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DOT/FAA/TC-16/5

Federal Aviation Administration William J. Hughes Technical Center Aviation Research Division Atlantic City International Airport New Jersey 08405

Non-Transponder-Based Automatic Dependent Services -Broadcast (ADS-B) Downlink Format 18 (DF=18) Virtual Target Injection

January 21, 2016

Final Report

This document is available to the U.S. public through the National Technical Information Services (NTIS), Springfield, Virginia 22161.

This document is also available from the Federal Aviation Administration William J. Hughes Technical Center at http://actlibrary.tc.faa.gov/.

U.S. Department of Transportation Federal Aviation Administration

http://actlibrary.tc.faa.gov/

NOTICE

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The United States Government assumes no liability for the contents or use thereof. The United States Government does not endorse products or manufacturers. Trade or manufacturer's names appear herein solely because they are considered essential to the objective of this report. The findings and conclusions in this report are those of the author(s) and do not necessarily represent the views of the funding agency. This document does not constitute FAA policy. Consult the FAA sponsoring organization listed on the Technical Documentation page as to its use.

This report is available at the Federal Aviation Administration William J. Hughes Technical Center’s Full-Text Technical Reports page: http://actlibrary.tc.faa.gov/ in Adobe Acrobat portable document format (PDF).

Emerging Surveillance Technologies Laboratory ii

http://actlibrary.tc.faa.gov/

Technical Report Documentation Page 1. Report No.

DOT/FAA/TC-16/5 2. Government Accession No. 3. Recipient's Catalog No.

4. Title and Subtitle

Non-Transponder-based Automatic Dependent Services-Broadcast (ADS-B) Downlink Format 18 (DF=18) Virtual Target Injection Technical Report

5. Report Date

January 21, 2016 6. Performing Organization Code

ANG-E55 & ANG-C33 7. Author(s)

Oren Weiss, Principle Investigator & Hardware Design Engineer, Emerging Surveillance Technologies Laboratory, Air Traffic Systems T&E Services Division, ATC Surveillance Branch, [email protected]

Daniel Lovelace, Aeronautical Engineer, Engineering Development Services Division, Surveillance Branch, [email protected]

8. Performing Organization Report No.

9. Performing Organization Name and Address

U.S. Department of Transportation Federal Aviation Administration Engineering Development Services Branch, ANG-C33 / Air Traffic Systems T&E Services Branch, ANG-E55 William J. Hughes Technical Center Atlantic City International Airport, NJ 08405

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

12. Sponsoring Agency Name and Address

U.S. Department of Transportation Federal Aviation Administration Portfolio Management & Technology Development Office William J. Hughes Technical Center Atlantic City International Airport, NJ 08405

13. Type of Report and Period Covered

Technical Report October 2015 – December 2015 14. Sponsoring Agency Code ANG-C

15. Supplementary Notes 16. Abstract The William J. Hughes Technical Center’s (WJHTC) Engineering Development Services Division’s and Air Traffic Systems T&E Services Division’s Surveillance Branches jointly conducted a multi-phased controlled experiment to verify that the Surveillance and Broadcast Services System (SBSS) processes non-transponder-based (Downlink Format 18 (DF=18)) 1090 MHz Extended Squitter (1090ES) messages in compliance with published standards.

Because this testing involved the injection of a virtual target into the National Airspace System (NAS), the test team placed special emphasis on minimizing any risk to the NAS. A virtual 1090ES Automatic Dependent Services-Broadcast (ADS-B) target was created and injected into the SBSS using specialized test equipment so that it would only be received by a single carefully selected SBS ground-based Radio Station (RS) and would not present a hazard to pilots operating within the area. The target’s quality parameters were also configured lower to preclude display by Air Traffic Control (ATC) automation systems.

Tests verified that the network-based UDP (Universal Datagram Protocol) FAA-Category 33 (CAT033) target report packets captured at WJHTC’s Service Delivery Point (SDP) were created from the injected virtual targets, and non-transponder-based 1090ES target messages (DF=18) were properly formatted, processed at the required rate, and essentially indistinguishable from the similar transponder-based (DF=17) target messages.

