draft RRCS Requirements Specification_09 2025.pdf

FAA-E-3037A, September 2025

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

REMOTE RADIO CONTROL SYSTEM (RRCS)

REQUIREMENTS SPECIFICATION

FAA Visual Guidance Lighting Systems Team

AJM-3220

FAA-E-3037A

i February 2022

TABLE OF CONTENTS

1 INTRODUCTION

1.1 Scope

1.2 Overview

2 APPLICABLE DOCUMENTS

2.1 General

2.2 Government Documents

2.2.1 FAA specifications, standards, handbooks, and drawings

2.2.2 Federal specifications, handbooks, and drawings

2.2.3 Military specifications and handbooks

2.2.4 Non-government publications

3 REQUIREMENTS

3.1 System Description

3.1.1 Control Display Unit (CDU) Description

3.1.2 Transmitter Control Unit (TCU) Description

3.1.3 Remote VGLS Interface Unit (RVIU) Description

3.2 System Backward Compatibility Requirements

3.2.1 Tower Equipment Backward Compatibility

3.2.2 Field Equipment Backward Compatibility

3.3 RRCS Unit Requirements

3.3.1 Control Display Unit (CDU)

3.3.2 Transmitter Control Unit (TCU)

3.3.3 Remote VGLS Interface Unit (RVIU)

3.3.4 Maintenance Terminal (MT)

3.3.5 Ancillary Equipment

3.4 User Interface (UI) Requirements

3.4.1 Main Screen

3.4.2 Runway Approach Screens

3.4.3 A/G Mode

3.4.4 Auxiliary Screens

3.5 Human Factor Requirements

3.5.1 Luminance and Contrast

3.5.2 Glare Control

3.5.3 Visual Control-Indicator Relationship

3.5.4 Push Buttons

3.6 System Requirements

3.6.1 Service Entrance Clearance

3.6.2 Lightning/Transient Protection

3.6.3 Electromagnetic Interference (EMI)

3.6.4 Equipment Recovery

3.6.5 Electrical Requirements

3.6.6 Mechanical Requirements

3.6.7 LRU Interchangeability

3.6.8 Test points

3.6.9 Derating of Electronic Parts

FAA-E-XXXX

ii September 2025

3.6.10 Enclosures

3.6.11 Enclosure Finishes

3.6.12 Door Gasket

3.6.13 Cabinet Door

3.6.14 Hinged Panel Cable

3.6.15 Cabinet Door Handle

3.6.16 Earth Grounding

3.6.17 Nameplates

3.6.18 Assembly and Marking

3.6.19 Thermal Design

3.7 Personnel Safety and Health

3.7.1 Terminal Block

3.7.2 Electrical Safety

3.7.3 Ground Potential

3.7.4 Hinged or Side Mounted Panels and Doors

3.7.5 Shielding

3.7.6 High Voltage Protection

3.7.7 Discharging Devices

3.7.8 Mechanical Hazards

3.7.9 Mechanical Interconnection

3.7.10 Markings, Signs, Tags and Symbols

3.8 Parts, Materials, and Processes

3.8.1 Parts

3.8.2 Materials

3.8.3 Processes

3.9 Environmental Requirements

3.9.1 Outdoor Equipment Operating Temperature and Humidity

3.9.2 Vibration

3.9.3 Sand and Dust

3.9.4 Salt Fog

3.9.5 Combined Rain and Wind

3.9.6 Non-Operating Environmental Requirements

3.10 Reliability

3.11 Maintainability

3.11.1 Software/Firmware Updates

4 VERIFICATION

4.1 Methods of Verification

4.2 Test Allocation

4.2.1 Development Test (DT)

4.2.2 Production Acceptance Tests (PAT)

4.2.3 Type Tests

4.2.4 Operational Test (OT)

4.3 Test Procedures

4.3.1 Visual Inspection

4.3.2 Backward Compatibility Test

4.3.3 Power Tests

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4.3.4 Electromagnetic Interference Test

4.3.5 Transient Suppression Test

4.3.6 Environmental Tests

4.3.7 Functional Tests

4.3.8 Reliability

4.3.9 Maintainability Demonstration

5 ABBREVIATIONS AND ACRONYMS

VERIFICATION REQUIREMENT TRACEABILITY MATRIX (VRTM)

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Table of Figures

Figure 3-1. Example CDU (Front/Back Views) Figure 3-2. Legacy RRCS Equipment (Tower and Field) Figure 3-3. Backward Compatibility Between New Tower Equipment and Legacy Field

Equipment Figure 3-4. Backward Compatibility Between New Field Equipment and Legacy Tower

Equipment Figure 3-5. Serial Data Stream Format Figure 3-6. Function Command Code Format Figure 3-7. CDU Main Screen (a-b) Figure 3-8. Runway Approach Screen Figure 3-9. Runway Approach Screen – OTS Figure 3-10. Example MALSR ON Control Functionality Figure 3-11. Example MALSR OFF Control Functionality Figure 3-12. Example MALS OFF Control Functionality Figure 3-13. PAPI/VASI Control Functionality Figure 3-14. A/G Mode Selection (a-b) Figure 3-15. RRCS OTS Screen Figure 3-16. Communication Failure Screen Figure 3-17. Screen Cleaning Mode (a-b) Figure 3-18. Standard FAA Nameplate Figure 3-19. Personnel Safety Sign Layout

List of Tables

Table 3-1. RVIU Interface Capabilities Table 3-2. RVIU Remote Control Logic Table 3-3. VSWR Requirements Table 3-4. TCU and RVIU Antenna Characteristics Table 3-5. Antenna Performance Characteristics Table 3-6. Sand and Dust Particles Table 3-7. Equipment Reliability Requirements Table 3-8. Maintainability Requirements Table 4-1. First Article Development Test Table 4-2. Production Acceptance Tests Table 4-3. Type Tests Table 4-4. Vibration Test Data Table 4-5. RVIU Orientation and Test Duration Table 4-6. Sand and Dust Particles Table 4-7. Combined Rain and Wind Table 4-8. Test Cycles

1 September 2025

1 INTRODUCTION

1.1 Scope

This Federal Aviation Administration (FAA) specification establishes the performance and verification requirements for the Remote Radio Control System (RRCS) equipment to upgrade current FA-10266 equipment.

