Deneen Harris

Predicting pilot error: testing a new methodology and a multi-methods and analysts approach.

The Human Error Template (HET) is a recently developed methodology for predicting design-induced pilot error. This article describes a validation study undertaken to compare the performance of HET against three contemporary Human Error Identification (HEI) approaches when used to predict pilot errors for an approach and landing task and also to compare analyst error predictions to an approach to enhancing error prediction sensitivity: the multiple analysts and methods approach, whereby multiple analyst predictions using a range of HEI techniques are pooled. The findings indicate that, of the four methodologies used in isolation, analysts using the HET methodology offered the most accurate error predictions, and also that the multiple analysts and methods approach was more successful overall in terms of error prediction sensitivity than the three other methods but not the HET approach. The results suggest that when predicting design-induced error, it is appropriate to use a toolkit of different HEI approaches and multiple analysts in order to heighten error prediction sensitivity.

Risk Perception and Risk-Taking Behavior of Construction Site Dumper Drivers

In the UK construction site dumpers cause more serious accidents than any other type of construction plant. Previous research has indicated that driver behavior plays a pivotal role in the vast majority of these accidents. This study used a paired comparison technique to explore dumper drivers’ and subject matter experts’ (SMEs’) risk perception and its relationship to risk-taking behavior. It was found that driver risk perception significantly differed from measures of “objective risk”, derived from accident data and also from SMEs ‘ risk perception. Furthermore, drivers still engaged in undertaking perceived high risk behaviors. The results suggest that driver risk perception was linked to the “perceived dread” of an accident, rather than its likelihood and that risk-taking behavior was often driven by situational factors, such as site safety rules or the behavior of other personnel on the site, together with an overarching culture that prioritizes production over safety.

A psychophysiological approach to the assessment of work underload

The findings of a laboratory investigation of the relationship between the subjective and physiological components of work underload are reported. The subjective component is described in terms of the subjective work underload checklist, mental effort, and cognitive arousal. The physiological component is defined in terms of heart rate and heart rate variability. Evidence for an increase in work underload with a decrease in heart rate is provided. The relevance of this research to the aerospace environment is discussed and the need to investigate the behavioural component of work underload emphasized.

An extension of the Human Factors Analysis and Classification System for use in open systems

The Human Factors Analysis and Classification System (HFACS), based upon Reasons model of human error in an organisational context, is currently the most widely used human factors accident analysis framework. However, it has been criticised for merely categorising accident data rather than analysing it. Previous research has established statistical associations between the levels and categories within HFACS but has not specified a mechanism by which one category influences subsequent behaviour. This paper extends the approach in two ways. Using the categories of control flaws derived from Levesons Systems–Theoretical Accident Model and Processes (STAMP) approach, it describes the mechanisms by which categories within HFACS are associated with other categories lower in the organisational hierarchy. It also provides a mechanism by which active failures can promulgate across organisations. The revised methodology HFACS-STAMP is illustrated using the case study of the Uberlingen mid-air collision on 1 July 2002.

Cockpit design and cross-cultural issues underlying failures in crew resource management.

High power-distance has been implicated in many aircraft accidents involving Southeast Asian carriers where crew resource management (CRM) has been identified as a root cause. However, this commentary argues that the design of modern flight decks and their standard operating procedures have an inherent Western (low power-distance) bias within them which exacerbates these CRM issues.

Ripples in a pond: an open system model of the evolution of safety culture.

The development of an effective safety culture is essential to promote safe operations. Previous studies haveeither identified the characteristics of effective safety culture analytically, inferring them from signs and symbolsderived from working practices, or have restricted the study of the development of safety culture to workerswithin an organisation. This paper describes a large-scale survey-based study in which the factors influencingthe evolution of safety culture are identified empirically and, drawing upon open systems theory, are alsoextended beyond the bounds of the organisation. Three major determinants of safety culture are identified:safety concerns, influences and actions. Sub-components within each of these categories are also identified andthe relationship between them is hypothesised.

The development of a multidimensional scale to evaluate motor vehicle dynamic qualities.

Advances in motor vehicle engineering will allow greater refinement of the dynamic qualities of passenger cars in the near future. This paper describes the development and initial validation of a reliable and valid multidimensional scale to assess these parameters based upon a technique previously developed to evaluate aircraft handling qualities. The scaling methodology developed emphasizes the interaction between the vehicles dynamic behaviour and the category of vehicle (e.g. sports car, executive saloon). This three-part study describes the initial extraction and the subsequent verification of the scale dimensions from an analysis of the opinions of circa 500 drivers, followed by an evaluation of the sensitivity and diagnosticity of the scale to distinguish between the road behaviour exhibited by vehicle types. The results suggest that the scale shows both content and construct validity, being able to distinguish both between broad categories of vehicle and different models of vehicle within a particular category in a consistent and meaningful manner.

Combining control input with flight path data to evaluate pilot performance in transport aircraft

INTRODUCTION When deriving an objective assessment of piloting performance from flight data records, it is common to employ metrics which purely evaluate errors in flight path parameters. The adequacy of pilot performance is evaluated from the flight path of the aircraft. However, in large jet transport aircraft these measures may be insensitive and require supplementing with frequency-based measures of control input parameters. METHOD Flight path and control input data were collected from pilots undertaking a jet transport aircraft conversion course during a series of symmetric and asymmetric approaches in a flight simulator. The flight path data were analyzed for deviations around the optimum flight path while flying an instrument landing approach. Manipulation of the flight controls was subject to analysis using a series of power spectral density measures. RESULTS The flight path metrics showed no significant differences in performance between the symmetric and asymmetric approaches. However, control input frequency domain measures revealed that the pilots employed highly different control strategies in the pitch and yaw axes. CONCLUSION The results demonstrate that to evaluate pilot performance fully in large aircraft, it is necessary to employ performance metrics targeted at both the outer control loop (flight path) and the inner control loop (flight control) parameters in parallel, evaluating both the product and process of a pilots performance.