17. Key Words

Surveillance and Broadcast Services, Surveillance, SBS, Automatic Dependent Surveillance-Broadcast, 1090ES, ADS-B, Non-transponder-based ADS-B, DF=18, DO-260, DO-260A, DO-260B, SBS System, SBSS, FAA-Category 33, CAT033, WJHTC

18. Distribution Statement

This document is available to the U.S. public through the National Technical Information Service (NTIS), Springfield, Virginia 22161. This document is also available from the Federal Aviation Administration William J. Hughes Technical Center website at http://actlibrary.tc.faa.gov.

19. Security Classification (of this report)

Unclassified 20. Security Classification (of this page)

Unclassified 21. No. of Pages

9 22. Price

N/A Form DOT F 1700.7 (8-72) Reproduction of completed page authorized

Emerging Surveillance Technologies Laboratory iii

mailto:[email protected]

mailto:[email protected]

This page intentionally left blank.

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APPROVAL SIGNATURES

DOCUMENT TITLE: NON-TRANSPONDER-BASED AUTOMATIC DEPENDENT SERVICES-BROADCAST (ADS-B) DOWNLINK FORMAT 18 (DF=18) VIRTUAL TARGET INJECTION TECHNICAL REPORT

Approved: Michael Prata, Manager, Air Traffic Systems Test & Evaluation Services Division, ATC Surveillance Branch, ANG-E55

Date: January 21, 2016

Approved: Stewart Searight, Manager, Engineering Development Services Division, Surveillance Branch, ANG-C33

Date: January 21, 2016

Emerging Surveillance Technologies Laboratory v


Emerging Surveillance Technologies Laboratory vi

TABLE OF CONTENTS

1 INTRODUCTION 1

1.1 Purpose 1

1.2 Background 1

2 EXPERIMENTAL APPROACH 3

2.1 Experiment Methods and Materials 3

2.1.1 Equipment and Experimental Setup 3

2.1.2 Risk Mitigation 5

2.1.3 Experiment Methodology 6

3 RESULTS 7

4 CONCLUSIONS 7

5 REFERENCES 9

Emerging Surveillance Technologies Laboratory vii

LIST OF FIGURES

Figure 1-1 Surveillance and Broadcast Services System Architecture 2

Figure 2-1 Virtual Target Generator 4

Figure 2-2 SBSS Service Delivery Point Data Description 5

LIST OF TABLES

Table 2-1 Transmission Testing Phases 6

Emerging Surveillance Technologies Laboratory viii

LIST OF ACRONYMS

1090ES 1090 MHz Extended Squitter A/V Aircraft/Vehicle AA Aircraft Address ADS-B Automatic Dependent Surveillance-Broadcast ANG-C FAA NextGen Portfolio Management & Technology Development Office ANG-C33 Engineering Development Services Division, Surveillance Branch ANG-E55 Air Traffic Systems T&E Services Division, ATC Surveillance Branch AST ATC Surveillance Team ATC Air Traffic Control ATCRBS Air Traffic Control Radar Beacon System CAT033 FAA-Category 33 Data Format (ADS-B Surveillance Messages) CF Format Code for Downlink Format 18 ADS-B Messages CFR Code of Federal Regulations CS Control Station CTV Composite Traffic Volume dBm Decibels referenced to one milliwatt DF Mode S/ADS-B Message Downlink Format DO Document DOT Department of Transportation FAA Federal Aviation Administration GPS Global Positioning System KSN Knowledge Services Network Mode S Mode Select MOPS Minimum Operational Performance Standards MSL Mean Sea Level N/A Not Applicable NAS National Airspace System NextGen Next Generation Air Transportation System NOC Network Operations Center NTIS National Technical Information Service RF Radio Frequency RS Radio Station RTTS Real-Time Tracking System SBS Surveillance and Broadcast Services SBSS Surveillance and Broadcast Services System SDP Service Delivery Point SV Service Volume T&E Test and Evaluation TIS-B Traffic Information Services-Broadcast TR Test Report UDP Universal Datagram Protocol VFR Visual Flight Rules VTG Virtual Target Generator WJHTC William J. Hughes Technical Center

Emerging Surveillance Technologies Laboratory ix


Emerging Surveillance Technologies Laboratory x

EXECUTIVE SUMMARY

The William J. Hughes Technical Center’s (WJHTC) Engineering Development Services Division’s and Air Traffic Systems T&E Services Division’s Surveillance Branches jointly conducted a multi-phased controlled experiment to verify that the Surveillance and Broadcast Services System (SBSS) processes non-transponder-based (Downlink Format 18 (DF=18)) 1090 MHz Extended Squitter (1090ES) messages in compliance with published standards.

