Self-Separation from the Air and Ground Perspective

1
Self-Separation from the Air and Ground
Perspective

• Margaret-Anne Mackintosh, Melisa Dunbar, Sandra
  Lozito, Patricia Cashion, Alison McGann, Victoria
  Dulchinos NASA Ames Research Center
  mmackintosh_at_mail.arc.nasa.gov
• Rob Ruigrok, Jacco Hoekstra, Ronald Van Gent
  National Aerospace Laboratory, NLR ruigrok_at_nlr.nl

2
Introduction

• NLR Free Flight with Airborne Separation
  Assurance
• Air perspective
• NASA Ames Air-Ground Integration Study
• Air and Ground perspective

3
NLR Human-In-The-Loop Study Introduction

• NLR Free Flight with Airborne Separation
  Assurance
• Free Flight Concept Development
• Traffic Experiment Manager off-line simulations
• Find a suitable base-line concept
• Free Flight Safety Analysis
• Traffic Organization and Perturbation AnalyZer
  (TOPAZ)
• Predict critical non-nominal situations
• Free Flight Human-in-the-Loop Simulation
  Experiment
• NLRs Research Flight Simulator
• Human Factors Issues
• Validation of concept with Human-in-the-Loop

4
NLR Human-In-The-Loop Study Methods

• Probe the limits
• No Air Traffic Control
• Air crew responsible for traffic separation
• All aircraft in scenario fully equipped
• Automatic Dependent Surveillance - Broadcast
  (ADS-B)
• Conflict Detection
• Conflict Resolution
• Cockpit Display of Traffic Information (CDTI)
• Cruise flight only
• Direct routing
• Optimal cruise altitude

5
NLR Human-In-The-Loop Study Scenarios

• 8 crews, 18 runs per crew, 20 minutes per run
• current airline pilots
• 2 days including half a day of training

• Traffic Densities Single, Double, Triple
• Level of Automation Manual, Execute Combined,
  Execute
  Separate
• Non-Nominal Other aircraft failures/events,
  Own aircraft
  failures/events,
  Delay time increased

6
NLR Human-In-The-Loop Study Concept

• Modified Voltage Potential
• Characteristics
• Fail safe
• Co-operative
• More options
• Clear to pilot
• Communication not required

Similar in vertical plane
7
NLR Human-In-The-Loop Study Flight Crew Interface

• Navigation Display
• Traffic Symbology
• Conflict Detection
• Resolution Advisories
• Vertical Navigation Display
• Extra EFIS Control Panel functionality
• Modifications to Autopilot
• Execute Combined
• Execute Separate
• Aural alerts

8
NLR Human-In-The-Loop StudySubjective Results
Acceptability

• Distribution of responses as a function of
  the three densities, across all sessions,
  across all subject pilots
• Acceptability 91.5 (single), 83.0
  (double), 78.7 (triple)

9
NLR Human-In-The-Loop StudySubjective Results
Safety

• Distribution of responses as a function of
  the three densities, across all sessions,
  across all subject pilots
• Safety 88.3 (single), 75.5 (double),
  71.3 (triple)

10
NLR Human-In-The-Loop StudySubjective Results
Workload

• Rating Scale of Mental Effort (RSME)
• Rating less than 40 (costing some effort)
  over all densities
• Results similar to cruise phase results in
  current ATC scenarios

11
NLR Human-In-The-Loop Study Objective Results
EPOG

• Eye-Point-Of-Gaze measurements
• Pilot Flying and Pilot-Not-Flying
• Percentages of the total fixation duration,
  averaged over the Pilot Flying and
  Pilot-Non-Flying, across all sessions

• Primary Flight Display 8.1
• Lateral Navigation Display 48.9
• Vertical Navigation Display 7.6

12
NLR Human-In-The-Loop Study Objective Results
Maneuvers

• Distribution of maneuvers as a function of
  the three different modes, across all
  sessions, across all subject pilots
• Maneuvers Heading 71.0 Speed 40.3
  Altitude 48.7

