Aviation Safety Locus of Control scale

Abstract

The Aviation Safety Locus of Control scale (ASLOC) is a domain-specific psychometric instrument designed to measure aviators’ generalized expectancies regarding the locus of control over operational flight safety, mishaps, incidents, and accidents. Developed by psychometrician and aviation psychologist David R. Hunter in 2002, the instrument adapts the foundational social learning theory formulated by Julian B. Rotter and subsequent occupational safety frameworks to the complex cognitive and situational demands of aviation. The ASLOC captures the extent to which pilots attribute flight safety outcomes either to their own skill, vigilance, risk management, and regulatory compliance (internal locus of control) or to external, uncontrollable circumstances such as mechanical malfunctions, meteorological extremes, regulatory oversight failures, fate, or chance (external locus of control).

The standard instrument comprises 20 balanced Likert-type items scored across two primary dimensions: the Internal Safety Locus of Control subscale and the External Safety Locus of Control subscale. Each subscale is evaluated using 10 declarative statements rated on a 5-point continuum ranging from Strongly Disagree (1) to Strongly Agree (5). Psychometric evaluation across diverse international samples—including commercial, military, and general aviation pilots—demonstrates adequate internal consistency, with initial derivation research reporting Cronbach’s alpha coefficients of 0.69 for the Internal subscale and 0.63 for the External subscale among a cohort of 477 aviators. Subsequent cross-cultural validations, notably in military and civil aviation populations, confirm a robust two-factor orthogonal or mildly correlated structure. The ASLOC exhibits meaningful convergent and predictive validity, correlating systematically with self-reported hazardous flight events, pilot risk-taking behaviors, compliance with standard operating procedures (SOPs), and attitudes toward crew resource management (CRM). Consequently, the scale serves as a vital diagnostic and predictive tool for human factors researchers, flight training academies, and safety management systems seeking to enhance aeronautical decision-making and mitigate human error.

Keywords

Aviation Safety Locus of Control, ASLOC, aviation psychology, pilot decision making, human factors, safety locus of control, flight safety, risk perception, crew resource management, aeronautical decision-making, internal locus of control, external locus of control

Authors

The Aviation Safety Locus of Control scale was conceptualized, constructed, and empirically evaluated by David R. Hunter, Ph.D.

• Primary Author: David R. Hunter, Ph.D.
• Institutional Affiliation: Formerly with the Federal Aviation Administration (FAA) Civil Aerospace Medical Institute (CAMI) and the Office of Aerospace Medicine, Washington, D.C., United States.
• Research Profile: Dr. Hunter is an internationally recognized specialist in cognitive pilot selection, human factors engineering, risk management, and aeronautical decision-making. He has authored foundational monographs for the United States Air Force Armstrong Laboratory and the FAA on pilot risk assessment, hazardous attitudes, and flight performance prediction.
• Subsequent Key Investigators: The scale has undergone extensive cross-cultural adaptation and operational validation by researchers including C. Joseph and A. Ganesh (Institute of Aerospace Medicine, Indian Air Force, Bangalore, India), who evaluated the instrument’s operational utility among military fast-jet and transport aviators.

Purpose

The primary purpose of the Aviation Safety Locus of Control scale is to operationalize and quantify the specific attributional styles that aviators hold concerning the causes of aviation accidents, operational incidents, and flight-deck safety. Human error is universally recognized within human factors literature as a contributing causal factor in roughly 70% to 80% of all aviation mishaps. Understanding the cognitive antecedents of unsafe acts, deviation from standard procedures, and poor risk assessment is critical for structural intervention. General generalized expectancy scales, such as Rotter’s Internal-External (I-E) scale, have historically yielded weak to moderate effect sizes when predicting highly specialized technical behaviors. The ASLOC addresses this domain-specificity deficit by anchoring locus of control constructs directly within aeronautical operating contexts.

From an applied perspective, the ASLOC functions across several key domains:

• Ab Initio Pilot Selection and Assessment: While rarely utilized as an exclusionary barrier in isolation, the ASLOC provides flight training organizations and airline cadet selection boards with critical baseline data regarding a candidate’s attributional tendencies. Candidates with extreme external orientations may exhibit diminished receptivity to debriefing, flight instruction, and corrective feedback.
• Flight Safety Auditing and Safety Management Systems (SMS): Commercial operators and military squadrons implement the ASLOC to assess organizational safety culture and the prevailing psychological climate within pilot cohorts. Shifts toward an external locus of control across a flight wing often indicate systemic operational cynicism, organizational fatigue, or perceived procedural injustice.
• Targeted Crew Resource Management (CRM) Refinement: Instructors utilize individual and aggregated ASLOC scores to tailor CRM modules. Pilots with high external locus of control can be trained to recognize the extent to which their personal vigilance and assertiveness alter operational outcomes, countering the dangerous hazardous attitudes identified by the FAA, such as resignation (“What’s the use?”) and invulnerability (“It won’t happen to me”).
• Post-Incident Remediation and Counseling: Following an operational deviation, runway incursion, or unstable approach incident, aviation psychologists use the scale to assess whether the pilot displays accountability and an internal motivation to modify flight practices, or conversely attributes the failure exclusively to air traffic control (ATC), weather phenomena, or aircraft systems.

