605 with ALTS and 3500FT being
displayed below PIT.
5. Verify green ROL, AP, YD, PIT, and white ALTS are displayed on the PFD.
6. Verify green ROL, AP, YD, PIT, and white ALT are illuminated on the GI 285.
7. Adjust the air data test set for 3500 ft. altitude at a vertical speed of 500 fpm.
8. When the altitude reaches 3450 +/- 20 feet, verify the following annunciations and
displays:
a. ALT is flashed for approximately 3 seconds in place of PIT on the GMC 605, then
displays steady, along with 3500 FT.
b. Green ALT 3500 flashes for approximately 3 seconds in place of PIT on the PFD
and then displays steady.
c. Green ALT flashes for approximately 3 seconds on the GI 285 and then is
illuminated steady and PIT is not illuminated.
NOTE
The flight director command bars and flight controls may move up or down as the GFC 600
AFCS is capturing the selected altitude.
9. Adjust the air data test set for 4000 ft. altitude at a vertical speed of 500 fpm.
10. Verify that the flight director command bars indicate a pitch down and the flight controls
respond in the direction of the command bars.
11. Adjust the air data test set for 3000 ft. altitude at a vertical speed of 500 fpm.
12. Verify that the flight director command bars indicate a pitch up and the flight controls
respond in the direction of the command bars when the altitude goes below 3500 ft.
13. Return the air data test set to 3000 ft. altitude and 120 kts airspeed.
14. Allow the air data test set to stabilize at the target altitude and airspeed.
15. Adjust the selected altitude on the PFD to 0 FT.
16. Press the ALT button on the GMC 605 to deselect ALT mode.
17. Verify PIT is displayed place of ALT on the GMC 605 with ALTS 0FT below PIT.
18. Verify green PIT on the PFD and GI 285 and that ALT is not illuminated on the GI 285.
19. Press the AP DISC/TRIM INT switch on the pilot’s flight controls to disengage the
autopilot.
20. Return the air data test set to field elevation and 0 kts airspeed.
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9.4.2.13 LVL Mode Check
Perform steps 1 through 13 if there is a flight director interface installed. If there is no flight
director interface installed, skip to Step 14 of this section.
1. Set the heading bug to the aircraft heading.
2. Press the FD button on the GMC 605 to engage the flight director.
3. Verify ROL and PIT are displayed on the GMC 605, GI 285, and PFD.
4. Press the HDG button on the GMC 605 to select heading mode.
5. Verify HDG and PIT are displayed on the GMC 605, and that HDG and PIT are
illuminated in green and ROL is extinguished on the GI 285 and the PFD.
6. Adjust the heading bug to the left.
7. Verify that the flight director command bars indicate a left turn command.
8. Rotate the NOSE UP/DN thumbwheel UP four times.
9. Verify that the flight director command bars indicate a pitch up command.
10. Press the LVL button on the GMC 605.
11. Verify that LVL and LVL are displayed on the GMC 605.
12. Verify that LVL and LVL are displayed in green and HDG and PIT are extinguished on
the GI 285 and the PFD.
13. Verify that the flight director command bars show level attitude.
14. Set the heading bug to the aircraft heading.
15. Press the AP button on the GMC 605 to engage the autopilot.
16. Verify ROL and PIT are displayed on the GMC 605, GI 285, and PFD.
17. Press the HDG button on the GMC 605 to select heading mode.
18. Verify HDG and PIT are displayed on the GMC 605, and that HDG and PIT are
illuminated in green and ROL is extinguished on the GI 285 and the PFD.
19. Adjust the heading bug to the left.
20. Verify that the autopilot drives the flight controls into a left turn.
21. Rotate the NOSE UP/DN thumbwheel UP four times.
22. Verify that the autopilot drives the flight controls to a nose up direction.
23. Press the LVL button on the GMC 605.
24. Verify that LVL and LVL are displayed on the GMC 605.
25. Verify that LVL and LVL are displayed in green and HDG and PIT are extinguished on
the GI 285 and the PFD.
26. Verify that the autopilot stops driving the flight controls.
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Appendix A.
Installation Specific Information
A copy of this appendix must be used to record information for a specific installation of the GFC
600 AFCS system. The completed copy must be kept with the aircraft permanent records. This
appendix includes the following information:
•
General installation information
•
Interfaced equipment
•
GFC 600 AFCS configuration log
•
GFC 600 AFCS wiring diagrams
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A.1.
General Installation Information
Aircraft
Aircraft Make and Model______________________________________________________
Serial Number______________________________________________________________
Registration Number_________________________________________________________
GMC 605 AFCS Mode Controller
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
Software Loader Card Part Number (shown on splash screen) ________________________
Air Data Module (ADM) (if installed)
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
GI 285 AFCS Mode Annunciator (if installed)
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
GSA 87 Pitch Servo
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
GSA 87 Roll Servo
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
GSA 87 Pitch Trim Servo (if installed)
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
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GSA 87 Yaw Damper Servo (if installed)
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
GTA 82 Trim Adapter (if installed)
Part Number_______________________________________________________________
Serial Number______________________________________________________________
Mod Level_________________________________________________________________
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A.2.
