Applied Human Factors in Aviation Maintenance

Manoj S. Patankar, James C. Taylor

• Publisher: Routledge
• Year: 2017
• Print ISBN: 9780754619406
• eBook ISBN: 9781351957670
• Topic: Tecnología e ingeniería
• Subtopic: Ingeniería industrial

Considering the global awareness of human performance issues affecting maintenance personnel, there is enough evidence in the US ASRS reports to establish that systemic problems such as impractical maintenance procedures, inadequate training, and the safety versus profit challenge continue to contribute toward latent failures. Manoj S. Patankar and James C. Taylor strongly believe in incorporating the human factors principles in aviation maintenance. In this, their second of two volumes, they place particular emphasis on applying human factors principles in a book intended to serve as a practical guide, as well as an academic text. Features include: - A real 'how to' approach that serves as a companion to the previous volume: 'Risk Management and Error Reduction in Aviation Maintenance'. - Self-reports of maintenance errors used throughout to illustrate the systemic susceptibility for errors as well as to discuss corresponding solutions. - Two tools - a pre-task scorecard and a post-task scorecard - introduced as means to measure individual as well as organizational safety performance. - Interpersonal trust and professionalism explored in detail. - Ethical and procedural issues associated with collection and analysis of both qualitative as well as quantitative safety data discussed. The intended readership includes aviation maintenance personnel, e.g. FAA-type aircraft mechanics, CAA-type aircraft maintenance engineers, maintenance managers, regulators, and aviation students.

Chapter 1
Implementing Human Factors in Maintenance: Individual, Organizational and Collegiate Perspectives

Instructional Objectives

Upon completing this chapter, you should be able to accomplish the following:

1. Describe how mechanics were able to apply their human factors training to change their individual behavior.
2. Discuss specific ways to implement human factors principles at the individual level.
3. Describe how certain organizations were able to garner support to implement and sustain human factors/safety initiatives.
4. Explain how human factors training could be incorporated in a collegiate aviation maintenance curriculum.
5. Discuss the factors that contribute toward the success of human factors programs.
6. Discuss the factors that contribute toward the failure of human factors programs.
7. Discuss the influence of regulatory initiatives such as JAR 66, and 145, as well as FAA's AC 120-16D and 120-79 on application of human factors principles in aviation maintenance.

Introduction

In this chapter, we will review some of the topics typically covered in most awareness-level courses and focus on the implementation of those topics, from a behavioral perspective, at three levels: individual, organizational, and collegiate. We will use specific examples from NASA's Aviation Safety Reporting System (ASRS) reports as well as the Joint Aviation Authorities' JAR 66 and 145 requirements to illustrate our recommendations. Additionally, we will discuss the implications of the Federal Aviation Administration's Advisory Circulars 120-16D Air Carrier Maintenance Programs and 120-79 Developing and Implementing a Continuing Analysis and Surveillance System from the perspectives of organizational change and commitment.

A Review of Human Factors Awareness Topics

Typical human factors training programs in the aviation maintenance industry have been dominated by awareness-level training, also called 'third generation MRM programs' (Patankar & Taylor, 2004, pp. 66-77). The curriculum for such a training program typically included the following components:

1. Dirty Dozen elements: Lack of communication, complacency, lack of knowledge, distraction, lack of teamwork, fatigue, lack of resources, pressure, lack of assertiveness, stress, lack of awareness, and norms. Safety nets associated with each of these elements are also discussed.
2. Accident case analysis·. One or more exercises designed to illustrate how a chain of events (at times each event is a minor deviance) can lead to disastrous consequences.
3. Organization-specific problem: Focus on a particular problem that the organization wants to rectify immediately. Examples of such problems include shift turnovers, logbook errors, ground damage, or lost-time injuries.
4. Interactive exercises: Typically, the training also included at least one interactive exercise to illustrate concepts such as the value of teamwork or hazards of verbal turnovers.

In general, we have observed that such training programs have been very effective in raising the awareness of individuals—their enthusiasm about the training was elevated soon after the training and they expected that such training would improve safety. As time progressed, the participants' enthusiasm declined, and in some cases it even reversed to strong negative feelings, due to 'lack of management follow-up' (Taylor & Robertson, 1995; Taylor, 1998; Taylor, 2000). As we continue to contemplate the meaning of 'lack of management follow-up', we are realizing that perhaps it means different things to different people, and also, at different times. For example, in some cases it might mean that the workforce simply expected a follow-up or a recurrent training program; in other cases, it might mean that the workforce expected the management to solve all the problems identified by the workforce as a result of their new-found knowledge about maintenance human factors; and in some other cases, it might mean that the workers are ready to make changes in their individual work habits, but they also need to see that the management is willing to support organizational changes (examples include scheduled shift overlap to allow for better turnovers, streamlined document change process to allow for easy revisions to maintenance procedures, provision of proper tools to minimize the use of inappropriate tools, etc.). Therefore, two things are clear: first, management support is paramount, and second, that support is different for different people/organizations and at different times.

