October 6, 2011 - RTCA

Special Committee 147
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RTCA Paper No. 010-12 /SC147-769
November 29, 2011
MINIMUM OPERATIONAL PERFORMANCE STANDARDS FOR TRAFFIC ALERT
AND COLLISION AVOIDANCE SYSTEMS AIRBORNE EQUIPMENT
The 73 rd meeting of SC-147 was held on October 6, 2011, at RTCA in Washington, DC. In
accordance with the Federal Advisory Committee Act, Mr. Roger Sultan, Federal Aviation
Administration (FAA) was the Designated Federal Representative for this meeting.
Bob Buley Co-Chairman, Aircraft Data Fusion
J. Stuart Searight Co-Chairman, Federal Aviation Administration (FAA
Technical Center)
Dan Tillotson Secretary, ARINC
Hal Moses RTCA
[Attachment 1 – Meeting Attendance]
Agenda Item 1. Opening Plenary Session
Co-Chairman Bob Buley welcomed the participants to the 73 rd meeting of Special Committee
147. Ken Carpenter noted that this was a joint meeting with EUROCAE Working Group 75 and
as Chairman of Working Group 75, he welcomed the participants to the 22 nd meeting of that
Working Group.
Co-Chairman Buley requested that everyone sign in and invited the meeting participants to
introduce themselves. The list of meeting participants is provided in Attachment 1.
Bob reviewed the planned agenda with the committee and outlined his planned schedule for the
meeting. The previously-distributed agenda was accepted with no amendments. He noted that
both working groups met at RTCA on 4 and 5 October.
Hal Moses provided an overview of the capabilities of the new RTCA facilities and discussed
administrative and emergency procedures for the new location.
Bob requested that meeting participants provide any comments on the minutes of the 72 nd
meeting. The minutes of the 72 nd meeting were approved as submitted.
Agenda Item 2. EUROCAE Working Group (WG)-75 Status Update
Ken Carpenter provided the committee with an update on current WG-75 activities. WG-75 has
met twice since the last SC-147 meeting. The next meeting of WG-75 is planned for 25-26
January 2011 in Cologne, Germany.
Ken noted that new Terms of Reference have been proposed to the EUROCAE Council to
include the following tasks and deliverables. This proposal has not yet been accepted.

1. Update Existing MOPS for TCAS II
2. Prepare MOPS for TCAS Hybrid Surveillance
3. Develop MOPS for Autoflight/TCAS Coupling
4. Develop guidance for traffic displays that support collision avoidance for aircraft not
carrying TCAS II
5. Define proposals to support the development of future collision avoidance systems
Ken noted that Working Group 75 had no plans to change the core TCAS II MOPS other than in
unison with SC-147, and that MOPS for TCAS II and Hybrid Surveillance are expected to be
identical to the RTCA MOPS.
The primary focus of the initial work on developing MOPS for the Autoflight/TCAS Coupling
will be in the areas of automatic guidance on RAs and altitude capture adaptation to reduce
occurrence of RAs. It is expected that a new subgroup will be established to complete this work
to ensure that appropriate expertise in autoflight systems is included in the work. Analyses have
shown that the collision risk will be reduced by a factor of two and the RA rate reduced by over
50% in European airspace with the implementation of the autoflight/TCAS coupling. Ken
expressed the desire from Working Group 75 to have the development of these MOPS be done in
concert with RTCA.
The SC-147 Co-Chairs outlined the process needed to have the efforts on MOPS development to
become a joint effort. Bob Buley expressed his desire that the appropriate expertise from SC-147
be involved in any joint work, regardless of which RTCA Special Committee eventually is tasked
with working with Working Group 75.
Working Group 75 has also been working on the compatibility of TCAS with ground safety nets
and the display of RA information to controllers. The Requirements Working Group (RWG)
spent some time during their meeting this week discussing the display of RA information to
controllers.
Ken introduced two presentations on the topic display of RA information to controllers:
� Yvonne Graner clarified DFS's motivation to perform significant research on this topic
following the Überlingen accident and an associated safety recommendation. She
outlined the DFS program for evaluating the use of this information, and the enabling
technology.
� Stan Drozdowski started by placing the display of RA information in the broader context
of Compatibility of Safety Nets. He provided an overview of ATS facilities where Mode
S RA downlink is already being used to display RA information to controllers although
there are no ICAO provisions for the operation of RA downlink. He concluded by
advocating a more holistic approach to further TCAS evolution.
Agenda Item 3. TCAS Program Office Activities
Neal Suchy provided an overview of the work being performed by the TCAS Program Office to
define potential next generation collision avoidance system. Work is also underway to
investigate the display of RA information to controllers. At the present time, the Program Office
does not support the display of information to controllers.
