COBHAM LGA-5005 HLD User manual

LGA-5005 HLD and
Installation manual
Enhanced Low Gain Antenna (HELGA)

Cobham Public
LGA-5005 (HELGA)
Installation manual
Document number: 98-152675-A
Release date: 15 December 2020

ii 98-152675-A
Cobham Public
Disclaimer
Information in this document is subject to change without notice.
The information, drawings and wiring diagrams contained in this manual are intended as a reference for
engineering planning only. The drawings and wiring diagrams contained herein do not represent any
specific Supplemental Type Certificate (STC). It is the installer's responsibility to produce installation
drawings specific to the aircraft. This manual and the drawings and wiring diagrams contained herein may
not be used as a substitute for an STC package.
The newest versions of Cobham SATCOM user and installation manuals as well as outline drawings can be
downloaded from www.cobham.com/satcom, Cobham SYNC Partner Portal. Some material and
features are for partners only and can only be accessed after login with a password.
Thrane & Thrane A/S is not responsible for the content or accuracy of any translations or reproductions,
in whole or in part, of this manual from any other source. In the event of any discrepancies, the English
version shall be the governing text.
Thrane & Thrane A/S is trading as Cobham SATCOM.
Controlled documentation
Notwithstanding the terms of the above disclaimer, Cobham SATCOM undertakes in the case of
controlled documentation to supply the customer with all updates or amendments to this document and
furthermore undertakes to notify the customer in advance of material changes to the information
contained herein.
Manufacturer address
Thrane & Thrane A/S, Lundtoftegårdsvej 93D, DK-2800, Kgs. Lyngby, Denmark
Copyright
© 2020 Thrane & Thrane A/S. All rights reserved. Printed in Denmark.
Trademark Acknowledgements
•Inmarsat is a registered trademark of the International Maritime Satellite Organization (IMSO) and is
licensed by IMSO to Inmarsat Limited and Inmarsat Ventures plc.
• Inmarsat’s product names are either trademarks or registered trademarks of Inmarsat.
• Other product and company names mentioned in this manual may be trademarks or trade names of
their respective owners.
Company web site:
www.cobham.com/satcom

98-152675-A iii
Cobham Public
Disposal
Old electrical and electronic equipment marked with this symbol can contain substances
hazardous to human beings and the environment. Never dispose these items together with
unsorted municipal waste (household waste). In order to protect the environment and
ensure the correct recycling of old equipment as well as the re-utilization of individual
components, use either public collection or private collection by the local distributor of old
electrical and electronic equipment marked with this symbol.
Contact the local distributor for information about what type of return system to use.
Record of revisions
Rev. Description Release Date Initials
A Original version 15 December 2020 UFO

iv 98-152675-A
Cobham Public
Safety summary
The following general safety precautions must be observed during all phases of operation,
service and repair of this equipment. Failure to comply with these precautions or with specific
warnings in this manual may violate the safety standards of design, manufacture and intended
use of the equipment.
Radiation warning
During transmission the LGA-5005 can radiate microwave power in any direction not screened
by the aircraft fuselage. High levels of radio frequency radiation are considered harmful to
health. Although all countries have not agreed upon a single value, the American National
Standards Institute (ANSI/IEEE C95.1-1999) recommends that any person in a controlled
environment should not be exposed to radiation stronger than 5 mW/cm2 at the frequencies
used in this system.
System cable installation
Take care when planning the routing of cables to and from the LGA-5005. The installation of
these cables must not interfere with existing aircraft systems or make future interference
possible. Secure and insulate all cables correctly. Adhere to the minimum bend radius
specifications.
Hardware installation
The installation of the LGA-5005 must not compromise the safety or integrity of the aircraft
structure. Take care to prevent any changes to vital aircraft components or structures when
installing the antenna.
WARNING! Keep a safety distance of minimum 60 cm (2 ft) to the antenna
when the system is transmitting,