Because this testing involved the injection of a virtual target into the National Airspace System (NAS), the test team placed special emphasis on minimizing any risk to the NAS. A virtual 1090ES Automatic Dependent Services-Broadcast (ADS-B) target was created and injected into the SBSS using specialized test equipment so that it would only be received by a single carefully selected SBS ground-based Radio Station (RS) and would not present a hazard to pilots operating within the area. The target’s quality parameters were also configured lower to preclude display by Air Traffic Control (ATC) automation systems.

Tests verified that the network-based UDP (Universal Datagram Protocol) FAA-Category 33 (CAT033) target report packets captured at WJHTC’s Service Delivery Point (SDP) were created from the injected virtual targets, and non-transponder-based 1090ES target messages (DF=18) were properly formatted, processed at the required rate, and essentially indistinguishable from the similar transponder-based (DF=17) target messages.

Emerging Surveillance Technologies Laboratory xi

ACKNOWLEDGEMENTS

The authors would like to thank everyone involved in planning, executing, and evaluating the experiment.

FAA William J. Hughes Technical Center – Paul Dawson, Kevin Szagala, Andy Leone, Michael Prata, Stuart Searight, Michael McNeil, Jack Brooks, Joe Pagano, Thomas Healy

Regulus Group, LLC – Thomas Pagano, Chuck Greenlow, Michelle O’Leary

Spectrum Software Technology, Inc. – Robert Bastholm

Emerging Surveillance Technologies Laboratory xii

1 Introduction

1.1 Purpose The purpose of this test is to verify the proper receipt and formatting of non-transponder-based Automatic Dependent Surveillance-Broadcast (ADS-B) messages at the Service Delivery Point (SDP) for Surveillance and Broadcast Services (SBS).

1.2 Background ADS-B is a Global Positioning System (GPS)-based Air Traffic Control (ATC) surveillance technology that allows avionics to broadcast an aircraft’s identification, position, altitude, velocity, and other information to support ATC services in Terminal and En Route airspace and in airport surface operations. The Federal Aviation Administration (FAA) ADS-B Out Final Rule1 requires aircraft operating in certain airspace be equipped with ADS-B Out avionics that meet the standards in RTCA Document 260 (DO-260B)2 by January 1, 2020.1

The suite of ADS-B avionics, ground-based receivers, control stations, and service delivery network is collectively known as the Surveillance and Broadcast Services System (SBSS), which is the core of the Federal Aviation Administration’s NextGen program. As illustrated in Figure 1-1, the SBSS consists of four distinct sections:

• The Ground Segment, which consists of more than 800 ground-based ADS-B radio stations located throughout the United States

• The Network Segments, which encrypt and transmit the data to the control segment and from the control segment to the Automation and Monitor Segment

• The Control Segment, which resides in the Network Segment and processes the surveillance data and system status reports

• The Automation and Monitor Segment, which delivers the data via Service Delivery Points (SDPs) to Air Traffic Control (ATC) Automation Systems and FAA Service Monitoring Stations at the William J. Hughes Technical Center (WJHTC) and Mike Monroney Aeronautical Center.

The DO-260 MOPS allows for two distinct types of airborne ADS-B Out messages for civilian use. The vast majority of ADS-B Out installations will be coupled with Mode S transponders, where the ADS-B Message Generation function, the Radio Frequency (RF) modulator, and 1090MHz transmitter reside in the transponder itself. This system is known as transponder-based 1090ES ADS-B, and it represents most of the ADS-B avionics equipage, especially in the commercial sector. For these aircraft, the Downlink Format (DF) field “shall be set to DF=17 (binary 1 0001) for all ADS-B message transmissions.” (DO-260, §2.2.3.2.1.1.b). The “DF” field is the first field in all 1090 MHz downlink formats and provides the transmission descriptor coded in accordance with RTCA Document DO-181C.3

1 The DO-260B Minimum Operational Performance Specifications (MOPS) were issued on December 13, 2011, superseding DO-260 Change 1, issued on June 27, 2006. All applicable ADS-B standards that are referenced in this report remain unchanged in the superseded versions, up to and including DO-260B. For the sake of clarity and expediency, the specifying MOPS shall henceforth be referred to only as DO-260.