Agenda Item 3.a Monitoring Efforts/TRAMS/TOPA
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Wes Olson provided an overview of data collected and analyzed as part of the TCAS Operational
Assessment Program (TOPA). He noted that a majority of the data are being collected from
Mode S radars across the United States. There are 21 sites now operational and there are
currently over 150,000 RAs in the TOPA database. There has been little change in the findings
from the data since his report at the last SC-147 meeting.
Wes presented an overview of studies and analyses that have been completed on pilot response to
RAs; TCAS performance in level off encounters (with both 500 and 1000 ft separation from the
intruder); and RAs issued where an intruder could not be identified in the radar surveillance data.
Agenda Item 3.b Future Collision Avoidance System (CAS) Development Efforts
Neal Suchy provided an overview of the work being performed by the TCAS Program Office to
define potential next generation collision avoidance system. The Program Office’s efforts are
focused on three primary work packages.
1. Improve current surveillance performance to minimize TCAS utilization of the
1030/1090 MHz spectrum.
2. Develop threat logic that will be compatible with expected/planned changes in airspace
structure and operations. This threat logic is focused for use on aircraft that currently use
TCAS II systems.
3. Define surveillance requirements and concepts that will allow TCAS to use different
surveillance sources and use improved tracking algorithms.
Additional research is being conducted to evaluate requirements and concepts that could provide
a collision avoidance capability for other classes of airspace users.
Work is underway to conduct initial flight testing of the new threat logic in the 2013 time frame.
Agenda Item 4 AVS and Other FAA Activities
Agenda Item 4.a Certification and Flight Standard Activities
Roger Sultan provided an update on the TCAS-related activities that Flight Standards have been
working on since the last Plenary meeting.
The Flight Standards’ Outreach efforts have resulted in meetings and discussions with NetJets
and Boeing’s Training organization. The next efforts for the Outreach program are to conduct
briefings at NBAA Regional Forums and with ALPA.
A SAFO has been developed for Part 135 and Part 91k operators related to TCAS training and
guidance. This is in final review and is expected to be released shortly.
Flight Standards is also working on developing TCAS training material and has supported
verification of the implementation of the autopilot and flight director automated response systems
on the A350.
Roger introduced Wayne Gallo to the Committee. Wayne is a new member of the Flight
Standards Organization and will be representing Flight Standards in future SC-147 meetings.
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Agenda Item 4.b ASIAS/CAST/CAS Steering Committee
There were no discussions under this agenda item.
Agenda Item 5. Working Group Status Reports
Agenda Item 5.a Requirements Working Group (RWG)
Andy Zeitlin provided a summary of the RWG’s work since the last Plenary meeting. The main
focus is preparing a report on future collision avoidance systems and work on that report has been
completed. Andy’s report provided an overview of the contents and recommendations from the
report. The report identifies both near-term and long-term improvements that could be
incorporated into the collision avoidance logic.
The contents of the report were reviewed this week by the RWG and the RWG is in agreement
with the current version of the report. Following the completion of a few editorial cleanup
changes, the report will be ready for distribution to the Committee for review and comment.
To support the delivery of the report to the Program Management Committee (PMC) in
December 2011, the following distribution and review schedule was agreed to during the
meeting.
Initial Distribution October 19, 2011
Comments Due Back to Andy November 7, 2011
Telecon/Webex to Review Comments November 9, 2011
Deliver to PMC November 30, 2011
Agenda Item 5.b Surveillance Working Group (SWG)
Ruy Brandao provided a status report on the SWG’s work. Since the last SC-147 meeting, work
has continued to develop and evaluate means of reducing the TCAS utilization of the 1090 MHz
frequency. A simulation model that was previously developed was updated to incorporate all six
specific change proposals and testing was done with all of the various proposals. Simulations
show that Changes to DO-300 would result in 1090 MHz utilization reduction of 60% to 85%
when all simulated TCAS II equipped aircraft have these changes implemented. Additional
change proposals have been defined which would further reduce the contributions of on-ground
TCAS to 1090 MHz utilization. Evaluation of the benefits of these changes is expected to be
complete by the end of the year. Safety studies do not show any degradation in risk ratio when
these changes are implemented.
The SWG recommended that the Terms of Reference be amended to allow incorporation of these
changes in the MOPS. The SWG will continue work on the change proposals under the
assumption that the Terms of Reference will be updated. This may result in changes to DO-
185B, DO-300, or both.
The SWG also proposed allowing TAs to be issued based solely on ADS B data (for hybrid
surveillance equipped aircraft) if the intruder was not already being interrogated and then
switching to active interrogations immediately after the TA was issued. The Committee agreed
with this proposal.
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The SWG also sought the Committee’s input on a change proposal to limit, in surveillance, the
tracking of aircraft within 3000 feet above the airport surface when TCAS is operated while the
own aircraft is on the ground. There were no objections to this proposal and no concerns were
expressed with such an implementation.
The Co-Chairs agreed to caucus on how to handle proposing these change proposals to the PMC.