98-152675-A v
Cobham Public
Table of Contents
Chapter 1 About This Manual
1.1 Purpose .....................................................................................................................................1-1
1.2 Manual overview ...............................................................................................................1-1
1.3 Precautions ............................................................................................................................1-2
Chapter 2 Introduction
2.1 Scope .........................................................................................................................................2-1
2.2 System overview ...............................................................................................................2-2
2.3 Interface of the LGA-5005 ........................................................................................2-3
Chapter 3 Installation
3.1 General information and overview .....................................................................3-1
3.2 Storage and transportation ......................................................................................3-1
3.3 Unpacking & initial inspection ...............................................................................3-2
3.4 Prerequisites .........................................................................................................................3-3
3.4.1 Antenna location and mounting considerations .................................................3-3
3.4.2 Structural modifications and sealing .........................................................................3-3
3.4.3 Grounding ...............................................................................................................................3-5
3.4.4 Alignment and installation limitations ......................................................................3-5
3.5 Installation of the antenna ......................................................................................3-8
3.5.1 Installation verification .................................................................................................3-10
3.6 Removal of the antenna ...........................................................................................3-10
Chapter 4 Maintenance
4.1 General maintenance and repair ..........................................................................4-1
4.1.1 Technical support ...............................................................................................................4-1
4.1.2 Repair and Servicing ..........................................................................................................4-1
4.1.3 Maintenance intervals ......................................................................................................4-1
4.2 Events generated by the LGA-5005 ...................................................................4-2
4.3 Returning units for repair ...........................................................................................4-3
4.3.1 Return Material Authorization (RMA) ........................................................................4-3
Chapter 5 Special tools, fixtures and equipment
Chapter 6 Illustrated parts list
Appendix A Equipment specifications
A.1 LGA-5005 specifications .............................................................................................A-1

Table of Contents
vi 98-152675-A
Cobham Public
A.2 DO-160 specifications ...................................................................................................A-2
A.2.1 Qualification Forms ............................................................................................................A-2
A.3 Certification ..........................................................................................................................A-5
A.3.1 Certifying agency ................................................................................................................A-5
A.3.2 List of (E)TSOs and deviations ......................................................................................A-5
Appendix B References
B.1 References .............................................................................................................................B-1
Glossary ..............................................................................................................................................................Glossary-1
Index ....................................................................................................................................................................Index-1

98-152675-A vii
Cobham Public
List of figures
Figure 2-1: LGA-5005..............................................................................................................................................................2-1
Figure 2-2: AVIATOR 200 S with LGA-5005 ................................................................................................................2-3
Figure 3-1: Mounting hole sealing kit..............................................................................................................................3-2
Figure 3-2: Areas where NO sealant is to be applied................................................................................................3-4
Figure 3-3: Breathing/drainage slots, both sides ........................................................................................................3-4
Figure 3-4: Fore/aft of the antenna..................................................................................................................................3-5
Figure 3-5: Base of the antenna.........................................................................................................................................3-8
Figure 3-6: Sealant application to the bolt access holes of the antenna radome......................................3-9
Figure 6-1: LGA-5005 – HELGA ..........................................................................................................................................6-1

98-152675-A viii
Cobham Public
List of tables
Table 2-1: Equipment covered .......................................................................................................................................... 2-1
Table 2-2: Summary of system equipment.................................................................................................................2-2
Table 2-3: Coaxial cable characteristics........................................................................................................................2-4
Table 4-1: Inspection tasks for LGA-5005...................................................................................................................4-2
Table 5-1: Tools, fixtures and equipment required for the LGA-5005 installation..................................5-1
Table 5-2: List of supplies.....................................................................................................................................................5-1
Table 6-1: Legend for figure items ..................................................................................................................................6-2
Table A-1: Equipment specifications for LGA-5005................................................................................................A-1
Table A-2: Qualification Forms..........................................................................................................................................A-2
Table A-3: Common environmental conditions and tests (DO160G) for LGA-5005..............................A-2

98-152675-A 1-1
Chapter 1
1111
Cobham Public
About This Manual 1
1.1 Purpose
This installation manual provides the general instruction for the installation of the LGA-
5005 on aircraft.
It is important that you observe all safety requirements listed in the beginning of this
manual, and install the system according to the guidelines in this manual.
1.2 Manual overview
The manual is structured in chapters and appendices:
•Introduction
This chapter contains a short presentation of the LGA-5005, interface and outline
drawing.
•Installation
This chapter contains information about storage, transportation, unpacking and
instructions how to install and remove the antenna.
•Maintenance
Maintenance interval and actions. Repair and servicing.
•Special tools, fixtures and equipment
•Appendices
The appendices contain equipment specifications and a list of references.
•Glossary
Abbreviations and acronyms
•Index
Important
The information, drawings and wiring diagrams contained in this manual are
intended as a reference for engineering planning only. The drawings and
wiring diagrams contained herein do not represent any specific certified
installation design. It is the installer's responsibility to produce installation
drawings specific to the aircraft. This manual and the drawings and wiring
diagrams contained herein may not be used as a substitute for a certified
design package.