1.2 Overview

The RRCS is a service system consisting of hardware and software that is used by Air Traffic

Controllers (ATC) to operate an airport’s suitably equipped Visual Guidance Lighting Systems

(VGLS). The RRCS enables ATC to turn VGLSs ON or OFF; change intensity levels on select equipment; and enable or disable control of VGLS equipment by airborne users.

2 APPLICABLE DOCUMENTS

2.1 General

The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they shall meet all specified requirements of documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed.

2.2 Government Documents

The following specifications and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues and revisions of these documents are those cited in the solicitation or contract.

2.2.1 FAA specifications, standards, handbooks, and drawings

FAA-G-2100 Electronic Equipment, General Requirements

FAA-STD-019 Lightning and Surge Protection, Grounding, Bonding, and

Shielding Requirements for Facilities and Electronic

Equipment

TI 6850.83 Technical Instruction Book for the Remote Radio Control

System (RRCS)

2.2.2 Federal specifications, handbooks, and drawings

DOT/FAA/CT-961 Human Factors Design Guide (HFDG) For Acquisition Of

Commercial Off-The-Shelf Subsystems, Non-

Developmental Items (NDI), And Developmental Systems

JO 6850.5 Maintenance Handbook

2 September 2025

SAE AMS-STD-595 Federal Standard: Colors Used In Government Procurement

CFR Title 29, Part 1910 Occupational Safety and Health Act (OSHA)

CFR Title 29, Part 1926 Occupational Safety and Health Act (OSHA)

FEMA Publication 302 National Earthquake Hazards Reduction Program

QQ-A-200/9 Aluminum Alloy 6063, Bar, Rod, Shapes, Tube And Wire, Extruded

QQ-A-225 Aluminum And Aluminum Alloy Bar, Rod, Wire, Or

Special Shapes; Rolled, Drawn, Or Cold Finished

QQ-A-250 Aluminum And Aluminum Alloy Plate And Sheet

QQ-A-591 Aluminum Alloy Die Castings

QQ-A-601 Aluminum Alloy Sand Castings

2.2.3 Military specifications and handbooks

MIL-T-152B Treatment, Moisture and Fungus Resistant, of

Communications, Electronic and Associated Electrical

Equipment

MIL-STD-889 Dissimilar Metals

MIL-HDBK-1516 Unified Code for Coatings and Finishes for DOD Materiel

MIL-STD-810H Environmental Considerations and Laboratory Tests

MIL-STD-461 Requirements for the Control of Electromagnetic

Interference Characteristics of Subsystems and Equipment

2.2.4 Non-government publications

2.2.4.1 Institute of Electrical and Electronics Engineers (IEEE)

IEEE STD 141 IEEE Recommended Practice for Electric Power

Distribution for Industrial Plants

ANSI/IEEE-200 IEEE Reference Designations for Electrical and Electronics

Parts and Equipment

ANSI/IEEE C95.1-1991 IEEE Standard for Safety Levels with Respect to Human

Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz

2.2.4.2 International Electrotechnical Commission (IEC)

IEC 61000-3-2:2018 Electromagnetic Compatibility (EMC) - Part 3-2: Limits -

Limits for harmonic current emissions (equipment input current ≤16 A per phase)

2.2.4.3 National Electrical Code (NEC)

National Electrical Code NFPA Code 70

2.2.4.4 Institute of Printed Circuits (IPC)

IPC-A-600 Acceptability of Printed Boards

3 September 2025

IPC-CC-830 Qualification and Performance of Electrical Insulating

Compound for Printed Wiring Assemblies

IPC-A-610 Acceptability of Electronic Assemblies

J-STD-001 Requirements for Soldered Electrical and Electronic

Assemblies

2.2.4.5 UL Standards

UL 489 Molded-Case Circuit Breakers, Molded-Case Switches, and

Circuit-Breaker Enclosures

NEMA National Electrical Manufacturer Association

4 September 2025

3 REQUIREMENTS

This specification describes architecture considerations, major functions, and design requirements for the RRCS system. The RRCS shall meet the requirements specified herein while operating over the full-range of the operating environment defined herein.

3.1 System Description

The RRCS provides the Air Traffic Control (ATC) and pilots a means to control the following

Visual Guidance Lighting System (VGLS) equipment installed at an airport:

• Medium Intensity Approach Lighting Systems (MALS)

• Medium Intensity Approach Lighting Systems with Runway Alignment Indicator Lights

(MALSR)

• Precision Approach Path Indicator (PAPI)

• Omnidirectional Approach Lighting System (ODALS)

• Runway End Identifier Lights (REIL)

• Visual Approach Slope Indicator (VASI)

The RRCS is composed of three (3) major units that include one (1) Control Display Unit (CDU), one (1) Transmitter Control Unit (TCU), and one (1) Remote VGLS Interface Unit (RVIU). The

CDU is located in the Airport Traffic Control Tower (ATCT) cab and provides ATC personnel the means to control the VGLS equipment installed in the field. The TCU in the equipment room receives all commands from the CDU and broadcasts the commands to the RVIUs in the field via radio link. The RVIUs use the commands received from the TCU to control the VGLSs installed in the field. In addition, the RVIU(s) has an interface capable of connecting to an Air-to-Ground

(A/G) radio as a means of controlling the VGLS(s).

3.1.1 Control Display Unit (CDU) Description

The CDU is located in the ATCT cab. The CDU provides the ATC with touchscreen capable of controlling up to 12 approaches with a maximum of 36 Visual Guidance Lighting Systems

(VGLSs). The CDU connects to the TCU in the ATCT equipment room, which in turn communicates with the RVIUs in the field via a unidirectional radio link. See Figure 3-1 for an example the CDU (front/back view).

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Figure 3-1. Example CDU (Front/Back Views)

3.1.2 Transmitter Control Unit (TCU) Description

The TCU is located in the ATCT equipment room. The TCU interfaces with the CDU to transmit the VGLS control commands sent by the ATC to the RVIU(s) installed in the field. The TCU translates the Function Command Codes (i.e., VGLS control functions) and Facility Codes (i.e., individual RVIU addresses) from CDU into a serial stream to transmit to the appropriate RVIU via unidirectional radio link. The TCU also provides the Airway Transportation Systems Specialist

(ATSS) the means of configuring the CDU to control the RRCS equipment during normal operation.