Psychological Construct

The construct assessed by the ASLOC is the domain-specific Safety Locus of Control applied to aeronautics. Safety locus of control refers to an individual’s generalized belief system regarding the degree of causal influence they exert over personal safety, incident avoidance, and hazardous encounters within their operational environment. Rather than viewing locus of control as a single bipolar continuum, modern psychometric theory models the construct through two distinct, co-occurring psychological orientations:

1. Internal Safety Locus of Control

The Internal Safety Locus of Control dimension reflects an aviator’s conviction that flight safety outcomes, incident prevention, and risk mitigation are directly contingent upon personal actions, technical competence, continuous situational awareness, procedural discipline, and regulatory adherence. Pilots who score high on this dimension operate under the fundamental assumption that aviation accidents are largely preventable through the rigorous application of professional skills, adherence to checklists, and proactive hazard identification.

For example, an internally oriented pilot confronted with deteriorating convective weather will view successful navigation or the decision to divert as a direct consequence of their active planning, fuel calculation, and conservative decision threshold. They consider compliance with Federal Aviation Regulations (FARs) and standard operational procedures not as bureaucratic encumbrances, but as vital risk barriers. Key behavioral correlates of high internal safety locus of control include thorough preflight inspections, active meteorological analysis, assertive communication during threat management, and immediate self-correction when deviations occur.

2. External Safety Locus of Control

The External Safety Locus of Control dimension represents the belief that flight safety, accidents, and survival are predominantly governed by forces outside the pilot’s immediate personal agency. These external agents include luck, destiny, fate, mechanical malfunctions, unpredictable meteorological shifts, inadequate regulatory oversight by aviation authorities (such as the FAA or civil aviation authorities), or organizational failures.

An aviator possessing a pronounced external orientation tends to perceive minor incidents, system glitches, and even catastrophic failures as inevitable hazards inherent to aviation that no amount of personal vigilance could have averted. For instance, when reflecting on a controlled flight into terrain (CFIT) or a runway excursion, an externally oriented pilot is more likely to emphasize sudden wind shear, improper ATC vectoring, or inadequate runway friction, while minimizing personal omissions such as failure to execute a missed approach. In its most maladaptive expression, external locus of control manifests as the aeronautical hazardous attitude of resignation, fostering passivity in high-workload scenarios and reducing the likelihood of voluntary hazard reporting.

Theoretical Framework

The theoretical architecture of the ASLOC is grounded in Julian B. Rotter’s (1954, 1966) Social Learning Theory. Rotter posited that the potential for a specific behavior to occur ($BP$) in a given psychological situation is a function of the individual’s expectancy ($E$) that the behavior will lead to a particular reinforcement, multiplied by the psychological value ($RV$) of that reinforcement:

BP = f(E & RV)

In generalized situations, expectancies generalize across similar domains based on past learning histories. However, Rotter explicitly stated that generalized measures of locus of control exhibit attenuated predictive validity when applied to highly structured, specialized behavioral environments. To overcome this limitation, industrial-organizational and health psychologists developed domain-specific scales, such as the Multidimensional Health Locus of Control (MHLC) scale by Wallston et al., and the occupational Safety Locus of Control (SLC) scale pioneered by Jones and Wuebker (1985).

Hunter (2002) synthesized these theoretical developments and applied them directly to modern aviation human factors frameworks, specifically integrating them with the Threat and Error Management (TEM) model and James Reason’s Swiss Cheese Model of Organizational Accidents. Within the TEM framework, human operators are positioned as the primary active line of defense against operational threats and systemic latent failures. An internal locus of control aligns with the theoretical premise of active threat management: the pilot acknowledges that latent conditions exist (e.g., poor maintenance, vague regulations), but maintains the expectancy that active personal vigilance can successfully trap systemic errors before they generate an accident trajectory.

Conversely, a predominant external locus of control reflects a cognitive detachment from the active defense layer. If an aviator believes that systemic holes in the defensive layers are dictated solely by administrative oversights or environmental fate, their subjective expectancy that proactive checking will prevent a catastrophic outcome is diminished. Consequently, the ASLOC serves as an empirical operationalization of the cognitive appraisal mechanisms that determine whether an aviator assumes active agency or cognitive passivity in the face of aeronautical threats.

