Presentation to QAT TWG Fall 2004

1
ADS-B In-Trail ProceduresOverview of Research
Results
Presented to the ASAS TN2 Workshop September 2007
Kenneth M. Jones Crew Systems Aviation
Operations Branch NASA Langley Research
Center Hampton, Virginia 23681-2199 (757)
864-5013 E-mail Kenneth.M.Jones_at_nasa.gov
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Enhanced Oceanic Operations Objective and
Rationale

• Research Objective
• Develop methodologies, concepts, and procedures
  to reduce separation requirements for future air
  transportation systems using airborne ADS-B and
  Airborne Separation Assistance Systems (ASAS)
• Why airborne ADS-B and ASAS?
• Both are key components of NextGen and SESAR
  concepts of operation to accommodate much higher
  densities of air traffic
• Research and development of early ASAS
  applications will provide
• Insight into the nuances and details necessary to
  reduce separation requirements for the future
• Incentive for operators to voluntarily equip with
  transformational technologies and for
  manufacturers to develop suitable hardware and
  software
• Why Oceanic?
• Unique domain for conducting and obtaining
  valuable research data
• Can make dramatic improvements (reductions in
  separation) with ADS-B and ASAS without the need
  to develop completely new technologies
• These reductions can result in significant
  operational benefits
• Air traffic environment that is open to new
  technologies and procedures

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Enhanced Oceanic Operations Oceanic Challenges
and Incentives

• Efficient oceanic operations require flight level
  changes
• Climbs required for optimal performance as fuel
  is burned
• Altitude changes for favorable winds or to avoid
  turbulence

ASAS Enabled Climbs
Optimal
Sub-Optimal Cruise

• Current oceanic operations limit opportunities
  for flight level changes
• Many flights operate along the same routes at the
  same time
• Reduced surveillance performance (compared with
  radar) results in large separation minima for
  safe procedural separation
• Large separation minima often restrict aircraft
  from making desirable altitude changes
• Use of ASAS applications (including airborne
  surveillance and onboard automation) enable
  flight level changes which have operational
  benefits
• ADS-B ITP is an early phase of a multi-phase
  approach

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ADS-B In-Trail ProceduresFollowing Climb Example
FL360
FL350
FL340
Standard Separation
blue ADS-B transceiver and onboard decision
support system red ADS-B out minimum required

• Flights can be held at non-optimal altitudes due
  to traffic conflicts at intermediate altitudes
• ADS-B In-Trail Procedure application based on an
  approved ICAO procedure
• Controller separates aircraft based on
  information derived from cockpit sources and
  relayed by the flight crew
• Receipt of ADS-B data from surrounding aircraft
  use of a cockpit display and software provides
  data to qualify the aircraft for the maneuver
• No airborne monitoring during climb required
• Controller retains responsibility for separation
• The pilot requests, and the controller may
  approve, a flight level change based on
  information derived in the cockpit and the
  controllers awareness of the full traffic picture

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In Trail Procedure (ITP)
Enhanced Oceanic Operations Phase 2Standard
Climb vs ITP Climb
Current Separation
ALLOWED
BLOCKED
FL360
Desired Altitude
FL350
FL340
blue ADS-B transceiver and supporting display
system red ADS-B out minimum required white
no ADS-B requirements
Sequence of Events
Realize that a climb is desired
ITP speed/distance criteria Groundspeed
difference lt 20 kt and difference in range gt
15 nm or Groundspeed difference lt 30 kt and
difference in range gt 20 nm
Standard climb?
Unable
ITP following climb?
Valid
Request ITP following climb
Approved
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ADS-B In-Trail ProceduresResearch Activities

• Concept Development
• Concept of operations development for normal and
  non-normal operations
• RTCA/EUROCAE Requirements Focus Group (RFG)
  Airborne Traffic Situation Awareness ITP
  (ATSA-ITP) application description
• Establish a single, globally accepted, concept of
  operations (domain independent)
• Safety and Performance Analyses
• Safety and collision risk analysis using
  probabilistic methods and Monte Carlo simulation
  for the ITP
• RFG ATSA-ITP safety and performance assessment
  work
• ICAO Separation and Airspace Safety Panel (SASP)
• Concept Evaluation
• Use of TMX to evaluate ITP climb opportunities
  and efficiency gains
• Evaluation of ITP and cockpit decision support
  tools in NASA Langleys Air Traffic Operations
  Lab (ATOL) pilot perspective
• Evaluation of ITP operations controller
  perspective
• Operational flight evaluation of ITP