3.1.3 Remote VGLS Interface Unit (RVIU) Description

The RVIU(s) is located adjacent to the VGLS(s) in the field. Each RVIU is assigned a unique binary facility code. The RVIU interfaces with the VGLS equipment in the field to execute

Front Inside Rear

Front Inside Rear

6 September 2025 control commands from either the TCU or the A/G unit.

3.2 System Backward Compatibility Requirements

Figure 3-2 reflects the current RRCS configuration. The RRCS described within this specification shall be backward compatible as shown in Figure 3-3 and Figure 3-4.

Figure 3-2. Legacy RRCS Equipment (Tower and Field)

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Figure 3-3. Backward Compatibility Between New Tower Equipment and Legacy Field

Equipment

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Figure 3-4. Backward Compatibility Between New Field Equipment and Legacy Tower

Equipment

3.2.1 Tower Equipment Backward Compatibility

a. The CDU (located in the tower cab) and the TCU (located in the tower equipment room) shall be capable of interfacing with the legacy field equipment, which includes the

Receiver, Decoder, and Remote Radio Control Interface Unit (RRCIU), as shown above in

Figure 3-3.

b. Replacement of any legacy tower equipment (Switch Assembly Cabinet, Encoder Interface

Unit, or Transmitter Unit) shall require the replacement of all legacy tower equipment with the CDU and TCU.

3.2.2 Field Equipment Backward Compatibility

a. The RVIU (located in the field) shall be capable of interfacing with the legacy tower equipment, which includes the Switch Assembly Cabinet, Encoder Interface Unit, and

Transmitter Unit, as shown above in Figure 3-4.

9 September 2025

b. Replacement of any legacy field equipment (Receiver, Decoder, or RRCIU) interfaced with a single VGLS shall require the replacement of all legacy field equipment for that VGLS with an RVIU.

c. Replacing one set of legacy field equipment with an RVIU shall not require the replacement of all sets of legacy field equipment interfaced with other VGLSs.

3.3 RRCS Unit Requirements

3.3.1 Control Display Unit (CDU)

3.3.1.1 Functional Requirements

a. The CDU shall be a touchscreen.

b. The CDU shall perform a diagnostic self-check upon power-up.

c. In the event of an error during the diagnostic self-check an error code shall be displayed on the screen.

d. The CDU shall have independent controls to permit manual adjustment of the display brightness between 10%-100%.

e. The CDU shall be capable of confirming the communication link between the CDU and

TCU.

f. The CDU shall be capable of switching between Ground-to-Ground (G/G) Mode and Air-to-Ground (A/G) Mode.

3.3.1.1.1 Ground-to-Ground Mode

a. When set to G/G the CDU shall be the point-of-control for the system unless set to

Maintenance Mode via the TCU.

b. G/G Mode the CDU shall display all runway approaches and associated VGLSs at the airport.

c. In G/G Mode the ATC shall be capable of controlling the individual VGLSs.

3.3.1.1.2 Air-to-Ground Mode

a. When the ATC selects A/G Mode the CDU shall no longer be the point of control.

b. In A/G Mode the VGLSs at the airport shall be solely controlled by pilots via radio link.

3.3.1.2 Physical Requirements

a. The CDU shall be a direct replacement with the exact measurements as the FA-10266

Switch Assembly Cabinet.

b. The CDU touchscreen display screen shall be no larger than 9 inches x 9 ½ inches.

c. The CDU assembly shall be a NEMA 1 enclosure.

d. The CDU assembly shall weigh no more than 15 lb.

e. The CDU shall have an ON/OFF power switch located on the front of the unit with a protective cover.

f. The following shall be located on the back of the CDU:

1. The CDU shall be equipped with a USB-C port for backing up the current system configuration and any software upgrades.

10 September 2025

2. The CDU shall be equipped with a three prong plug to accept 120 VAC, 60 Hz input power.

3. The CDU shall be equipped with a ground lug.

4. The CDU shall be equipped with a means of physically interfacing to the TCU at a distance up to 500 feet.

3.3.2 Transmitter Control Unit (TCU)

3.3.2.1 Functional Requirements

a. The TCU shall be capable of receiving system configuration files or maintenance activities when connected to the Maintenance Terminal (MT).

b. The TCU shall be capable of pushing the system configuration files received from the MT to the CDU.

c. When the MT is disconnected from the TCU, the TCU shall automatically restore the CDU as the point of control.

d. The TCU shall be equipped with a radio transceiver to communicate with the individual

RVIUs.

3.3.2.2 Physical Requirements

a. The TCU assembly shall be a NEMA 1 enclosure.

b. The TCU shall be rack mountable in an EIA/ECA-310-E compliant 19-inch rack.

c. The TCU (including the rack mount) shall be no greater than 19 inches wide x 21 inches deep x 12 inches high.

d. The TCU shall weigh no more than 50 lb.

e. The TCU shall be equipped with an ON/OFF power switch.

f. The TCU shall use a Type N female coaxial connector to connect the radio transceiver to the antenna over a minimum of 500 feet of RG-214/U cable.

g. The TCU shall be equipped with a terminal block to accept 120 VAC, 60 Hz input power.

h. The TCU shall be equipped with a USB-C or equivalent as means of connecting to a MT

(i.e., laptop) to perform system configuration.

i. The TCU shall be equipped with a means for performing a reset of the unit.

j. The TCU shall be equipped with a transient protection device in accordance with Section

3.6.2, Lightning/Transient Protection.

k. The TCU shall be equipped with a means of physically interfacing to the CDU at a distance up to 500 feet.

3.3.2.3 Transmission Requirements

a. The TCU shall translate the Function Command Codes and Facility Codes from CDU into serial data streams to transmit to the appropriate RVIU via unidirectional radio link.

b. The Facility Code shall be transmitted with the least significant digit first and with bits inverted. (i.e., 10100 shall be transmitted as 11010).

c. There shall be a low bit of 20 ± 0.1 msec between each of the following signals: Start Code, Facility Code, Function Command Code, and Stop Code.

d. The Function Command Code duration shall be 110 ± 0.5 msec with each bit of 10 ±0.1 msec.