13
NASA Air-Ground Integration Study Methods

• Boeing 747-400 simulator and Airspace Operations
  Lab
• Flight deck and controller perspectives
• 8 DIA enroute scenarios (20 minutes in duration)
• 10 flight crews/10 controllers
• New display features on flight deck
• Airborne alert logic (no ground conflict probe)
• Controller tools similar to those at DIA
• Controller monitoring more than controlling
• Run in March/April 1998

14
Background/Research Goal

• Background
• RTCA Free Flight document recommends aircraft
  self-separation in particular situations (e.g.,
  enroute environment)
• Requires new conceptual airspace that includes
  human performance parameters
• Aircraft self-separation will require a shift in
  roles and responsibilities between the users on
  the ground and in the air
• Research Goal
• To conduct early simulations examining flight
  deck human performance parameters

15
NASA Air-Ground Integration Study Scenarios

• Traffic on flight deck (ADS-B range 120 nms)
• Traffic on controllers radar display (DIA Sector
  9)
• Representation of high v. low density/clutter
• High 16-17 aircraft, low 6-8 aircraft
• Blocker aircraft preventing most common
  resolution
• Conflict event types high and low density
• Obtuse angle
• Acute angle
• Right angle
• Almost intruder

16
NASA Air-Ground Integration StudyDisplays

• Flight deck display
• No early alert indication (prior to alert zone
  transgression)
• Alert zone transgression display features
• Temporal predictors and call signs selectable
• Controller Display
• Similar features as those currently in DIA (e.g.,
  vector lines, J rings)
• Some features from CTAS, but no enhanced functions

17
NASA Air-Ground Integration Study Flight Crew
Results

• Density and detection time
• Flight crews took longer to detect conflicts in
  high density compared to low density scenarios
• Conflict Angles and detection time
• No differences in detection times between the
  conflict angles
• Ratings of conflict detection and time pressure
• Significant increase in reported workload and
  time pressure as a function of traffic density
• No differences for almost intruder for detection
  times

18
NASA Air-Ground Integration StudyPilot Detection
Times
19
NASA Air-Ground Integration StudyController
Results

• Effects of traffic density and conflict angle on
  detection times
• Interaction between density and angle
• Longer detection time in obtuse angle high
  density v. obtuse angle low density
• Shorter detection time in acute angle high
  density v. right angle and obtuse angle high
  density
• Ratings of workload and task complexity
• Significant increase in ratings of workload and
  complexity as a function of density
• No differences for almost intruder detection times

20
NASA Air-Ground Integration StudyController
Detection Times
21
General Summary

• Consistent Findings across Studies
• Impact for increasing density
• density may be exacerbated by other factors
• existence of abnormal situations (e.g. weather)
  may limit self-separation
• Losses of minimum separation
• flight crews try to minimize separation between
  aircraft while maintaining legal separation
• controllers wanted larger separation than the
  flight crews maintained (NASA study)

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General Summary

• Unique Findings
• Pilots fixate on CDTI 60 of the time and PFD 10
  of the time (NLR study)
• Pilots reported spending too much time on the
  CDTI (NASA study)
• Performance parameter usage
• Heading was most common parameter used (NLR
  study)
• similar to previous NASA studies
• Altitude was most common parameter used (NASA
  study)
• inclusion of the blocker aircraft in most
  common lateral escape path

23
General Summary

• Unique Findings (NASA)
• Conflict angles affect controllers and flight
  crews
• controller conflict detect times
• flight crew timing and type of maneuver
• Density and conflict angle may interact
• Frequent air-to-air communication

24
Future Research Issues

• Addition of abnormal situations for workload
  realism (e.g., weather, winds, SUA, passenger
  problems)
• Assessment of data link for communications to
  help frequency congestion
• Simulation including representation of additional
  carriers and dispatch
• Information requirements assessment for shared
  situation awareness