TCAS Resolution Advisory Monitoring System (TRAMS) Carl B. Jezierski Airborne Team AJP-651

Federal AviationAdministrationTCAS Resolution

Advisory Monitoring System (TRAMS)

Carl B. Jezierski

Airborne Team AJP-651

Research & Technology Development

15 October 2008

Aerospace Control and Guidance Systems Committee Meeting #102

2

Federal AviationAdministration

ACGSC Meeting #102 Briefing

Topics

• A Brief History of TCAS • TCAS Theory of Operation• TCAS and the ATC Mode S Radar Environment • Purpose and Requirements for TCAS Monitoring• TRAMS Architecture• TRAMS Data Collection and Processing• TRAMS Data Flow• TRAMS Deployment

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• TCAS V6.04(a)• TCAS V7.0 RTCA DO-185A• Recent Logic Changes (1)

– V7.1 RTCA DO-185B• RA Reversal Logic “SA01”• AVSA

• Recent Logic Changes (2)– Hybrid Surveillance

• TRAMS – TCAS Resolution Advisory Monitoring System• RTCA SC-218 (Future ADS-B/TCAS Relationships)

– Systems engineering analysis plan – September 08– Perform systems engineering analysis – July 09

• TCAS on UAS

A Brief History of TCAS

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• Airborne Platform– Transponder-based

• TCAS I Traffic Alerts (TA) Only

• TCAS II TA and Resolution Advisory (RA) Generation– Coordination of vertical maneuvers with other aircraft– 18 second RA broadcast transmitted

TCAS Theory of Operation

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Purpose and Requirements for TCAS Monitoring

The TCAS RA Monitoring System (TRAMS) is a new distributed ground-based system that will capture airborne RA communications and related surveillance data in real-time and transmit this information daily to a central facility for analysis and archive. The overall goal of TRAMS is to enable analysis of TCAS performance and facilitate changes in the airspace. Specifically, the mission objectives are to:

• Comply with the Safety Management System requirement to monitor new systems introduced into the NAS environment to protect against NAS performance degradation.

• Provide a database of actual Resolution Advisories (RA) and associated surveillance data for post analysis of TCAS operational performance.

• Provide a database of selected surveillance data for future research.

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TCAS and the ATC Mode S Radar Environment

• Types– Terminal radar (60 nm, 360° every 4.75 seconds)– Enroute radar (200 nm, 360° every 12 seconds)

• Default Programming – Ground site interrogates the aircraft’s transponder to determine

equipage

• Site Specific Programming– If RA broadcast detected, interrogate the transponder for the RA

specifics

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TRAMS Architecture

FAA Technical CenterTRAMS Central Site

TRAMSRemote Site

CollisionEvent

Resolution Advisory (RA)and

Surveillance Data

TRAMSRemote Site

TRAMSRemote Site

TRAMSRemote Site

TRAMSRemote Site

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TRAMS Architecture

Sensor Airport # Ops/Install

BUR Bob Hope 344 5

HPN Westchester County 461 12

NUQ San Jose Intl 504 8

STB St. Louis Intl 714 9

PDX Portland 722 13

FLL Ft. Lauderdale 830 14

OAK Oakland Intl 921 7

STC Seattle-Tacoma 950 19

LGB Long Beach 1107 6

EWR Newark Liberty Intl 1268 11

Sensor Airport # Ops/Install

JFK John F Kennedy Intl 1318 2

DTWA Detroit Metro 1319 17

LAXN Los Angeles 1388 3

DFW Dallas-Ft. Worth 1405 4

PHX Sky Harbor Intl 1476 18

DEN Denver Intl 1605 15

LAS McCarren Intl 1696 20

PHL Philadelphia Intl 1875 1

QXM O’Hare 2625 16

ATL Hartsfield Intl 2959 10

• 20 TRAMS Remote Sites• Denver is the only TRAMS Remote Site based at an enroute radar

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TRAMS Architecture (Remote Site Configuration)

NTP Time Server *

GPS Antenna

DataProcessor

SecureModem

PSTN(Public Switched Telephone

Network)