11 September 2025

e. The serial data streams shall be transmitted three (3) times within 1.3 seconds.

f. Following the Stop Code there shall be a low bit of 20 ±0.1 msec between each of the three

(3) transmitted messages.

g. The serial data streams shall be structured in accordance with Figure 3-5.

Figure 3-5. Serial Data Stream Format

h. The Function Command Code parameters shall be in accordance with Figure 3-6.

Figure 3-6. Function Command Code Format

3.3.3 Remote VGLS Interface Unit (RVIU)

3.3.3.1 Functional Requirements

a. The RVIU shall be equipped with a radio transceiver to receive VGLS control commands from the TCU via radio link.

b. The RVIU shall be capable of the interfacing with a A/G radio.

c. The RVIU shall be capable of executing commands received from the A/G radio when the

RRCS is in A/G Mode.

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d. The RVIU shall be equipped with a toggle switch within the cabinet and will include the following two options:

1. Maintenance (ignores commands from the TCU)

2. Remote (receives/executes commands from the TCU only)

e. The RVIU addressing shall be accomplished through the MT.

f. The RVIU shall have latching relays to provide 120 VAC control signals to the VGLSs

(MALS, MALSR, ODALS, PAPI, REIL, and VASI).

1. The RVIU shall interpret serial data from the TCU to activate the relays according to individual VGLS.

2. In the event of communication loss between the TCU and RVIU, or A/G and RVIU, the RVIU shall remain in the last commanded state until a new command is received.

g. The RVIU shall maintain the last commanded state after power loss.

3.3.3.1.1 RVIU to VGLS Interface

a. The RVIU shall be equipped with a single control terminal block capable of interfacing to all six (6) VGLSs in accordance with Table 3-1.

Table 3-1. RVIU Interface Capabilities

TERMINAL

BLOCK

EXTERNAL I/O CHARACTERISTIC PURPOSE

1 120 VAC output One (1) latching 120 VAC output, VGLS LOW intensity control

Selects VGLS LOW intensity lighting level

2 120 VAC output One (1) latching 120 VAC output, VGLS MED intensity control

Selects VGLS MED intensity lighting level

3 120 VAC output One (1) latching 120 VAC output, VGLS HIGH intensity control

Selects VGLS HIGH intensity lighting level

4 120 VAC output One (1) latching 120 VAC output, RAIL ON/OFF control

Selects RAIL lighting 'ON' and 'OFF'

5 120 VAC input One (1) input, A/G LOW status Control signal (LOW) from

A/G radio

6 120 VAC input One (1) input, A/G MED status Control signal (MED) from

A/G radio

7 120 VAC input One (1) input, A/G HIGH status Control signal (HIGH) from

A/G radio

b. The RVIU shall be equipped with a terminal block to accept 120 VAC, 60 Hz input power from the VGLS power source.

3.3.3.1.2 RVIU to A/G Radio Interface

a. The RVIU shall be equipped with a single terminal block to interface to the A/G radio.

b. The terminal block shall receive 120 VAC command signals (Low, Medium, High) from the A/G radio.

c. The terminal block shall provide 120 VAC power to the A/G radio.

d. The terminal block shall provide a neutral line to the A/G radio.

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3.3.3.1.3 Remote Control Logic

The remote control (A/G or G/G) logic outputs to the RVIU shall be in accordance with Table 3-2.

Table 3-2. RVIU Remote Control Logic

LOW INPUT MEDIUM INPUT HIGH INPUT

FLASHER

STATE/INTENSITY

X X X OFF

120 VAC X X ON (LOW)

120 VAC 120 VAC X ON (MED)

120 VAC 120 VAC 120 VAC ON (HIGH)

X = no voltage applied

3.3.3.2 Physical Requirements

a. The RVIU assembly cabinet (outside and inside) shall be a clear anodized aluminum

NEMA 4X enclosure.

b. The RVIU shall be equipped with a main power ON/OFF switch and indicator.

1. The power ON/OFF switch shall be located inside the unit and easily accessible.

2. The RVIU shall be equipped with a power light indicator that illuminates when the unit is powered ON.

c. The RVIU shall have a USB-C port to interface with the MT.

d. The RVIU shall be equipped with a means for performing a reset of the unit.

e. The RVIU shall be equipped with an accessible 15A GFCI outlet within the cabinet. The

GFCI outlet shall be independent of the power switch inside the cabinet.

f. The RVIU shall be equipped with an LED maintenance light.

g. The LED maintenance light shall be sufficient to illuminate the entire control cabinet.

h. The LED maintenance light shall have protection from damage due to inadvertent impact with standard maintenance tools.

i. The LED maintenance light shall have the protection of either a dedicated fuse housed and activated with a dedicated on/off switch independent of the power switch inside the cabinet.

j. The internal sheet metal shall be chemically filmed.

k. The RVIU cabinet shall be no greater than 24 inches wide x 6 inches deep by 24 inches high.

l. The RVIU assembly shall weigh no more than 50 lb.

m. The RVIU shall provide a minimum clearance of 5 inches between the bottom of the enclosure and the lowest mounting plate for cable termination provisions, grounding and bonding, and maintenance access.

n. Terminal blocks shall be located near the cable entrance to permit terminations of all external power and control wires feeding into the bottom of the RVIU cabinet.

o. The RVIU shall be capable of being vertically mounted.

p. The internal or external mounting bolts shall not protrude through the RVIU cabinet.

3.3.4 Maintenance Terminal (MT)

a. The MT shall perform system configuration and maintenance activities.

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b. The MT shall be a commercially available laptop computer that includes a USB-C port for interfacing to the TCU and RVIU.

c. The MT shall have the following two maintenance options: TCU and RVIU.

d. The MT shall be capable of initiating diagnostic commands at the TCU for both the TCU and CDU, and locally at the RVIU.

e. The MT shall be capable of initiating software field updates for the TCU and RVIU.