Emerging Surveillance Technologies Laboratory 1

Figure 1-1 Surveillance and Broadcast Services System Architecture

The DO-260 MOPS also recognized the need for the generation of ADS-B Out messages in aircraft that are not equipped with Mode S transponders, as for much of general aviation. The MOPS specifically allows for the generation of ADS-B Out messages in these aircraft that may only have Mode A/C Air Traffic Control Radar Beacon System (ATCRBS) transponders. For these aircraft, “the DF field shall be set to DF=18 (binary 1 0010) for all ADS-B message transmissions from transmission devices that are not Mode S transponder based systems.” (DO-260, §2.2.3.2.1.1.c).

Because DF=18 messages are also used for Traffic Information Services-Broadcast (TIS-B), the three-bit Code Format (CF) field serves to differentiate DF=18 ADS-B messages and DF=18 TIS-B messages. DF=18, CF=0 indicates that the Aircraft Address (AA) field holds the aircraft’s permanent 24-bit International Civil Aviation Organization (ICAO) address (DO-260, §2.2.3.2.1.5). DF=18, CF=1 is used for all other non-transponder-based ADS-B message generation where the AA field holds another kind of address for the transmitting ADS-B client, which can be a self-assigned “anonymous” airborne target address, a surface vehicle address, or a fixed obstruction address. “ADS-B messages from ADS-B transmitting sub-systems that are not based on Mode S transponders shall use CF=0 or 1, according to the type of address conveyed in the AA field” (DO-260, §2.2.3.2.1.3).

The target’s information, contained in FAA-Category 33 (CAT033) reports, is distributed via network-based Universal Datagram Protocol (UDP) multicast packets to endpoints called Service Delivery Points (SDPs). These CAT033 messages are grouped using their GPS location into geographic volumes of airspace known as Service Volumes (SVs). There are four different types of SVs in the National Airspace System (NAS): En Route, Terminal, Surface, and Composite


Traffic Volumes (CTVs). En Route SVs comprise the same geographic regions as En Route airspaces. Terminal SVs are centered on major airports (Class A, B, C, or D airspace). Surface SVs are also located at some airports and typically contain targets that transmit surface position reports. These are either aircraft reporting an On-Ground state or surface vehicles that maneuver on the Airport Operations Area. CTVs are collections of SVs from which the data from multiple SVs is aggregated.

2 Experimental Approach

2.1 Experiment Methods and Materials For expedience and avoidance of the high costs associated with live test flights, the test targets were generated virtually with the Virtual Target Generator4 (VTG) test device, pictured in Figure 2-1. This strategy does, however, introduce certain risks to the NAS and the safety of other pilots in the area, so the experiment included carefully chosen mitigation strategies as outlined in Section 2.1.2.

For this experiment, the test team created “virtual” test targets in a multi-phased approach using various combinations of DF, CF and the airborne/on-ground states. These messages were transmitted via carefully attenuated RF signals near a live ground-based SBS radio so that the signal would be received and processed by the ground-based ADS-B Radio Station (RS). Steps were taken to make the flight characteristics of the virtual target as real as possible, while at all times ensuring that there were no risks to either the NAS or nearby traffic. Remote monitoring of the SBS SDP at the WJHTC using the Real-Time Tracking System (RTTS) ensured the target was transmitted, received, and processed by the SBSS. The recorded network capture files were then post-processed and analyzed for compliance to DO-260.

2.1.1 Equipment and Experimental Setup

While the current regulatory framework prohibits the transmission on frequencies used by aviation, after extensive testing, the WJHTC Surveillance Group has been granted a waiver from the FAA Spectrum Office and the Federal Communications Commission to transmit on aviation frequencies using the VTG. The VTG is a low-power 1090ES transmitter, compliant with DO-260 standards, that supports myriad aspects of ADS-B testing. The VTG provides a safe and cost-effective way to conduct the multiple ADS-B equipped aircraft encounters required to exercise ADS-B systems and prepare for development and testing of future ADS-B applications.


The VTG’s design allows it to take in live GPS signals and create one or more virtual targets that can be can be flown via joystick, independently or in formation. Its low transmission power keeps the virtual targets locally confined to the unit or area under test. It provides flexibility in scenario development as it allows ADS-B message fields to be set in nearly any configuration.

