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Statistics, showing that procedural deviation is the highest-ranking category in crew- or operator-caused accidents. This is also true in the nuclear industry, and in the maritime industry. However, the aviation industry is moving toward an environment in which airline standard operating procedures are so rigidly enforced that line pilots rarely stray outside their constraints. These pilots are intimidated or bullied by trainers, check pilots for even thinking about deviating. Unfortunately that condition is what they get comfortable with and it’s how they eventually learned to use automation systems. Standard Operating Procedures (SOPs) were originally intended to be guidelines. The result is a very standard use of flight deck and ground automation within the confines of those strict SOPs. The assumption of the adequacy of SOPs in all situations leads to the limiting of not only the understanding of the automation but the degree to which it’s use is managed and/or employed in the right situations. The zealous enforcement of SOPs is seen as a barrier to weakened flying skills, the lack of pilot aviation knowledge, a decreasing level of pilot experience throughout the industry, and the rapidly rising level of automation sophistication and dependence on it.

Management must recognize the danger of over-procedurization, which fails to exploit one of the most valuable assets in the system, the intelligent operator who is “on the scene.” The alert system designer and operations manager recognize that there cannot be a procedure for everything, and the time will come in which the operators of a complex system will face a situation for which there is no written procedure. Procedures, whether executed by humans or machines, have their place, but so does human cognition.

Proceduralization is linked to the general push toward bureaucratization of an ever-growing number of aviation activities.  Certification and flight-standards regulatory agencies progressively extend their fields of intervention along procedural lines, but oftentimes lack the operational knowledge, experience, manpower, and an in-depth understanding of the conditions under which aviation safety has been concretely achieved and socially produced.  Reinforcing proceduralization remains a widely accepted, pro-forma response when safety barriers are perceived to be insufficient.  It is easier to audit and assess deviations from procedures or processes than to understand and assess the social construction of safety on a case-by-operational-case.  Reports and analyses all point toward complex organizational adjustments and unbearable constraints that little by little, push pilots, air traffic controllers, mechanics and other players into uncharted territories for which no standardized procedures are adequate.  A deep understanding of the conditions under which people operate daily (including reporting on their assumptions, beliefs, difficulties, instinctive responses, expertise, successes, and so on) is required that doesn’t depend on paperwork audits.  One of the most recent (and paradoxical) targets of proceduralization is the safety culture itself.*

Potential hazard

  1. Lack of recognition of the appropriate use of automation systems in the proper contexts
  2. Confused, lack of certainty or simply lack of confidence in when to employ procedures and automation which often leads to its inappropriate or ineffective use
  3. Failure of regulated training syllabi to communicate under what circumstances and how automation is to be used.
  4. Weakened pilot skills
  5. Lack of pilot aviation knowledge
  6. Decreasing pilot experience
  7. Little experience among the population of freshly minted MPLs and low time F/O’s who really know their SOPs
  8. Strictly adhere to SOPs at the expense of the aviate, navigate, communicate when presented with a non-standard in-flight situation
  9. In those cases where some function of the automation provides a potential hazard, a manual alternative must be provided
  10. Inability to find written procedures for key safety situations in neither: (1) the Flight Operational Manual, (2) the Supplemental section in the flight manual, (3) Operations Bulletin, (4) the aircraft newsletter, and (5) nor on dispatch paperwork


  1. The necessity of zealous enforcement of SOPs on weakened flying skills, coupled to
  2. Lack of pilot aviation knowledge,
  3. Decreasing level of pilot experience throughout the industry and the
  4. Rapidly rising level of automation sophistication and dependence on it.
  5. How do we address this in training? Simple.
  6. Recognize what the student needs when he/she needs it.
  7. Get off the regulated training syllabus and address the issue right then and there.
  8. Teach them why and how SOP deviation might be the more effective solution and
  9. What an appropriate level of automation looks like in that situation.
  10. It could give some weaker pilots increased ability while elevating their confidence.
  11. Knowledge is power (lack of knowledge gives self confidence).

Corroborating sources and comments

Added March 2014

– Adapted from personal communications from Allan Dunville, Training Captain with Bombardier Aircraft and Trapping Safety Into Rules: How Desirable or Avoidable is Proceduralization?, Bieder, Corrine, & Bourrier, Mathilde, 2013, Ashgate Publishing Limited, Surrey, England

Degani, Asaf & Wiener, Earl L., Procedures in Complex Systems: The Airline Cockpit, IEEE Transactions on Systems, Man & Cybernetics, SMC-27(3), pp. 302-312

Trager, E. A. (1988). Special study report: Significant events involving procedures

(Office for Analysis and Evaluation of Operational Data AOED/S801). Washington DC: Nuclear Regulatory Commission

Perrow, C. (1984). Normal accidents. New York: Basic Books

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