Human Factors/Cognitive Engineering Principal Investigators: Nadine B. Sarter Christopher D. Wickens Graduate Students: Beth Kelly Scott McCray 5-1
SMART ICING SYSTEMS Research Organization Core Technologies Aerodynamics and Propulsion Flight Mechanics Controls and Sensor Integration Human Factors Aircraft Icing Technology IMS Functions Characterize Icing Effects Operate and Monitor IPS Envelope Protection Adaptive Control Flight Simulation Demonstration Safety and Economics Trade Study 5-2
Human Factors/Cognitive Engineering Goal: Improve the safety of aircraft in icing conditions. Develop smart systems to improve ice tolerance. Objective: Design human-centered interfaces that a) inform pilots about presence and performance effects of icing conditions b) communicate IMS status/activities/limitations to crew in timely and effective manner c) provide pilots with advisories for handling inflight icing encounters safely Approach: Identify pilots information requirements (survey/focus groups/incident and accident analysis) Design use-centered cockpit interfaces Evaluate effectiveness and robustness of different implementations in simulator 5-3
Human Factors/Cognitive Engineering Ice Management System Functions - Information Automation (Presentation/management of data concerning onset/development of icing conditions and IMS status/activities) - Advisory System (e.g., support pilots in responding to different types of handling events in timely and effective manner) - Control Automation (e.g., limit/alter pilot input for envelope protection, flight control adaptation) 5-4
Smart Icing System Research Scott McCray, Beth Kelly, and Nadine Sarter Beth Kelly, Scott McCray, and Nadine Sarter Scott McCray, Nadine Sarter Beth Kelly, Nadine Sarter Characterize Icing Effects Large-Scale Pilot Survey Operate and Monitor IPS Pilot Survey and Focus Groups Incident/Accident Process Tracing Analysis Information Requirements and Representation for Effective Pilot-Automation Communication and Coordination Envelope Protection Adaptive Control Command vs. Status Display Simulation Study THE HUMAN FACTORS GROUP Flight Simulation Demonstration 5-5
Information Requirements Pilots Information Requirements Survey of Regional Carriers Focus Groups with Regional Pilots Analysis of Icing-Related Incident and Accident Reports 5-6
Information Requirements Pilot Survey (in collaboration with ALPA) Sent to 6,400 pilots from 9 regional carriers Ratings and explanation of importance of information on 3 areas: - Characteristics of icing - Aircraft configuration and performance - IMS/IPS status/activities 5-7
Information Requirements Ice Characteristics Shape of Ice Accretion 3 Critical information - needed at all times Rating scale: 2 Sometimes important (when? why?- please comment) 1 Nice to have 0 Not needed (during suspected or actual icing conditions) Information Type Rating Your Comments Location of Ice Accretion Rate of Ice Accretion Amount of Ice Accretion Type of Icing (clear vs. rime) 5-8
Information Requirements Open-ended questions about: - company policies/procedures - operational experiences - training - monitoring behavior - frequency of encounters - suggestions for IMS functions/design 5-9
Information Requirements Pilot Survey: Considered critical at all times : - Location/Rate/Amount of Ice Accretion - OAT - Stall Margin/Angle of Attack - IMS/IPS status - Current IMS actions - Reliability of IMS Sensors 5-10
Information Requirements Underestimate importance of: Shape of Ice Accretion Reliability of and Reasoning Behind IMS Recommendations Implications for Training Limited Usefulness of Subjective Data 5-11
Information Requirements Process-Tracing Analysis of Incidents and Accidents Time Who Cue Modality Approach Interpretation Action Selection 15:20 Captain Ice accretion behind boots Visual Knowledgedriven Is this just like Roselawn? Keeps monitoring 15:25 Both PIlots Buffet Haptic Data-driven Ice buildup on wings Activate level 3 deice equipment 5-12
Information Requirements Data-Driven Knowledge-Driven Expectations /Questions verify/ answer ICING and Sampling of Environment direct Attention Allocation Nikolic and Sarter, 1997 [modified from Neisser (1976)] 5-13
Information Requirements GOAL Identify What Cues Are (Not) Successful In Capturing Attention Identify Problems with Cue/Pattern Interpretation Identify Mismatches Between Cue/Diagnosis/Action Selection.to inform the design of IMS displays that provide information in timely, effective, and meaningful manner 5-14
Implementation of Advisory Functions Simulator Study To Examine the Effectiveness of Command vs. Status Displays - 30 instructor pilots from Institute of Aviation - 3 conditions: - baseline - status display - command display - medium fidelity simulation of twin-engine aircraft - simulates icing cues 5-15
Implementation of Advisory Functions Wing versus Tail Icing Symptoms - increase in descent rate - airframe buffet - forward pull on yoke - increase in descent rate - yoke buffet Response - add power - maintain/extend flaps - reduce pitch - reduce power - retract flaps - increase pitch 5-16
Implementation of Advisory Functions 3 experimental groups: - no aid (except for probe) - status display - command display Within-subjects variables: - accuracy of system-provided information and recommendation - familiarity of condition (wing vs. tail) - manual vs. autopilot control the crew is often unaware of a developing instability or control degradation until the autopilot gives up and hands the pilot a very serious and rapidly deteriorating problem. (Green, 1998) 5-17
Implementation of Advisory Functions Dependent variables: - RT to probe onset - speed/nature of pilots response - stall? - ability to recover - timing of autopilot disconnect - tracking performance - subjective comments on displays 5-18
Implementation of Advisory Functions The Status Display (Wing Icing) 5-19
Implementation of Advisory Functions Command Display - Provides recommendations for pitch, power, and flap settings - Bottom of stall speed arc will move to show increase in stall speed due to ice formation - Information is integrated with existing displays to reduce information access costs 5-20
Implementation of Advisory Functions The Command Displays (Wing Icing) 5-21
Implementation of Advisory Functions Preliminary Findings - baseline condition reaches stall more frequently but also: - baseline notices glideslope failure more often - all groups are considerably affected by inaccurate information from the system (in particular, the status display group) - autopilot is masking problems and thus creates problems with recovery once disengaged 5-22
Human Factors Waterfall Chart Federal Fiscal Year 98 99 00 01 02 03 Information Requirements Process-Tracing Analyses Command vs. Status Displays Trend Displays/Task+System Integration/ Envelope Protection and Flight Control Adaptation Implementation Evaluation/Refinement of Integrated IMS Cockpit Interface 23 5-23
Summary and Conclusions - Increased need for human-machine communication and coordination due to increasing levels of system complexity and autonomy - Need for use-centered interface that takes into consideration human information-processing abilities, strategies, and limitations as well as task context HUMAN(S) Cognitive Triad MACHINE(S) (TASK) CONTEXT 5-24
Future Research i Development of Trend Displays To Support Monitoring, Decision-Making, and Action Selection i Integration with other Pilot Tasks and Cockpit Systems (e.g., TCAS; high visual demands during approach) i Implementation of/interfaces Related To Envelope Protection and Flight Control Adaptation 5-25