Precautions
1-2 Chapter 1: About This Manual 98-152675-A
Cobham Public
1.3 Precautions
Warnings, Cautions and Notes
Text marked with “Warning”, “Caution”, “Note” or “Important” show the following type of
data:
•Warning: A Warning is an operation or maintenance procedure that, if not obeyed, can
cause injury or death, or jeopardize the flight safety on the aircraft.
•Caution: A Caution is an operation or maintenance procedure that, if not obeyed, can
cause damage to the equipment.
•Note: A Note gives information to help the reader.
•Important: A text marked Important gives information that is important to the user,
e.g. to make the system work properly. This text does not concern damage on
equipment, flight safety nor personal safety.
General precautions
All personnel who operate equipment or do maintenance as specified in this manual must
know and follow the safety precautions.
The warnings and cautions that follow apply to all parts of this manual.
WARNING! Before using any material, refer to the manufacturers’ material
safety data sheets for safety information. Some materials can be dangerous.
CAUTION! Do not use materials that are not equivalent to materials
specified by Cobham SATCOM. Materials that are not equivalent can cause
damage to the equipment.
CAUTION! The system contains items that are sensitive to electrostatic
discharge. Use approved industry precautions to keep the risk of damage to a
minimum when you touch, remove or insert parts or assemblies.

98-152675-A 2-1
Chapter 2
2222
Cobham Public
Introduction 2
2.1 Scope
This installation manual provides the general installation instructions and mounting
considerations for the LGA-5005, part number: 405005.
The Design Assurance Level of the LGA-5005 for software and hardware is DAL D.
The installer must derive specific installation details for each different aircraft type, using
this manual as a guideline, while adhering to standard aircraft practices, refer to [1], or its
equivalent.
The following figure shows the LGA-5005.
CAUTION! The material in this manual is subject to change. Before you
start with the installation you must verify that the complete and up-to-date
publication is used.
Figure 2-1: LGA-5005
Type
Number Equipment Name Abbreviated Name
Certified
Part Numbera
a. Final PNR suffix vvccc: vv = customer specific, ccc = minor variants
OEM PNR
[for Cobham internal use only]
LGA-5005 HLD/Enhanced
Low Gain Antenna
HELGA 405005-vvccc 677-A0213
Table 2-1: Equipment covered

System overview
2-2 Chapter 2: Introduction 98-152675-A
Cobham Public
2.2 System overview
The purpose of the LGA-5005 is to provide an L-band radio link between the Inmarsat
SwiftBroadband Class 4 SATCOM system AVIATOR 200S and an Inmarsat I4 satellite. For
SwiftBroadband services, the LGA-5005 is part of a single channel aeronautical SATCOM
system comprising the following subsystems (as defined in ARINC 781-6, Attachment 7,
Configuration 3 [4]), interconnected as shown in Figure 2-2:.
• LGA-5005 HLD/Enhanced Low Gain Antenna (HELGA)
• SDU-5045 Compact Satellite Data Unit (CSDU)
• SCM-5055 CSDU Configuration Module (SCM)
Type
Number Equipment Name Abbreviated Name
Certified
Part Numbera
a. Final PNR suffix vvccc: vv = customer specific, ccc = minor variants
OEM PNR
[for Cobham internal use only]
LGA-5005 HLD/Enhanced
Low Gain Antenna
HELGA 405005-vvccc 677-A0213
SCM-5055 Compact SDU
Configuration
Module
SCM 405055-vvccc 677-A0217
SDU-5045 Compact Satellite
Data Unit
CSDU 405045-vvccc –
Table 2-2: Summary of system equipment

