1. Human factors Forensic investigation
Erin morrissey 4/18/2016

2. Human error and commercial aviation accidents: An analysis using the human factors analysis and classification system
SHAPPELL, S., DETWILER, C., HOLCOMB, K., HACKWORTH, C., BOQUET A., & WIEGMANN, D. A.

3. HFACS Organizational Influences Unsafe Supervision
Climate
Process
Resource Management
Unsafe Supervision
Inadequate
Violations
Preconditions for Unsafe Acts
Environmental
Personnell
Unsafe Acts
Errors

4. Purpose of study
to extend our previous HFACS analyses beyond military and GA to include commercial aviation
to combine the power of a theoretically derived human error framework with traditional situational and demographic variables from the commercial aviation database, such as visual conditions, injury severity, and regional differences
to examine any relationships over an extended period of time (i.e., 13 years).

5. Method 13 years of data as recorded by
National Transportation Safety Board (NTSB)
National Aviation Safety Data Analysis Center (NASDAC)
Included air carrier operations (FAR Part 121) & commuter/on-demand operations (FAR Part 135)
6 pilots, 1,000 min flight hours, 16 hrs. instruction on HFACS
SMEs in HF w/ aviation psych background
Pilots - % 85 agreement
Pilots/HF SMEs - < %5 disagreement

8. Commuter/on-demand operations : environmental factors
Instrument meteorological conditions (IMC)
Visual meteorological conditions (VMC)
Clear = VMC + daylight
Impoverished = IMC + twilight or night

12. results No regional differences (Alaska vs. lower 48)
Flight into IMC under visual flight rules were 5Xs more likely to be attributed to accidents in visually impoverished conditions.
Fatal & non-fatal accidents:
Skill-based errors
Decision errors
Violations*
Perceptual errors
*Violations 3Xs as likely to be associated with fatal accidents.

13. discussion Are violations a form of decision error?
Violations= willful disregard of rules driven by hazardous attitudes
Decision errors= lack of knowledge
Novice pilots -> plan continuation errors
Experienced pilots -> social pressure, overconfidence
Framing a rerouting decision: Loss or gain?

14. Application of a human error framework to conduct train accident/incident investigations
Reinach, S., & Viale, A.

15. Purpose To modify the HFACS to other domains
Retrospective and prospective data collection/analysis (Janus)
Provides consistency to investigation
Ensures thoroughness
Counteracts heuristics & biases
Enables comparison of contributing factors across industries.

16. Remote control locomotive
In an effort to reduce operating costs and increase safety, RCL operation have been implemented in railroad switching yards.
Teams work in pairs

17. Method
FRA reportable accidents & incidents from all 7 U.S. & Canadian Class I freight railroads.
Accidents = collisions and derailment > $6700 damages
Incidents = employee injuries requiring more than basic first aid
May – Oct, 2004
6 accidents/incidents investigated further using the HFACS-RR framework

18. HFACS-RR framework Outside factors* Organizational factors
Economic/Political/Social/Legal Environment
Organizational factors
Organizational climate; Resource mgmt.; processes
Supervisory factors
Inadequate supervision; Supervisory contraventions
Preconditions for operator acts
Environmental; Personnel factors; Condition of operators
Operator acts
Errors; Contraventions

19. In 6 months… 29 collisions 25 derailments 13 employee injuries
----Select
46 contributing factors
36 probable contributing factors

24. Discussion
Operating remotely eliminates visual, aural, and kinesthetic feedback to operator reducing SA
Staffing & Training demands increase as experienced employees retire while rail volume increases
Importance of identifying latent conditions