Channel A

Channel B

Surveillance

Comm-B

Ethernet - CAT 5e

RS-232

Surveillance

Comm-B

Ethernet - CAT 5e

SCAP Boundary

TRAMSCentral Site

OtherDevices

TDIC-B

Switch

TDIC-B

Ethernet - CAT 5e

NetworkHub

(Linux)

DataRecorder

Ethernet - CAT 5e

Mode SData Processors

(Linux)

Ground StationSurveillance Network

TRAMSRemote Site Network

UDP

SCAP Boundary

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TRAMS Data Collection and Processing• Remote Site Data Collection

– Equippage (transponder & TCAS types)

– For tracks declaring a RA and tracks not declaring an RA but would otherwise be reasonably expected to:

• The RA message

• Surveillance data

• 3rd party surveillance data

– Surveillance data for tracks exhibiting altimetry anomalies

• Remote Site Processing (Daily Summaries)

– Flight operations by equipage

– Environmental density by equipage & altitude bands

– Estimates of TA and RA rates for collision risk assessments

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TRAMS Architecture (Remote Site Configuration)

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TRAMS Architecture (Central Site Configuration)

GPS Antenna

PSTN(2 lines with provision for an additional line)

Ethernet – CAT 5e

RS-232

TRAMSCentral Processor

Secure Modems

1

2

3

SCAP Boundary

SCAP Boundary

RS-232

Line #1

Line #2

Expansion Line #3

NTP Time Server

USB

RS-232

ConverterRS-232

ToUSB

DVD / CD-ROMBurn Capability

Initial data analysis of TRAMS collected data

• Quick look – visualization of selected tracks

• Autoanalysis – isolation of “interesting” RA tracks

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TRAMS Data Flow

Mode-SChannel A

Mode-SChannel B

TRAMS Filtering and data Storage

Crypted Connection

Over thePublic

Switched Telephone Network

Lincoln Lab Data

Sanitization & Storage

Secure FTPOver

Commercial Internet

Remote Site

TRAMS Data Storage

WJHTCPC

Central Site

Manual Transfer Via Portable USB Media

Raw data files overwritten 45 days

after origination of file

Aut

oma

tica

lly

Data files transferred daily

Data files transferred weekly

Raw data files destroyed as soon as successful transfer to LL

Manually

Program Office TOPA Reports & Simulation Support Data

Reports provided on a minimum quarterly basis – data as needed

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TRAMS Deployment

• Three test sites.• PHL (April 2008)• JFK (July 2008)• LAX (November 2008)

• SCAP testing December 2008 – February 2009• TRAMS Deployment begins in Mar 08 at DFW.• New site installed about every 3 weeks thereafter.• Continuous data collection and analysis up to and including FY 2011.• Permanent data collection and daily summaries beyond FY 2011.

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Backup Slides

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A Brief History of TCAS (2)

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B1 Notional Systems Status Display (Central Site)

Pacific CentralMountain

EWR 0

HPN 0

FLL 0

JFK 41

PHL 0

ATL 0

STB 0

DTWA 0

DFW 0

QXM 0

PHL 15

ATL 0

PHL 15

ATL 0

PHX 0

DEN 0

FLL 0

JFK 41

PHL 15

ATL 0

BUR 0

NUQ 0

PDX 0

OAK 0

STC 0

LGB 0

LAXN 15

LAS 0

PHL 15

ATL 0

PHL 15

ATL 0

Eastern

FAA TCAS Resolution Advisory Monitoring System (TRAMS)

13 Nov 2008 17:30 GMT Modem 1

Modem 2Modem 3Modem 4UPS 90%

Site D/L RA CE VC N Site D/L RA CE VC N Site D/L RA CE VC N Site D/L RA CE VC N

Summary 12 Nov 2008 0000 – 2359 UTC

Sites Reporting: 2 Resolution Advisories: 56 Close Encounters: 30 Very Close Encounters: 12 Near Mid-Air Collisions: 1

Documents

TCAS Resolution Advisory Monitoring System (TRAMS) Carl B. Jezierski Airborne Team AJP-651