The Co-Chairs will distribute the results of their discussions, along with their recommendations,
to the Committee in the same time frame that the RWG report is distributed.
Agenda Item 6 Consideration of Final Proposed Changes to SC-147 Terms of Reference
There were no specific discussions conducted under this agenda item.
Agenda Item 7 Other Business
Agenda Item 7.a Traffic Situational Awareness with Alerts (TSAA) Status
Dave Gray presented an overview of the of the SC-186 work to develop requirements and
standards for TSAA. The Committee provided comments and feedback on the concept of TSAA
and its operational use with the intent of ensuring that TSAA did not degrade the performance
and safety provided by TCAS II.
Agenda Item 8 Action Items
There were no discussions under this agenda item.
Agenda Item 9 Closing Session
Agenda Item 9.a. Date and Time of Next Meeting
All presentations from this meeting are available on the RTCA/SC-147 website or from RTCA
upon request.
The next meeting of the Committee will be scheduled following the RTCA PMC meeting
scheduled for December. The Co-Chairs will schedule this meeting once further guidance on the
Committee’s proposals and recommendations is received from the PMC.
Certified as a true and accurate summary of the meeting.
Co-Chairmen
-S- -S-
Mr. Robert Buley Mr. Stuart Searight
Aircraft Data Fusion FAA
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Attachment 1
Meeting Attendance for SC-147 Plenary on October 6, 2011
Name Organization E-mail
Thierry Arino Egis Avia thierry.arino@egis.fr
Christian Aveneau DSNA aveneau@cena.fr
Larry Bachman Regulus Group LLC lbachman@regulus-group.com
Ben Bakker EUROCONTROL ben.bakker@eurocontrol.int
John Banzhaf USAF john.banzhaf.ctr@hanscom.af.mil
Carl Bayh BAE Systems raymond.bayh@baesystems.com
Walter Bender JHU/APL walter.r.bender@jhuapl.edu
Ruy Brandao Honeywell International ruyjr.brandao@honeywell.com
Robert Buley Aircraft Data Fusion bobbuley@aircraftdf.com
Joslin Carino FAA joslin.carino@faa.gov
Ken Carpenter QinetiQ ken@kencarpenter.co.uk
Michael Castle Aurora Sciences LLC mcastle@aurorasciences.com
Mark Cato Air Line Pilots Association catom@alpa.org
Kathryn Ciaramella FAA kathryn.cairamella@faa.gov
Robert Clarke Alion Science and Technology rclarke@alionscience.com
Jonathan Dahlgren Honeywell jonathan.dahlgren@honeywell.com
Stanislaw Drozdowski EUROCONTROL stanislaw.drozdowski@eurocontrol.int
Ann Drumm MIT Lincoln Laboratory drum@ll.mit.edu
Tomas Elder MIT Lincoln Laboratory tomas.elder@ll.mit.edu
John Fisher FAA john.d.fisher@faa.gov
Gaston Formisano Rockwell Collins cgformis@rockwellcollins.com
Wayne Gallo FAA wayne.gallo@faa.gov
Edward Glowacki Titan Corporation edward.ctr.glowacki@faa.gov
Jose Goday ARINC jgoday@arinc.com
Yvonne Graner DFS yvonne.graner@dfs.de
David Gray FAA david.e.gray@faa.gov
Carl Jezierski FAA carl.jezierski@faa.gov
Jessica Holland MIT Lincoln Laboratory jessica.holland@ll.mit.edu
Al Mattox ARINC amattox@arinc.com
Ralph Mintel FAA ralph.mintel@faa.gov
Matt Modderno FAA Matt.modderno@faa.gov
Harold Moses RTCA hmoses@rtca.org
Wesley Olson MIT Lincoln Laboratory wes.olson@ll.mit.edu
Thomas Pagano FAA thomas.pagano@faa.gov
Adam Panken MIT Lincoln Laboratory adam.panken@ll.mit.edu
Chuck Rose MIT Lincoln Laboratory c.rose@ll.mit.edu
Stacey Rowlan L-3 Communications stacey.rowlan@L-3com.com
Stuart Searight FAA Technical Center stuart.searight@faa.gov
Joshua Silbermann The Johns Hopkins University joshua.silberman@jhuapl.edu
Charles Sloane FAA charles.sloane@faa.gov
David Spencer MIT Lincoln Laboratory dspencer@ll.mit.edu
Neal Suchy FAA neal.suchy@faa.gov
Roger Sultan FAA roger.sultan@faa.gov
William Thedford U.S. Air Force aacas-llc@comcast.net
Dan Tillotson ARINC dtillots@arinc.com
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Name Organization E-mail
Thomas Troast Regulas Group tetroast@regulas-group.com
Jessie Turner Boeing jessie.turner@boeing.com
Ethan Walters Aurora Sciences ewalters@aurorasciences.com
Andrew Zeitlin MITRE Corporation/CAASD azeitlin@mitre.org
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