Safety Efficiency and Taskload in Air traffic Control

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Safety Efficiency and Taskload in Air traffic
Control

• Hildegard E. Winkler

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• Safety-Efficiency-Taskload Balance in ATC A Tool
  to Assess Sector Capacity from a human factor
  perspective
• (K. W. Kallus, P. Hoffmann, B. Ehgartner, Chr.
  Kuhn, A. Pichler, R. Schuen-Medwed)
• Safety-Efficiency-Taskload (SET) balance in air
  traffic control and their effects on
  workload.(Elisabeth Vormayr 2005)
• Safety-Efficiency-Taskload Balance
• Safety-Efficiency-Taskload A case study

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective

• Determination of sector capacities by fixed
  counts of maximum aircraft per hour in many
  European ACC
• Sector complexity (Mogford, Murphy and Gutman,
  1994)
• dynamic density (Laudemann et al.1998)
  determination of workload by traffic complexity
  and changing number of aircraft

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective

• Safety-Efficiency-Taskload Balance dynamic
  regulation of Taskload together with Safety and
  Efficiency
• Safety buffers and efficiency migth be affected
  by changes in dynamic density
• Allows to look at the problem from the controller
  side and take possible trade-off between
  taskload, efficiency and safety into account
• Safety regulation often violated to cope with
  increasing taskload

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective

• First step Interviews with supervisors
• Can the more or less implicitly given criteria of
  sector management be explicated by the use of
  cognitive interviews?
• In which of these factors and to what extent do
  different supervisors agree, and which factors
  are handled more or less individually?
• Can the factors of sector management be related
  to Mogford et als (1994) complexity factors or
  are the criteria different for the European
  Center at hand?
• Second step controllers perspective, interviews
  and
• workload measures

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective

• Method
• Study 1. Supervisors
• 13 supervisors of an European En-route-ACC,
• average Age 51,6 years
• Adapted Integrated Task Analysis nine topics
  (Controller Monitoring, Traffic Monitoring,
  Safety-Efficiency-Workload, decision making,
  conflict siutations, self-monitoring,
  safety-buffer)
• Study 2 Controllers
• 16 air traffic controller
• task observations with subsequent cognitive
  interviews including safety-efficiency-workload
  during 8 working periods

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective

• Results

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Safety-Efficiency-Taskload Balance in ATC A Tool
to Assess Sector Capacity from a human factor
perspective
Results Controller perspecitve
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Safety-Efficiency-Taskload (SET) balance in air
traffic control and their effects on
workload.(Elisabeth Vormayr 2005)

• Purpose was to find out how the variables safety,
• efficiency and taskload vary together and how a
• balance of the factors affects the Workload.
• METHOD
• Participants 12 male Air-traffic Controller,
  Tower (n7), ACC (n5), average age 37,5 years
• SET-programm, Simulation The ATC Interactive
  Radar Simulator ATC2K
• Handling of 27 simulations (safety, efficiency
  and taskload varied)
• safety (high vs. medium vs. low)
• efficiency (high vs. medium vs. low)
• taskload (high vs. medium vs. low)

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Safety-Efficiency-Taskload (SET) balance in air
traffic control and their effects on
workload.(Elisabeth Vormayr 2005)
UV Safety 1 low 2 medium 3 high
AV Safety Rating
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Safety-Efficiency-Taskload (SET) balance in air
traffic control and their effects on
workload.(Elisabeth Vormayr 2005)
AV Safety Rating
UV Safety 1 low 2 medium 3 high
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Safety Efficiency Taskload in air traffic Control

• Purpose was to find out, how the variables
  safety, efficiency
• and taskload vary in course of the time of the
  working
• periods.
• Method
• 31 participants (26 male, 5 female),
• average age 31,5years
• Units TWR, ACC, APP
• SET-Rating 5 min after start of the working
  period
• 65 min after start of the working period
• 125 min after start of the working period
• 5 min before break

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Safety Efficiency Taskload in Air traffic Control
Result Significant Timeeffect Taskload (?2
11.12 df5 p.049)
5 min after start of working period
5 min before break
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• Safety-Efficiency-Taskload
• A case-Study

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• Thank you for your attention!