Figure 2-1 FAA Virtual Target Generator

A Garmin GTX-330D DO-260B compliant transponder was used as a “control” transponder to ensure the VTG’s output power was sufficient to reach the RS and verify proper equipment configuration. A Novatel GPS-702 pinwheel antenna, split and amplified, provided the GPS source to all the equipment used in the testing and monitoring. Local RF monitoring was achieved through the use of a Garmin GDL-88 transponder and a laptop computer running Universal Flight Recorder software, which acts as a Cockpit Display of Traffic Information for a variety of ADS-B input sources.

As illustrated in Figure 2-2, the SDP at the WJHTC receives the same critical SBS data that is delivered to automation systems around the country. Because of this, the WJHTC SDP was selected as the location to capture the target data for analysis. Remote monitoring at the WJHTC was achieved using the RTTS, which monitors the SBS Service Delivery Point and displays targets in real time. Using Wireshark (an open-source network analysis tool) and the WJHTC-developed CAT033 dissector plug-in, analysis was performed on raw network capture data collected and archived by the Surveillance Group. The collection and archiving of the SDP data


feed is described in the Surveillance and Broadcast Services (SBS) Automatic Dependent Surveillance-Broadcast (ADS-B) Flight Data Archive Process Guidelines, available by request on the ANG-E55 Knowledge Services Network (KSN) site.5

All test tools used in both the generation of ADS-B messages and the tools used to process and analyze the SDP output have been subjected to rigorous verification and validation testing formalized in the ANG-E55 Test Tool Accreditation Plan/Process, available by request on the ANG-E55 KSN site.6

Figure 2-2 SBSS Service Delivery Point Data Description

2.1.2 Risk Mitigation

Of utmost importance in the conduct of this test was the mitigation of risks to the NAS, controllers, and other aircraft. To that end, the test team selected an SBS ground-based RS outside of controlled airspace, RS-41, in West Creek, NJ, near Eagles Nest airport (31E). The virtual test-target was confined to Class G airspace, which has a 700’ Mean Sea Level (MSL) ceiling, though the target would never report a position higher than 200’ MSL. Testing took place where Visual Flight Rules (VFR) were in effect and visibility was clear. The test target was always broadcasting a Mode 3/A code of 1200 to indicate that it was operating under VFR, and test personnel monitored the UNICOM frequency to allay any concerns of other VFR pilots in the area.

ADS-B Reports, WAM Reports, Service Status Reports

TIS-B Reports, Service Status Reports, FIS-B Reports, TIS-B/ADS-R Service Status Reports

Critical SBS

SDP

SDP Essential SBS

ADS-B, WAM, Service Status, ADS-R ACK/NACK and TIS-B/ADS-R Service Status Reports

SBS Monitor

ATC Automation

= Demarcation Point


The VTG has been thoroughly tested, and the messages it transmits are DO-260 compliant in all ways with the exception of transmit power. The transmit power was artificially attenuated to +5 dBm (about 4 mW) to ensure that only the nearby radio station would pick up its transmissions and that no air-to-air transmissions to commercial aircraft could occur. At this transmission level, the free-space loss would make the virtual test target invisible to nearly any receiver outside of a direct line of site or more than a few hundred meters away. Additionally, RS-41 is surrounded by a high and dense tree line, which also contributed to keeping the virtual test target signals locally confined.

The test team also configured the VTG to generate position integrity and accuracy parameters, i.e., Navigation Integrity Category, Navigation Accuracy Category for Position, and Navigation Accuracy Category for Velocity, below the required automation system minimums. Even with all the other safeguards taken to ensure the virtual test target would not interfere with NAS operations, degrading these values below acceptable minimums ensured that no controller could see the virtual test target.

While the virtual test target can be configured to climb as high as 700’ without entering Class E airspace (which is also not controlled for VFR aircraft but is monitored by ATC), the virtual test target was kept under 200’. Furthermore, to ensure no conflicts with the nearby private airport, the VTG manipulated the live GPS input to place the virtual test target one mile to the south, ensuring no conflicts with the pattern of the nearby private airport.

2.1.3 Experiment Methodology

The basic methodology was to construct a controlled experiment whereby only a single variable was manipulated for each test phase, as depicted in Table 2-1. Using the FAA Emerging Surveillance Technologies Mobile Laboratory as a base for the antenna and power supply for avionics, the van was parked about 100 meters from the ground-based radio tower, with 1090 MHz and GPS antennas installed on the roof.