3.3.4.1 MT-to-TCU Functionality

The MT shall provide the user with the following options when the TCU is placed in Maintenance

Mode:

1. Create configurations

2. Upload/Download existing configuration file

3. Run diagnostics

▪ Software versions

▪ Transmitter performance

▪ TCU performance parameters

▪ Identifying failed LRUs

▪ Notifying user if config files are corrupt or untrustworthy

▪ Flagging invalid user inputs

a. The MT shall be capable of creating, reading, and editing configuration files on the TCU.

b. The MT shall be capable of uploading and downloading a complete configuration file from the TCU.

c. The MT shall require all users to provide a username and password.

d. The TCU, via the MT, shall be capable of setting individual VGLSs or individual approaches to OTS (Note: allows technicians to control only systems that are in OTS mode for trouble shooting purposes).

e. The TCU, via the MT, shall be capable of performing the following functions:

1. The TCU shall be capable of adding and removing individual RVIUs.

2. The TCU shall be capable of disabling ATC control of one or more individual

RVIUs for maintenance activities (i.e., out of service).

3. The TCU shall be capable of reenabling RVIUs following the conduct of maintenance activities.

3.3.4.2 MT-to-RVIU Functionality

The MT shall provide the user with the following options when the RVIU is placed in Maintenance

Mode:

1. Program 5-digit address

2. Allow for selection of preset VGLSs (MALS, MALSR, PAPI, ODALS, REIL, VASI)

3. Run diagnostics

▪ Last Command Received

▪ Power Status (input power and power supply readings)

▪ Operational Status

▪ Receiver Performance

▪ RVIU Performance Parameters

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3.3.5 Ancillary Equipment

3.3.5.1 Radio Requirements

a. The radio transceiver shall be capable of unidirectional transmission from the TCU to the

RVIU.

b. The radio transceiver shall use Frequency Modulation (FM).

c. The radio transceiver shall sequentially deliver tones of 2025 Hz (i.e., logic high) and 2225

Hz (i.e., logic low) to modulate the transmitter carrier frequency.

d. The radio transceiver shall be tuned to the same frequency as the local, point-to-multipoint system.

e. The radio transceiver shall use a single carrier frequency.

f. The modulation shall produce a minimum deviation of ±3 kHz of the FM carrier

(equivalent to 100 percent modulation in the 162 to 174 MHz band).

g. The radio transceiver frequency tolerance shall not exceed 1.5 ppm.

h. The radio transceiver radio frequency (RF) output frequency shall be programmable between 162-174 MHz.

i. Radio transceiver operating in the 162-174 MHz band shall adhere to the tuning and channel plan requirements per NTIA 4.3.7.

j. Radio transceiver channel spacing shall be 12.5 kHz.

k. Radio transceiver bandwidth shall not exceed 6.25 kHz.

l. The radio transceiver shall be capable of providing an RF output power that shall be adjustable from 1 to 5 Watts in 0.5 Watt increments (maximum) or dBm equivalent, into an output impedance of 50 ohms.

m. The radio transceiver shall meet the requirements for spurious response attenuation, adjacent channel selectivity, intermodulation rejection, and conducted spurious emissions per NTIA Manual 5.3.7A.

n. The carrier frequency shall be maintained within ±0.0005 percent of the reference frequency in ambient temperatures ranging from -40° C to +60° C.

o. Voltage Standing Wave Ratio (VSWR) shall meet the requirements specified in Table 3-3.

Table 3-3. VSWR Requirements

STATE VSWR

Initial Limits provided in Order JO-6650, Maintenance of Radio

Control Equipment for Plant Facilities, paragraph 301(b)(5)

Operating <= 2.0:1

3.3.5.2 Antenna Requirements

a. The TCU and RVIU antennas shall adhere to the requirements specified in Table 3-4:

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Table 3-4. TCU and RVIU Antenna Characteristics

PARAMETER CHARACTERISTIC

Gain 5.0dBi, maximum

Frequency Range As required by transceiver

Connector Style N-Type, female

b. The antennas shall be vertically polarized with a grounded radiator element for lightning protection.

c. The antenna transient suppression device shall be designed to withstand lightning transients superimposed on the AC input and output power lines characterized as 8 by 20 microseconds current surge of 5,000A with the subsequent power-follow current and voltage surge of 10 kV/microsecond minimum.

d. Antenna shall have performance characteristics as in Table 3-5 below:

Table 3-5. Antenna Performance Characteristics

ANTENNA PARAMETER PERFORMANCE REQUIREMENTS

Elevation beam width half-power points 50º degrees

Azimuthal radiation pattern (departure from true circle at peak) omnidirectional ±1.0dB

Elevation radiation pattern peak of main beam (ref 0° is horizon in elevation angle) 0° ±10° degrees

Maximum antenna voltage standing-wave ratio (VSWR) 2.00:1

Radio frequency power gain minimum

(reference to isotropic radiator) 0dB

Nominal terminal impedance 50Ω

Minimum RF power rating, (carrier power modulated 100 percent with 1 kHz tone) 25W

3.4 User Interface (UI) Requirements

The CDU user interface (UI) shall be designed as specified in the subsections below.

3.4.1 Main Screen

For requirements a-j refer to Figure 3-7.

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(a)

(b)

Figure 3-7. CDU Main Screen (a-b)

a. The CDU Main Screen shall be capable of displaying up to 12 runway approaches for a total of 36 VGLSs.

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b. The approach buttons, A/G button, and screen brightness buttons shall be oriented on the

CDU as shown in Figure 3-7.

c. The runway approach buttons, and corresponding VGLSs, shall be individually configurable per airport.

d. Each runway approach, A/G, and brightness buttons on the CDU Main Screen shall be individually selectable.

e. When an approach button is selected, the button shall appear depressed prior to transitioning to the corresponding Runway Approach Screen.

f. When no VGLSs are ON for a given approach, the corresponding runway approach button shall appear light grey and raised (i.e., not depressed).

g. Each VGLS shall display the individual system status to the right of the corresponding runway approach.

h. When an approach is active (i.e., one or more VGLSs are ON) the button shall appear green.

i. When an approach is set to out of service (OTS) at the TCU, the CDU shall display the approach button as flattened and dark grey with “OTS” in bold yellow text to the right of the corresponding approach button.

j. When an individual VGLS is set to OTS at the TCU, the CDU shall display “OTS” in yellow text to the right of the corresponding VGLS.