Interface of the LGA-5005
98-152675-A Chapter 2: Introduction 2-3
2222
Cobham Public
The following block diagram shows the AVIATOR 200S system with LGA-5005:
The LGA-5005 is intended to comply with DO-262B, Appendix E, as part of an AES4 system.
LGA-5005 may only be installed with an AVIATOR-S CSDU [SDU-5045, part number
405045-vvccc] and SCM [SCM-5055, part number 405055-vvccc]. Together, these three
items form a complete AES4 system, as defined in DO-262B, Appendix E.
The LGA-5005 is powered by the CSDU (SDU-5045) of the AVIATOR 200S system.
2.3 Interface of the LGA-5005
The LGA-5005 has a single TNC female bulkhead connector to interface to the CSDU. This
interface carries the following signals, separated in the frequency domain:
• DC supply from the CSDU to power the LGA-5005
• RF Tx signal to be amplified and transmitted from the antenna.
• RF Rx signal received by the antenna and amplified by the LNA.
• Control link modem signal from the CSDU to the LGA-5005.
• Status link modem signal from LGA-5005 to the CSDU.
The interconnection cable design will be specific to the requirements of the aircraft type.
The interconnection cable between the antenna and the CSDU may be supplied as part of
Figure 2-2: AVIATOR 200 S with LGA-5005

Interface of the LGA-5005
2-4 Chapter 2: Introduction 98-152675-A
Cobham Public
the antenna or separately. The cable must meet the requirements set out in the following
table.
The definition of the electrical signals carried on the cable interface between LGA-5005 and
the CSDU is specific to the Cobham AVIATOR-S system. LGA-5005 shall never be
interfaced to any avionics other than an AVIATOR-S CSDU [part number 405045-vvccc].
Characteristic Value
Interface impedance 50 Ohm.
Maximum allowed RF cable loss between CSDU and LGA-5005 18 dB at 1.6 GHz.
Maximum allowed cable DC resistance 0.6 Ohm.
Table 2-3: Coaxial cable characteristics

98-152675-A 3-1
Chapter 3
3333
Cobham Public
Installation 3
3.1 General information and overview
This chapter contains considerations and recommendations for installation of the LGA-
5005. Wiring and physical mounting must satisfy all applicable regulations.
This chapter has the following sections:
•Storage and transportation
•Unpacking & initial inspection
•Prerequisites
•Installation of the antenna
•Removal of the antenna
Field-loadable Software (FLS) part number: Refer to [6], 98-145168; AVIATOR 200S
Installation Manual (Cockpit)
The Design Assurance Level of the LGA-5005 for software and hardware is DAL D.
3.2 Storage and transportation
Store the box in a dry area (< 50% RH) where the temperature is within the range of -55 °C
to + 85 °C (- 67 °F and + 185 °F).
Important
The information, drawings and wiring diagrams contained in this manual are
intended as a reference for engineering planning only. The drawings and
wiring diagrams contained herein do not represent any specific certified
installation design. It is the installer's responsibility to produce installation
drawings specific to the aircraft. This manual and the drawings and wiring
diagrams contained herein may not be used as a substitute for a certified
design package.
Note
To ensure optimal performance of the LGA-5005, strict adherence to the
installation considerations found in this section must be maintained.

Unpacking & initial inspection
3-2 Chapter 3: Installation 98-152675-A
Cobham Public
3.3 Unpacking & initial inspection
Inspect the shipping container immediately upon receipt for evidence of damage during
transport. If the shipping container is severely damaged or water stained, request that the
carrier's agent be present when opening the carton.
Unpack and check that the following items are present:
•LGA-5005
• Mounting hole sealing kit
After unpacking the LGA-5005, inspect it thoroughly for hidden damage and loose
components or fittings. If the contents are incomplete or there is mechanical damage or
defect, notify your supplier.
Verify the following during unpacking of the unit:
• The connector has a protective cap fitted.
Retain the protective connector cap, packing material and containers for future storage
and/or shipping use.
Note
The sealing kit contains 6 sealing caps and air displacers (two are spares)
Figure 3-1: Mounting hole sealing kit