Table 2-1 Transmission Testing Phases

1090ES Transmitter DF Tx Power State

GTX-330D 17 +55 dBm On-Ground

GTX-330D 17 +55 dBm Airborne

GTX-330D 17 +5 dBm Airborne

VTG 17 +5 dBm Airborne

VTG 18 +5 dBm Airborne

VTG 18 +5 dBm On-Ground

The testing began with the transmission of the DF=17 transponder, a DO-260 compliant Garmin GTX-330D, which was utilized as the “control” in this experiment. After establishing the control


transponder was operating as designed, its RF transmit power was then attenuated to the same output power as the VTG (5 dBm). This phase ensured that the transmit power level was sufficient for reception by the ground-based RS. Remote verification from the WJHTC confirmed that the output power level was sufficient and CAT033 messages were generated according to requirements. Because the control transponder did not generate CAT033 messages when transmitting at full power due to its “On-Ground” state, no other DF=17 variant phase was tested in the “On-Ground” state. This behavior was expected and conforms to published standards. The Garmin GTX-330D was then turned off and replaced with the Virtual Target Generator for the remaining experiment phases.

The VTG, configured to output messages similar to the Garmin GTX-330D, was then turned on. The virtual test target’s transmissions were confirmed both locally and at the WJHTC SDP. To gather a sufficient quantity of CAT033 reports for analysis, the VTG was left running in each phase for 15 to 20 minutes with 15 to 20 minutes of no transmissions between configuration changes. The recorded data was then post-processed and analyzed at the WJHTC.

3 Results The CAT033 messages created by the SBSS from the transmissions of the Garmin GTX-330D and the VTG were analyzed from raw network capture files recorded and archived by the Surveillance Branch of the Engineering Development Services Division (ANG-C33) at the WJHTC using tools developed in-house. The tests verified that the CAT033 target reports captured at the WJHTC SDP were properly created from the virtual target’s transmissions, the non-transponder-based 1090ES target messages (DF=18) were processed in accordance with DO-260 MOPS and were determined to be indistinguishable from the similarly created transponder-based (DF=17) target messages.

Additionally, because of the lack of a surface service volume where the live injection testing was conducted, no CAT033 messages (either DF=17 or DF=18) from aircraft that reported an On-Ground state were observed at the SDP. This is expected behavior for DO-260 compliancy.

4 Conclusions While only a single target was transmitted into a single ground-based radio station, the multi-phase approach produced reasonably sufficient data to conclude that non-transponder-based ADS-B targets are being properly interpreted and processed by the SBSS, and CAT033 target reports are being generated in accordance with DO-260 requirements.

This experiment, however, does not verify that a non-transponder-based ADS-B target will reach ATC displays. It does verify that properly formatted non-transponder broadcasts that are received by the ground-based radio station are processed by the SBSS and CAT033 messages are generated that are equivalent to the DF=17 transponder-based messages. It is expected that these messages would be delivered to ATC if integrity and accuracy metrics were at or above the minimum thresholds in places where ADS-B data is delivered to ATC. SVs where validation is


active could inhibit such messages depending on the validation criteria. Verifying output to ATC would need to consider these issues.


5 References

1 Automatic Dependent Surveillance-Broadcast (ADS-B) Out Performance Requirements to Support Air Traffic Control (ATC) Service; Final Rule, 14 CFR Part 91, May 28, 2010

2 Minimum Operational Performance Standards for 1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic Information Services (TIS-B), RTCA DO-260B, December 13, 2011

3 Minimum Operational Performance Standards for Air Traffic Control Radar Beacon System/Mode Select (ATCRBS/Mode S) Airborne Equipment, RTCA DO-181C, June 12, 2001

4 Apparatus and Method to Generate and Detect Virtual Targets, U.S Patent Number 8,604,965 B2, December 10, 2013

5 Surveillance and Broadcast Services (SBS) Automatic Dependent Surveillance-Broadcast (ADS-B) Flight Data Archive Process Guidelines V1.0, AST-D3-GDE-003, June 21, 2010

6 Test Tool Accreditation Plan/Process V2.0, AST-B3-PLN-003, September 30, 2011


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William J. Hughes Technical Center Federal Aviation ... · Federal Aviation Administration B. ... ANG-C33 Engineering Development Services Division, ... Spectrum Software Technology,