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ADS-B In-Trail ProceduresBatch Simulations

• Experiment Overview
• Evaluated ITP flight level change opportunities
• Simulation tool TMX
• Joint NLR/NASA medium fidelity batch simulator
• Includes pilot model, ATC model, CPDLC model, ITP
  procedure logic
• Focused on North ATlantic Organized Track
  Structure (NATOTS)
• Simulation of current day operations used as a
  baseline
• Distribution of traffic and track loading based
  on current day NATOTS data
• Varied traffic densities and ADS-B equipage
  levels
• Modeled ITP flight level changes as well as
  standard flight level changes that result from
  increased situation awareness
• Over 900 unique traffic flows simulated
• Preliminary Results
• Operational benefits are obtained with the use of
  an onboard ADS-B receiver and traffic display
• There are significant operational benefits from
  situation awareness

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ADS-B In-Trail ProceduresBatch Simulations
Difference between FMS Recommended Altitude and
Altitude Attained prior to Track Exit Moderately
Loaded Track, Medium Density, No ADS-B Equipage
Difference in feet
Altitude (feet)
Simulation Time (seconds)
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ADS-B In-Trail ProceduresBatch Simulations
Difference between FMS Recommended Altitude and
Altitude Attained prior to Track Exit Moderately
Loaded Track, Medium Density, 90/80 (ADS-B
Out/ADS-B In) Equipage
Difference in feet
Altitude (feet)
Simulation Time (seconds)
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ADS-B In-Trail ProceduresBatch Simulations
No ADS-B Equipage
90/80 Equipage

• At track exit
• No ADS-B equipage case 27 of aircraft are at
  FMS recommended altitude
• 90/80 equipage case 58 of aircraft are at FMS
  recommended altitude
• During the crossing
• No equipage 2 out of 52 aircraft climbed
• 90/80 equipage case 24 out of 52 aircraft made
  altitude changes with an average change of
  altitude of 1417 feet per aircraft

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ADS-B In-Trail ProceduresBatch Simulations
Variation of Fuel Savings Medium Density, 90/80
Equipage
Number of Aircraft
Fuel Savings (lbs)
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ADS-B In-Trail ProceduresConcept Validation
Study - Flight Crew Perspective

• ASAS applications require hardware, software and
  an appropriate crew interface
• Options for crew interface include primary field
  of view (e.g. PFD), forward field of view (e.g.
  EICAS or TCAS) or other secondary fields of view
  (e.g. EFB mounted on the side)
• Display Development
• Initial display designs conceptualized
• Survey questionnaires distributed to 1500 oceanic
  line pilots
• Design revised based on the 250 survey responses
  received

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ADS-B In-Trail ProceduresConcept Validation
Study - Flight Crew Perspective

• Research Objectives
• Assess the Validity of the ITP
• Assess Pilot Acceptability of the ITP
• Part-Task Human-In-The-Loop Experiment
• Conducted in ATOL September 2006
• 23 pilots over a 4 week period, 16 scenarios
  flown
• Participants were 777 and/or 747-400 pilots with
  current oceanic experience
• Developed prototype Flight Manual Bulletin and
  Electronic Flight Bag (EFB) interface

• NASA Air Traffic Operations Lab (ATOL)
• Medium-fidelity, part-task, air traffic
  simulation environment
• Designed for exploration of inter-aircraft,
  aircraft/airspace, and air/ground interactions
• Demo available

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ADS-B In-Trail ProceduresConcept Validation
Study - Flight Crew Perspective

• Results
• Procedure was rated as both valid and acceptable
• Workload was determined to be similar to standard
  level changes (no significant increase)
• Rating of 1 Minimal Operator Effort Rating of
  4 Moderately High Operator Effort
• Rating of 7 Maximum Operator Effort Rating
  of 10 Task Can Not Be Accomplished
• Pilots found the increased situation awareness
  provided by the display very useful
• Report to be published fall 2007

Mean Modified Cooper-Harper (MCH) workload
ratings associated with requested flight level
change maneuvers
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ADS-B In-Trail ProceduresConcept Validation
Study - Controller Perspective