3.4.2 Runway Approach Screens

For requirements a-h refer to Figure 3-8.

Figure 3-8. Runway Approach Screen

a. The Runway Approach Screen shall be oriented as shown in Figure 3-8.

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b. Each runway approach button, that when selected, shall have a corresponding Runway

Approach Screen that will display the runway number and the associated VGLSs.

c. A “Back” button shall be provided to allow a user to return to the Main Screen.

d. The “Back” button shall appear light grey and raised.

e. When an individual VGLS is OFF, the OFF button shall appear medium grey and depressed.

f. All unselected buttons shall appear light grey and raised.

g. Each Runway Approach Screen shall be capable of displaying a maximum of three (3)

VGLSs.

h. The VGLSs on a given Runway Approach Screen shall be configured at the TCU using a pre-set list of the following six (6) systems: MALS, MALSR, ODALS, PAPI, REIL, and

VASI.

For requirements i-k refer to Figure 3-9.

Figure 3-9. Runway Approach Screen – OTS

i. In the event an individual VGLS is out of service (OTS) on a given approach, the OTS

VGLS ribbon buttons shall not be capable of being selected.

j. When a VGLS is OTS the ribbon buttons shall appear dark grey and flattened.

k. When a VGLS is OTS the text “OTS” shall be positioned to the right of the VGLS label in bold, yellow text.

3.4.2.1 MALSR Control Functionality

For requirements a-e refer to Figure 3-10.

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Figure 3-10. Example MALSR ON Control Functionality

a. The MALSR Ribbon shall provide the following control capabilities:

1. OFF

2. LOW, MED, and HIGH

3. RAIL ON and RAIL OFF

b. The OFF, LOW, MED, and HIGH buttons shall be interlocked to prevent the selection of more than one state.

c. The RAIL ON and RAIL OFF buttons shall be interlocked to prevent the selection of more than one state.

d. When selected, the LOW, MED, or HIGH and RAIL ON buttons shall be green and appear depressed.

e. The selection of LOW, MED, or HIGH shall not automatically cause the selection of RAIL

ON when RAIL OFF is depressed.

For requirements f-j refer to Figure 3-11.

Figure 3-11. Example MALSR OFF Control Functionality

f. When the MALSR system is selected OFF, the steady burning lights and RAIL shall turn off.

g. When the MALSR system is selected OFF with the RAIL ON button selected, the RAIL

ON button shall remain depressed and appear medium grey.

h. Following the above function, when returning to the Main Screen, the corresponding runway approach shall show “MALSR: OFF” and the “RAIL” label shall not be displayed.

i. When the MALSR system is selected ON (i.e., LOW, MED, or HIGH) while the RAIL

ON button is depressed, the steady burning lights and RAIL shall turn on.

j. When the MALSR system is selected ON (i.e., LOW, MED, or HIGH) while the RAIL

ON button is depressed, the selected intensity setting and RAIL ON buttons shall be green and appear depressed.

3.4.2.2 MALS/REIL/ODALS Control Functionality

For requirements a-c refer to Figure 3-12.

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Figure 3-12. Example MALS OFF Control Functionality

a. The MALS/REIL/ODALS Ribbons shall provide the following control capabilities:

1. OFF

2. LOW, MED, and HIGH

b. The OFF, LOW, MED, and HIGH buttons shall be interlocked to prevent the selection of more than one state.

c. When selected, the LOW, MED, and HIGH buttons shall be green and appear depressed.

3.4.2.3 PAPI/VASI Control Functionality

For requirements a-c refer to Figure 3-13.

Figure 3-13. PAPI/VASI Control Functionality

a. The PAPI/VASI Ribbons shall provide the following control capabilities:

1. ON

2. OFF

b. The ON and OFF buttons shall be interlocked to prevent the selection of more than one state.

c. When selected, the ON button shall be green and appear depressed.

3.4.3 A/G Mode

For requirements a-f refer to Figure 3-14 (a-b).

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Figure 3-14. A/G Mode Selection (a-b)

a. When the A/G button is selected on the Main Screen, a confirmation screen shall appear.

b. The A/G confirmation screen shall display two button options: “A/G” and “CANCEL”.

c. The “A/G” button option shall appear green.

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d. The “CANCEL” button option shall appear light grey.

e. The A/G confirmation screen shall include text stating “Please confirm your selection” positioned above the two button options.

f. The A/G confirmation screen shall include text stating “Note: Confirmation will turn all approaches to A/G” position below the two button options.

3.4.4 Auxiliary Screens

3.4.4.1 RRCS OTS

For requirements a-b refer to Figure 3-15.

Figure 3-15. RRCS OTS Screen

a. When the RRCS is set to out of service (OTS) at the TCU by the technician, the CDU shall no longer be capable of displaying or controlling the individual approaches.

b. When set to OTS, the CDU shall display “RRCS – OTS” centered within the screen with

OTS in yellow text.

3.4.4.2 Communication Failure

For requirements a-c refer to Figure 3-16.

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Figure 3-16. Communication Failure Screen

a. When a communication failure occurs between the CDU and TCU, the CDU shall no longer be capable of displaying or controlling the individual approaches.

b. When a communication failure occurs, the CDU shall display “COMM FAILURE” centered within the screen on top of a red “X”.

c. The red “X” shall extend the width and length of the screen.

3.4.4.3 Screen Cleaning Mode

For requirements a-f refer to Figure 3-17 (a-b).

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Figure 3-17. Screen Cleaning Mode (a-b)

a. The CDU shall be capable of being placed in Screening Cleaning Mode from the Main

Screen by selecting both brightness buttons simultaneously for a 3 second period.

b. Following the 3 second period, the CDU shall display a confirmation screen with two button options: “CONFIRM” and “CANCEL”.

g. The “CONFIRM” button option shall appear green.

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h. The “CANCEL” button option shall appear light grey.

d. Once “CONFIRM” has been selected, the CDU shall no longer be capable of displaying or controlling the individual approaches.

c. When in Screen Cleaning Mode, the CDU shall display “Screen Cleaning Mode” centered at the top of the screen.

d. When in Screen Cleaning Mode, the CDU shall also display an “X” in the upper right corner of the screen.

e. The “X” shall be used for exiting Screen Cleaning Mode when selected for a 3 second period.

f. Screen Cleaning Mode shall automatically time out after a period of 60 seconds and return to the Main Screen.