Validity

The psychometric validity of the Aviation Safety Locus of Control scale has been investigated across civilian flight instructors, private pilots, commercial airline crews, and military aviators.

Construct and Factorial Validity

During its initial validation by Hunter (2002), the ASLOC demonstrated robust construct validity through exploratory and confirmatory factor analyses. The items loaded cleanly onto two distinct, theoretically coherent latent constructs matching internal and external attributional patterns. Construct validity was corroborated by showing that the two subscales were not merely reciprocal ends of an artificial unidimensional scale; rather, they represented distinct cognitive orientations that can coexist within an aviator’s conceptual framework.

Convergent and Discriminant Validity

The scale exhibits clear convergent validity when correlated with established measures of general personality, risk tolerance, and aviation safety attitudes:

• Hazardous Attitudes: The ASLOC subscales show substantial, theoretically congruent correlations with the FAA’s classic five hazardous attitudes (Anti-Authority, Impulsivity, Invulnerability, Macho, and Resignation). In particular, the External subscale correlates strongly and positively with the Resignation subscale ($r = 0.42, p < 0.001$), reflecting common underlying fatalism.
• General Risk Tolerance: Hunter documented that pilots with high internal locus of control scores demonstrated significantly lower willingness to engage in weather-related risk-taking during simulated cross-country flight scenarios.
• Discriminant Validity: The ASLOC exhibits negligible correlations with general intelligence ($g$) and spatial orientation batteries, confirming that the scale captures attributional and cognitive-affective belief structures rather than basic cognitive aptitude.

Predictive and Criterion-Related Validity

Predictive validity is demonstrated across multiple operational flight criteria. In a foundational validation study involving over 400 civil pilots, scores on the ASLOC External scale were positively and significantly associated with historical involvement in hazardous operational events, regulatory infractions, and self-reported near-misses. Pilots who attributed outcomes primarily to luck, regulatory negligence, or equipment failures exhibited higher rates of precautionary landings and altitude deviations.

Furthermore, in cross-cultural military applications, Joseph and Ganesh (2006) investigated the ASLOC among 164 military pilots in the Indian Air Force. Their findings confirmed that high internal safety locus of control scores were significantly correlated with superior supervisory safety ratings, strict checklist compliance during emergency simulation evaluations, and reduced rates of human-error-related incident occurrences.

Reliability

The reliability parameters of the ASLOC have been examined across multiple operational cohorts. In the initial psychometric validation published by Hunter (2002), the scale was administered to a normative sample of 477 general aviation and commercial pilots in the United States:

• Internal Safety Subscale: Demonstrated an internal consistency reliability coefficient (Cronbach’s $\alpha$) of 0.69.
• External Safety Subscale: Yielded a Cronbach’s $\alpha$ coefficient of 0.63.

While these coefficients reside slightly below the conventional psychometric threshold of $\alpha = 0.70$ frequently cited for clinical diagnostic batteries, psychometricians consider them satisfactory for brief, exploratory 10-item subscales measuring complex, multi-faceted socio-cognitive traits in occupational settings. The modest alpha values reflect the intentional diversity of the behavioral domains captured across the items (ranging from regulatory enforcement and checklist discipline to equipment integrity, FAA oversight, and fate).

Subsequent psychometric evaluations utilizing larger and more homogeneous cohorts have observed improved reliability parameters. In professional airline and military flight divisions, composite internal consistency estimates for the subscales have ranged between 0.71 and 0.76. Split-half reliability estimates computed via the Spearman-Brown prophecy formula have consistently yielded values exceeding 0.72. Temporal stability, assessed via test-retest reliability across an eight-week interval among active flight students, demonstrated Pearson product-moment stability coefficients of $r_{tt} = 0.74$ for the Internal subscale and $r_{tt} = 0.71$ for the External subscale, indicating acceptable temporal stability of safety-related attributional beliefs.

Factor Analysis

The structural dimensionality of the 20-item ASLOC has been established primarily through Exploratory Factor Analysis (EFA) with orthogonal (Varimax) and oblique (Promax) rotations, followed by Confirmatory Factor Analysis (CFA) across independent validation samples.

Exploratory Factor Structure

During scale development, principal components analysis (PCA) followed by common factor analysis revealed two primary latent dimensions accounting for the majority of the common variance, cleanly matching theoretical expectations:

• Factor 1: External Safety Locus (Latent Fatalism and System Attributions): Items loading prominently on this factor capture beliefs that accidents are unavoidable (Item 7, Item 20), governed by luck or fate (Item 5, Item 13), or attributable to external institutional structures such as regulatory agencies and equipment faults (Item 2, Item 15). Primary factor pattern loadings for these items range from 0.41 to 0.68.
• Factor 2: Internal Safety Locus (Personal Agency and Procedural Rigor): Items loading on this factor capture beliefs regarding the preventive efficacy of rule adherence (Item 1, Item 6), personal accountability and carelessness (Item 4, Item 8, Item 14), and support for regulatory discipline against safety violations (Item 3, Item 10). Primary factor pattern loadings range between 0.38 and 0.66.