Interfaced Equipment
NOTE: Completion of this section and its retention with the aircraft records is required.
A.2.1. Garmin Equipment
Use Table A-1 to document GFC 600 AFCS system interfaces with other Garmin equipment
installed in the aircraft. GFC 600 AFCS system interfaces to all equipment listed in Table A-1
are covered by this STC. Refer to installation specific interconnect diagrams retained with the
aircraft permanent records for detailed equipment interface information. In the notes section,
record the external LRU software version and configuration settings.
Equipment
Table A-1 – Garmin Equipment
Interfaced
Notes/Software Version/Configuration Specifics
GDU 620
 Yes
 No
GDU7XX/GDU1060
 Yes
 No
GTN 6XX
 Yes
 No
GTN 7XX
 Yes
 No
GNS 400/500 Series
 Yes
 No
GNS 480 (CNX 80)
 Yes
 No
GPS 155XL / GNC 300XL
 Yes
 No
GNC 255
 Yes
 No
GTX 3X5 (R) w/ GPS
 Yes
 No
GDC 72( )
 Yes
 No
GDC 74( )
 Yes
 No
GSU 75( )
 Yes
 No
SL 30
 Yes
 No
GMA 35 / 350
 Yes
 No
G5 Electronic Flight Instrument  Yes
 No
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A.2.2. Other Equipment
Use Table A-2 to document GFC 600 AFCS system interfaces with other equipment installed in
the aircraft, but not listed in Table A-1. Refer to the GFC 600 AFCS Part 23 STC Installation
Manual, 190-01937-00, to determine whether interfaces between the GFC 600 AFCS and the
equipment listed in Table A-2 are covered by this STC. In the notes section, record the external
LRU software version and configuration settings.
Equipment
Model
Table A-2 – Other Equipment
Interface Format Covered by this
STC?
GFC 600 AFCS Part 23 AML STC Maintenance Manual
190-01938-00
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
 Yes
 No
Notes/Configuration
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A.3.
Configuration Log
Configuration Item
Setting
SYS > INSTALL Page 1/3
PTRM
 No
 Yes
YAW DAMPER
 No
 Yes
GI 285
 No
 Yes
HSI/DG
 No
 52D54
 GDU  KI525
 G502A
FLT DIR
 No
 GDU
GPS ROLSTR
 No
 Yes
GPS DEV
 Angulr
 Linear
VNAV
 No
 Yes
COL SNSR
 None
 LVDT
CBN PRSSR
 None
 ADM
 Cent NSD
SYS > INSTALL Page 2/3
 Aspen
 G5
SYS > INSTALL Page 3/3
 Pot
GMC DSP > BACKLIGHT page
SOURCE
 PHOTOCELL  14VDC  28VDC  5VDC  5VAC
TRANSITION
GMC DSP > LIGHTBUS DISP page 1/2
X1:
Y1:
X2:
Y2:
GMC DSP > LIGHTBUS DISP page 2/2
X3:
Y3:
X4:
Y4:
GMC DSP > LIGHTBUS KEYS page 1/2
X1:
Y1:
X2:
Y2:
GMC DSP > LIGHTBUS KEYS page 2/2
X3:
Y3:
X4:
Y4:
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Configuration Item
Setting
GMC DSP > PHOTOCEL DISP page 1/2
X1:
Y1:
X2:
Y2:
GMC DSP > PHOTOCEL DISP page 2/2
X3:
Y3:
X4:
Y4:
GMC DSP > PHOTOCEL KEYS page 1/2
X1:
Y1:
X2:
Y2:
GMC DSP > PHOTOCEL KEYS page 2/2
X3:
Y3:
X4:
Y4:
GMC DSP > CONTRAST page
OFFSET
RMT DSP > BACKLGHT page
SOURCE
 PHOTOCELL  14VDC  28VDC  5VDC  5VAC
TRANSITION
RMT DSP > LIGHTBUS page 1/2
X1:
Y1:
X2:
Y2:
RMT DSP > LIGHTBUS page 2/2
X3:
Y3:
X4:
Y4:
GFC 600 AFCS Part 23 AML STC Maintenance Manual
190-01938-00
Page A-7
Revision 6
Configuration Item
Setting
RMT DSP > PHOTOCEL page 1/2
X1:
Y1:
X2:
Y2:
RMT DSP > PHOTOCEL page 2/2
X3:
Y3:
X4:
Y4:
TEST > AUDIO page
Volume
GFC 600 AFCS Part 23 AML STC Maintenance Manual
190-01938-00
Page A-8
Revision 6
A.4.
Equipment Locations and Wiring
For the locations of installed equipment, refer to the appropriate Install Manual Addendum (19001937-XX).
Record equipment locations and sketch the approximate location of wire routing in or as
applicable.
Figure A-1 – Equipment Location and Wire Routing – Single Engine Airplane
GFC 600 AFCS Part 23 AML STC Maintenance Manual
190-01938-00
Page A-9
Revision 6
Figure A-2 – Equipment Location and Wire Routing – Twin Engine Airplane
GFC 600 AFCS Part 23 AML STC Maintenance Manual
190-01938-00
Page A-10
Revision 6
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