3.5 Human Factor Requirements

3.5.1 Luminance and Contrast

a. The touchscreen displays shall be capable of providing clear indication of equipment condition within the illumination levels consistent with the area of intended use.

b. The touchscreen displays shall have easy-to-use controls that provide multiple steps or continuously variable brightness adjustments.

c. The brightness control shall allow the user to vary the touchscreen display luminance from

10% to 100%.

d. The touchscreen display shall not be capable of being dimmed to a level beyond what cannot be differentiated from the OFF condition.

e. The touchscreen display shall have a foreground to background contrast ratio greater than

3:1; a contrast ratio of 7:1 is preferred.

f. The ambient lighting levels in areas of the display shall not degrade the visibility of signals on the touchscreen display.

g. The touchscreen shall have sufficient luminance transmission to allow the display to be clearly readable in the intended environment (i.e., ATCT cab). Discussion: A recent study by Post et. al (2024; DOT/FAA/TC-23/56) recommends the touch screen should have peak

D65 luminance of 700 cd/m2.

h. The touchscreen shall provide a positive indication to acknowledge the system response to the control action.

i. The touchscreen shall immediately display action feedback to the user.

j. The touchscreen shall be designed to minimize parallax problems.

3.5.2 Glare Control

a. The touchscreen shall be designed to minimize specular glare.

b. Anti-glare treatments shall not cause the touchscreen display to violate the requirements for luminance, contrast, and resolution that may impact task performance.

c. Hoods shall not be used to prevent or minimize glare on the touchscreen display.

d. The touchscreen display shall be designed to be legible in direct sunlight conditions.

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3.5.3 Visual Control-Indicator Relationship

The relationship of a control to its associated visual indicator and a visual indicator to its associated control shall be immediately apparent and unambiguous to the user.

Indicator-control relationships can be made apparent with one or more of the following: proximity, grouping, coding, demarcation, labeling, spacing, color-coding, insert panels, and panel relief.

3.5.4 Push Buttons

a. When the same buttons are used for different windows (i.e., “OFF”), the buttons shall be placed consistently in the same location.

b. Push button order shall be consistent throughout an application.

c. Related push buttons shall be placed together.

d. All push buttons shall have the same size and shape.

e. All push buttons shall have a text label.

f. Push button labels shall be consistent throughout an application and related applications.

g. Push button labels shall be short and unambiguous.

h. Color-coding shall conform to the following reserved meanings consistent with conventional associations for colors:

1. Red to indicate conditions such as no-go, error, failure, or malfunction.

2. Flashing red to indicate emergency conditions requiring immediate user action to avert personnel injury or equipment damage.

3. Yellow to indicate marginal conditions, alert users to situations where caution or rechecking is necessary, or notify users of an unexpected delay.

4. Green to indicate that a monitored process or unit of equipment is within tolerance, that a condition is satisfactory, or that it is all right to proceed with an operation or transaction.

5. White to indicate alternative functions or system conditions that do not have operability or safety implications.

6. Blue only as an advisory color.

i. Colors of push buttons shall be used consistently within a screen and within the application.

j. Color-coding of push buttons shall be redundant to some other means of coding, indicating an action, prompting a response, or distinguishing a visual element, not as the only means of conveying information.

k. The contrast between text and its background shall be sufficiently high to ensure readability of the text.

l. Buttons shall be positioned at least 10 millimeters apart from each other, as measured from perimeter to perimeter.

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3.6 System Requirements

The system shall be designed using modular construction concepts for ease of maintenance, employ plug-in printed wiring boards where practical, have interchangeable parts between like systems, have readily accessible test points for all major signals, and have lightning and transient protection. All energized surfaces and points (except test points on printed circuit boards) shall be insulated or covered to prevent electrical shock.

3.6.1 Service Entrance Clearance

Service entrance clearance shall be provided at the bottom and the side of the cabinet in accordance with the NFPA 70 and OSHA.

3.6.2 Lightning/Transient Protection

The equipment shall be designed and contain lighting/transient devices to withstand lightning transients applied at the power and control/status signal inputs and at the output lines (excluding remote maintenance monitoring).

3.6.2.1 Indoor Input Power

The equipment shall be designed to suppress switching transients and to withstand transient increases superimposed on the 120/240 VAC power line input voltage that reach a peak value of

500 VAC for ≤ 50 msec.

3.6.2.2 Outdoor Input Power and I/O Control and Status Signals

All input and output interface points to outdoor cabinets shall be designed to withstand lightning transients superimposed on the AC input and output power lines (excluding remote maintenance monitoring) characterized as 8 by 20 microseconds current surge of 5,000A with the subsequent power-follow current and voltage surge of 10 kV/microsecond minimum.

The power line connected to the outdoor equipment shall have a primary transient protection located externally at the bottom of the cabinet. The primary transient protection shall be located at the entry of the interface points. The secondary protection shall be provided on and inside each individual assembly and subassembly.

3.6.2.3 Transient Application

The equipment shall resume normal operation automatically with performance and operational functions unimpaired when an interruption or a shutdown is experienced due to a transient.

3.6.3 Electromagnetic Interference (EMI)

3.6.3.1 Conducted Emissions

For both indoor and outdoor equipment, the conducted interference levels on the power leads, control leads, signal leads, and interconnecting cables between parts shall not exceed the limits for CE102 as defined in MIL-STD-461 (Navy ground equipment class A3).

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3.6.3.2 Radiated Emissions

For both indoor and outdoor equipment, the radiated narrowband and broadband interference levels on the power leads, control leads, and signal leads shall not exceed the limits for RE102 as defined in MIL-STD-461 (Navy Mobil and Army ground equipment) over the frequency range from 100 kHz to 10 GHz.

3.6.3.3 Radiated Susceptibility

For both indoor and outdoor equipment, the radiated susceptibility interference of the system

(power leads, control leads, and signal leads) shall not exceed the limits for RS103 as defined in

MIL-STD-461 (Navy ground equipment) over the frequency range from 1 MHz to 1 GHz.