• Research Objectives
• Assess whether ITP is valid from the perspective
  of an air traffic controller
• Assess whether ITP is acceptable to air traffic
  controllers
• Experiment conducted August 2007
• 12 controllers from two different procedural
  sectors
• Each controller dealt with multiple ITP scenarios
  in three 50 minute sessions
• Preliminary results
• Workload is no higher than current day operations
• Most controllers thought they would use it more
  than once per shift
• Recommendations for ITP phraseology were
  suggested
• Would prefer preformatted CPDLC messages to free
  text
• ITP could be acceptably applied using VHF voice

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ADS-B In-Trail ProceduresOperational Flight
Evaluation

• Goal of Operational Evaluation of ITP
• Evaluate the ITP concept in an operationally
  relevant environment
• Objectives of Operational Evaluation of ITP
• Assess operational performance and economic
  feasibility of ADS-B ITP
• Assess validity of simulation results
• Establish basis for global ADS-B ITP
  implementation and/or follow-on work
• Approach
• Conduct evaluation on revenue flights
• Support an evaluation in surveillance airspace
• Migrate to operational evaluation in
  non-surveillance airspace
• Results we will Obtain from an Operational
  Evaluation
• ADS-B data quality and reception ranges
• Frequency of use of ITP
• Real world aspects of the concept and
  implementation
• Aircraft system architecture investigation and
  evaluation
• Flight crew acceptance and usage of ADS-B In data
  for situation awareness
• Basis from which to develop future applications

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ADS-B In-Trail ProceduresInternational
Collaboration ICAO SASP

• ICAO Separation and Airspace Safety Panel
• ICAO authorization of a new separation standard
  required for flight in oceanic airspace
• Presentations given to SASP and Subgroups
• Developed and presented an ADS-B ITP collision
  risk analysis to the Mathematics Sub-Group
• Methodology and results well received
• Anticipating approval during late 2007
• Project Team 6 (Longitudinal Separation subgroup)
  adopted ITP as a part of their work program
• Australia presented a paper and proposed
  amendment to ICAO Doc. 4444 (PANS ATM) for ITP
• Anticipate approval in 2008
• SASP recognized this is as one of the first new
  separation standards that involves significant
  airborne ADS-B roles and responsibilities

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Summary

• ADS-B In-Trail Procedures
• Airborne ADS-B enabled climbs and descents
  through blocked flight levels
• More predictable and fuel-efficient operations in
  non-surveillance airspace
• Summary of Results
• Batch Results
• Operational benefits are obtained with the use of
  an onboard ADS-B receiver and traffic display
• Concept Validation Study Pilot Perspective
• Procedure was deemed to be acceptable and valid
• Workload was determined to be similar to standard
  level changes
• Concept Validation Study Controller Perspective
• Procedure was deemed to be acceptable and valid
• Workload was determined to be similar to standard
  level changes
• ICAO SASP
• Recognized ADS-B ITP as one of the first new
  separation standards that involves significant
  airborne ADS-B roles and responsibilities

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Back Up Slides
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ADS-B In-Trail Procedure (ITP) Flight Crew
Checklist
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ADS-B In-Trail ProceduresBatch Simulations
Difference between FMS Recommended Altitude and
Altitude Attained prior to Track Exit Busiest
Track, Medium Density, No ADS-B Equipage
24 of aircraft at FMS recommended altitude
Difference in feet
Altitude (feet)
Simulation Time (seconds)
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ADS-B In-Trail ProceduresBatch Simulations
Difference between FMS Recommended Altitude and
Altitude Attained prior to Track Exit Busiest
Track, Medium Density, 90/80 (ADS-B Out/ADS-B In)
Equipage
43 of aircraft at FMS recommended altitude
Difference in feet
Altitude (feet)
Simulation Time (seconds)
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ADS-B In-Trail ProceduresBatch Simulations
No ADS-B Equipage
90/80 Equipage

• At track exit
• No ADS-B equipage case 24 of aircraft are at
  FMS recommended altitude
• 90/80 equipage case 43 of aircraft are at FMS
  recommended altitude
• During the crossing
• No equipage 1 out of 83 aircraft climbed
• 90/80 equipage case 26 out of 83 aircraft made
  altitude changes with an average change of
  altitude of 1385 feet per aircraft