Prerequisites
98-152675-A Chapter 3: Installation 3-3
3333
Cobham Public
3.4 Prerequisites
Before you start to install the antenna, read the following sections carefully:
•Antenna location and mounting considerations
•Structural modifications and sealing
•Grounding
•Alignment and installation limitations
Refer to [2] for an outline drawing of the LGA-5005.
3.4.1 Antenna location and mounting considerations
This section provides information on the mounting of the LGA-5005 hardware and the
installation of the antenna.
Make sure that the installation is in accordance with the following mounting considerations:
• Mount the LGA-5005 antenna on top of the fuselage.
• In some instances a mounting plate may be used to install the LGA-5005 onto the
aircraft fuselage. This document can also be followed when the LGA-5005 is installed
onto a mounting plate. Contact the antenna manufacturer for the relevant mounting
plate installation instructions in order to install a mounting plate onto the aircraft
fuselage.
• The antenna base is profiled with a radius of 3.25 m [127.95"].
If the fuselage radius is less than 1.8 m, contact the antenna manufacturer for a suitable
solution (adaptor plate).
• Mount the LGA-5005 antenna in a position with a clear view of the sky.
• Make sure that the mounting location is interference free, refer to Co-location with
other antennas on page 3-6.
For a detailed step-by-step installation procedure see Installation of the antenna on
page 3-8.
3.4.2 Structural modifications and sealing
Structural loads
The effect of the installed antenna on the fuselage is airframe specific. A structural analysis
must be performed to determine what structural modifications to the airframe are required
before installing the antenna. This is the responsibility of the installation designer.
Sealing of the antenna
Sealing of the gap between antenna and fuselage skin is an aspect that is determined by
customer preference. Cobham does not require the underside of the antenna to be sealed
since there is no unprotected metal prone to corrosion.
Many years’ experience on a similar installation concept has proven this. If, however, the
customer has a requirement for fuselage skin protection, he should consider the use of an
in-situ injectable sealant or a gasket to afford the necessary protection against corrosion.
Use of a gasket is not straightforward and will require the installer to determine if adequate
compression can be supplied by the 4 mounting bolts to still attain sealing around the

Prerequisites
3-4 Chapter 3: Installation 98-152675-A
Cobham Public
connector/skin penetration area. The gasket may have to be reduced in size to achieve this
and it will be different for different radii of aircraft fuselages.
If an injectable sealant is considered:
1. Apply sealant to the whole undersurface, EXCEPT the yellow areas, the O-ring and the
area inside the O-ring as indicated in Figure 3-2
2. Take care that NO SEALING is applied in the breathing/drainage slot areas indicated in
Figure 3-3. The breathing and drainage slots are also the air paths to allow breathing and
drainage of liquids penetrating the slots due to cleaning or de-icing of the aircraft.
Important
The sealing compound should have a low enough viscosity to be squeezed
out readily during fastening of the attachment bolts to ensure that the
antenna is seated as close to the fuselage skin as possible, i.e. the bonding
areas (feet) should be in contact with the fuselage skin.
Note
Note the requirements for provisions for grounding and bonding in section
3.4.3 (GB).
Figure 3-2: Areas where NO sealant is to be applied
Figure 3-3: Breathing/drainage slots, both sides
Mounting foot
GB
Mounting foot
GB O-ring sealing area
GB

Prerequisites
98-152675-A Chapter 3: Installation 3-5
3333
Cobham Public
3.4.3 Grounding
It is the responsibility of the installer to ensure that the grounding between the LGA-5005
and the fuselage is in accordance with the airframe manufacturer’s requirements. The
primary method of grounding the LGA-5005 is through the mounting bolts. Grounding may
also be achieved through the mounting feet which are not painted, but chemically
converted to allow for grounding to unpainted surfaces (see Figure 3-2).
In the case where the LGA-5005 is installed with a mounting plate, the four LGA-5005 to
mounting plate bolts provide the primary grounding between the LGA-5005 and the plate.
As mentioned above, the mounting feet provide additional grounding to the matching
unpainted areas on the mounting plate.
3.4.4 Alignment and installation limitations
Consider the following factors that influence the final position of the antenna:
•Alignment and installation offset angles
•Lightning strike
•RF blockage
•Co-location with other antennas
•Fuselage Structure
•Engines and APU inlets
Alignment and installation offset angles
Install the LGA-5005 with its long axis facing fore/aft, with the ventilation/breathing holes
located in the aft position.
You may install the LGA-5005 slightly off the aircraft centre-line (roll offset), and/or with its
nose slightly up or down (pitch offset). In this manual these are called installation offset
angles.
The installation offset angles of the LGA-5005 are compensated for by the CSDU, in which
case you must measure the yaw-, roll- and pitch-offsets. It is recommended that the
CAUTION! The Installer must take corrosion effects into account
especially when dissimilar materials are involved.
Figure 3-4: Fore/aft of the antenna
Fore Aft