3.6.3.4 Conducted Susceptibility

For both indoor and outdoor equipment, conducted susceptibility shall not be greater than the limit for CS104 as defined in MIL-STD-461 using a frequency range of 10 kHz to 10 MHz.

3.6.4 Equipment Recovery

The equipment shall restart and initialize within 6 seconds to the last selected state automatically if an interruption or a shutdown is experienced.

3.6.5 Electrical Requirements

3.6.5.1 Power Loss

The interruption of primary power for short (less than 100 msec) or long durations shall not cause the system to restart in an undefined state upon restoration of power. All commands shall be stored and shall not require intervention or reactivation from the operator upon restoration of power.

Solenoid hold devices shall not be employed.

3.6.5.2 Harmonic

The RRCS shall meet the current harmonic distortion requirements stated in International

Electrotechnical Commission (IEC) 61000-3-2:2018.

3.6.5.3 Circuit Overload Protection

a. Current overload protection for the equipment shall be provided by fuses, circuit breakers, or other protective devices for primary circuits.

b. Overcurrent devices shall have a minimum of 10,000-Ampere Interrupting Capacity (AIC) rating.

c. Devices/components shall be protected from damage due to a loss of power or loss of one or more phases of power.

d. Overcurrent protective devices shall provide selective fault isolation rated for the available fault current calculated at the device location.

e. Available fault current shall be calculated from information concerning the facility in which the equipment is located.

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f. Series combination system overcurrent protection shall not be permitted.

3.6.5.4 Input Power Conditions

The equipment shall operate in accordance with the following power parameters:

a. Voltage 120/240 1-Phase; +10%, -15%;

b. Voltage phase imbalance, phase to phase: 5% as defined by Paragraph 3.8.2 of IEEE STD

141: Phase- voltage imbalance = Maximum deviation from average phase voltage /

Average phase voltage;

c. Frequency: Steady State 60 Hz +/– 3 Hz;

d. Voltage Harmonic Distortion: (1) 10% Voltage Total Harmonic Distortion (VTHD);

e. Voltage Harmonic Distortion: (2) 3% Any one Harmonic.

3.6.6 Mechanical Requirements

3.6.6.1 Installation

The equipment shall be designed for installation, removal and reinstallation without special tools unless approved by the FAA.

3.6.6.2 Construction

The equipment shall be constructed so that no fixed part will become loose during transport and during normal maintenance and operations functions.

3.6.6.3 Modular Construction

A module is defined as being two or more basic parts that form a functional assembly that uses a portion of a larger assembly or unit. The module is easily removed intact and replaced by plug-in, soldering, quick-disconnect, fastener, or equivalent means.

All electronic, electrical, and mechanical components shall be designed and constructed to minimize skill, experience, and time necessary to disassemble, assemble, and maintain them.

Similar functions shall be performed using identical modules wherever practical, and preference will be given to designs which afford component replicability.

3.6.6.4 Lowest Replaceable Units (LRUs)

a. LRUs shall be removable and replaceable.

b. LRU Mounting devices shall provide the capability of the LRU to be repeatedly installed and removed without degrading performance.

c. Where LRU plug-in modules, sub-assemblies, and assemblies are used, they shall be capable of being inserted in the proper location when correctly oriented without damage to equipment or parts being engaged.

d. LRU plug-in modules and assemblies shall be designed to prevent insertion into the improper location or incorrect orientation.

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3.6.7 LRU Interchangeability

All new LRUs shall be interchangeable in form, fit, and function without mechanical adjustment.

3.6.8 Test points

3.6.8.1 Test points

Test points shall be provided to monitor all signals used during checkout, alignment, calibration, or during preventive maintenance procedures.

3.6.8.2 Location

Test points shall not be located in compartments with exposed voltages of 24 DC volts or more.

3.6.8.3 Safety

All test points shall be located as to preclude accidental shock to personnel engaged in normal operating or maintenance activities.

3.6.8.4 Accessibility

The removal of components, modules or circuit cards shall not be required to gain access to test points or adjustments.

3.6.8.5 Circuit card – test point front access

Test point controls and indicators mounted on printed wiring boards shall be accessible from the front of the circuit card assembly without the use of extender boards.

3.6.9 Derating of Electronic Parts

The electronic parts and materials selected shall be used within their electrical ratings and environmental capabilities (e.g. any ambient or hot spot temperatures, voltage, current, or power dissipation). A derating of 80% shall be implemented to assure the required equipment reliability within the specified operating conditions.

3.6.10 Enclosures

Enclosures shall have mounting means external to the cabinet cavity, provisions for locking, and shall not have conduit hubs or knockouts. Space shall be provided in the cabinet for all external cable connections. Terminal blocks shall be located near the cable entrance to permit terminations of all external power and control wires feeding into the cabinet. Mounting lugs or bolts shall be provided on the back of the cabinets for mounting the cabinets vertically. Internal and external mounting bolts shall not protrude through the cabinet.

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3.6.11 Enclosure Finishes

3.6.11.1 Indoor Enclosures

The indoor enclosure finishes shall be painted with high, solid Polyurethane Type semi-gloss;

color brown No. 20372 with texture, in accordance with FAA-STD-595.

The painted surfaces shall withstand the environmental conditions defined by the equipment specification for the entire service life of the equipment without flaking, cracking, or allowing any corrosion of the underlying surface. Leaded paint or paints containing isocyanates and hazardous substances shall not be used.

3.6.11.2 Outdoor Enclosures

The outdoor enclosures, including the door, shall be anodized in accordance with MIL-A-8625.

3.6.12 Door Gasket

If gaskets are used:

a. The total number of strips used shall not exceed four;

b. The vertical and horizontal runs shall be continuous except where the vertical strips meet the horizontal strips;

c. The horizontal strips shall overlap the vertical strips;

d. The RVIU cabinet gaskets shall be EMI-rated for the environment;

e. Indoor cabinets shall have either continuous molded gaskets or strip gaskets;

f. Outdoor cabinets shall have continuous molded gaskets; and

g. The gaskets shall be neoprene.

h. The gaskets shall be resistant to deterioration such as cracking, hardening, or softening under environmental conditions the equipment will operate in.

3.6.13 Cabinet Door

All cabinet doors shall open from the right side of the cabinets.