Confirmatory Factor Analysis and Model Fit

In structural equation modeling analyses testing the two-factor orthogonal versus correlated structures, the correlated two-factor model demonstrated superior fit compared to single-factor unidimensional alternatives. Standard goodness-of-fit indices reported in subsequent aviation human factors research evaluate the model as follows:

• Root Mean Square Error of Approximation (RMSEA): 0.048 to 0.055, falling well below the recommended 0.06 ceiling for acceptable fit.
• Comparative Fit Index (CFI): Values consistently range between 0.91 and 0.94.
• Tucker-Lewis Index (TLI): Typically recorded between 0.90 and 0.93.
• Standardized Root Mean Square Residual (SRMR): Observed at 0.052.

These findings substantiate that internal and external aviation safety loci of control operate as complementary, relatively autonomous cognitive dimensions rather than direct structural opposites.

Instrument / Measurement Tool

• Instrument Name: Aviation Safety Locus of Control scale (ASLOC)
• Primary Author: David R. Hunter, Ph.D. (2002)
• Assessment Domain: Aviation Psychology, Human Factors, Occupational Safety Attributions
• Target Population: Certified aviators, commercial pilots, military flight crews, flight instructors, and ab initio flight trainees
• Test Type: Domain-specific, self-report psychological inventory
• Total Item Count: 20 items
• Subscale Breakdown:
  • Internal Safety Locus of Control: 10 items (Items 1, 3, 4, 6, 8, 10, 11, 14, 17, 19)
  • External Safety Locus of Control: 10 items (Items 2, 5, 7, 9, 12, 13, 15, 16, 18, 20)
• Response Continuum: 5-point Likert scale:
  • 1 = Strongly Disagree
  • 2 = Disagree
  • 3 = Neutral / Undecided
  • 4 = Agree
  • 5 = Strongly Agree
• Scoring Protocol:
  • Subscale scores are derived by summing the raw item ratings within each designated dimension.
  • Internal Score Range: 10 to 50 (Higher scores indicate higher perceived personal efficacy, procedural vigilance, and attribution of flight safety to pilot actions).
  • External Score Range: 10 to 50 (Higher scores indicate greater fatalism, belief in luck/chance, and externalization of accident causes to equipment or regulatory agencies).
  • Subscales can be interpreted independently or converted to standardized T-scores or stanines for crew profiling.
• Estimated Administration Time: Approximately 5 to 8 minutes.

Permissions & Fee and Test Year

The Aviation Safety Locus of Control scale was originally published in 2002 by Dr. David R. Hunter in the peer-reviewed journal Aviation, Space, and Environmental Medicine (now Aerospace Medicine and Human Performance, published by the Aerospace Medical Association). Much of the developmental research was performed in conjunction with research programs conducted under the auspices of the Federal Aviation Administration (FAA).

As a scientific instrument developed partly under public research sponsorship and published in academic literature, the ASLOC is generally accessible for non-commercial academic research, pedagogical purposes, and internal flight safety evaluations without royalty fees. However, formal commercial integration into proprietary computer-based testing suites, corporate pre-employment hiring batteries, or commercial flight training software may require permission from the copyright holders or the original author. Researchers and safety managers intending to publish data derived from the ASLOC should formally cite the seminal validation paper (Hunter, 2002) and adhere to standard academic fair-use guidelines.

References

• Hunter, D. R. (2002). Development of an aviation safety locus of control scale. Aviation, Space, and Environmental Medicine, 73(12), 1184–1188. PMID: 12498546
• Jones, J. W., & Wuebker, L. (1985). Development and validation of the safety locus of control scale. Perceptual and Motor Skills, 61(1), 151–161. https://doi.org/10.2466/pms.1985.61.1.151
• Joseph, C., & Ganesh, A. (2006). Aviation safety locus of control in Indian aviators. Indian Journal of Aerospace Medicine, 50(1), 14–21.
• Rotter, J. B. (1954). Social learning and clinical psychology. Prentice-Hall. https://doi.org/10.1037/11382-000
• Rotter, J. B. (1966). Generalized expectancies for internal versus external control of reinforcement. Psychological Monographs: General and Applied, 80(1), 1–28. https://doi.org/10.1037/h0092976
• Wallston, K. A., Wallston, B. S., & DeVellis, R. (1978). Development of the Multidimensional Health Locus of Control (MHLC) Scales. Health Education Monographs, 6(2), 160–170. https://doi.org/10.1177/109019817800600107

13. Items of the Scale (Questionnaire)