Assuming that you have been through an awareness-level course in maintenance human factors, we will now focus on specific implementation issues at individual, organizational, and collegiate levels.

Incidentally, if you have not taken a basic Human Factors in Maintenance course, please visit the following websites for a primer:

1. http://hfskyway.faa.gov
2. http://www.iata.org/ps/training/courses/taltl0_04.htm
3. http://www.caa.co.uk/docs/33/CAP716.pdf

Individual Perspectives

As a result of awareness-level training programs, we discovered that the majority of the trainees were able to make some passive, individual changes. For example, they said that they were more aware of safety issues, they tried to listen to turnovers more carefully, they double-checked their work, or they understood how stress, fatigue, and distraction could affect the quality of their work. Overall, most people admitted to making some changes that were within their personal span of control.

In order to convert the above passive changes into active changes, we offer guidance in the following skills:

1. Communication: Practice closed-loop communication—try to provide feedback to others that you understood their message.
2. Assertiveness: Assertiveness includes speech as well as actions. Speak-up to identify discrepancies, but also act to follow through on your responsibilities
3. Preparation: Be prepared, physically, intellectually, and emotionally, to handle the job at hand. If not, alert your colleagues of your weaknesses.
4. Work Management. Understand your strengths and weaknesses prior to embarking on the job so that you are able to better manage the tasks at hand: organize, prioritize, and maintain situational awareness. Above all, shield against distractions.
5. Integrity·. Learn to stand-up to your convictions. Safety is your fundamental responsibility. Do not sign-off all items in one sitting, do not assume anything, and do not forget to document all your actions.
6. Teamwork: Teamwork is difficult to practice in the maintenance environment because the reward and penalty structure is based on individual-level certification authority. However, good teamwork can improve safety and job satisfaction for all. Look for opportunities to share your abilities and skills with others on your crew.

Now, let us discuss each of the above areas in more detail using specific examples from the NASA Aviation Safety Reporting System (ASRS) maintenance dataset—a set of de-identified error reports voluntarily submitted by mechanics in the United States.

Communication

Communication involves a transmitter (the one sending the message), a medium (such as technical/legal document or a shift turnover/handover), and a receiver (the one receiving the message). Typically, the transmitter simply sends the message without confirming that the message has been received and understood by the receiver. Since humans are not perfect, sometimes we simply think that we have sent the message! Therefore, to close the loop, & feedback system needs to be implemented. This feedback system should not only confirm that the message has been received, but also confirm that it has been interpreted in the intended sense. Sometimes, the medium used to convey the message tends to impede clear interpretation. Consider Example 1.1. It illustrates how the incomplete and confusing maintenance instructions, impractical tools/equipment, and conflicting organizational policies could setup one mechanic into committing errors. A closed-loop communication process could be used to seek clarification regarding maintenance instructions or to change them so that they can be accomplished as published.

Example 1.1: A case of incomplete and confusing instructions

ASRS Report Number 459526

(Public document, edited for clarity)

Aircraft xyz returned to zzz with smoke in cabin. Secured leaking APU and performed the required operation xwx. This operation is new at air carrier as of dec/xa/99. The job card refers to maintenance manual 21-20-02-2 for a duct burnout. Found maintenance manual to be very hard to follow as to which sense lines must be capped because instructions do not match illustrations. The instructions call for 2 lines to be capped, but illustrations show 3 lines to be capped. Zzz does not allow for the APU compartment to be pressure washed on the ramp, so compartment was wiped with solvent and rags. This is allowed per job card, but all the oil cannot be removed from acoustic liner of APU inlet. In hindsight, APU should have been placed on maintenance callout. Job card signoff card should have separate signoff for each job function, but several functions are included under 'perform duct burnout'. The job card instructions (step 4) say to do duct burnout per maintenance manual 21-20-02-2. The maintenance manual 21-20-02-2, item 7-c does not tell you to replace the coalescer bags. But if you read job card step 4 instructions, replacing coalescer bags and cleaning the water separators is included under 'perform duct burnout'. The job cards should have a separate signoff for coalescer bag replacement. The tooling provided by air carrier will not allow the burnout procedure to be performed as per maintenance manual. The leads and hoses for test equipment will not reach the cabin as required. Air carrier provided the kit, but did not provide any training on its use or on how to perform the test. Due to the discrepancies in the job card and maintenance manual, as well as the incomplete and vague instructions, I am not completely sure that I performed this operation properly.

Another problem with the most technical publications used to communicate maintenance instructions is that there is no clear way to determine whether the specific instructions that are used by the mechanics are in fact the most current; this is especially true for older aircraft and in remote maintenance facilities.

Interpersonal communication is absolutely critical among aircraft maintenance personnel for the following reasons: (a) it minimizes the probability of injuring oneself or others working on the aircraft, (b) it keeps all mechanics fully informed about the several maintenance actions that tend to be carried out simultaneously and have a tendency of having interconnected consequences, and (c) it minimizes complacency among people who have worked together for long periods of time. While working in shifts, it is imperative that mechanics from two linked shifts have a face-toface conversation about the job in progress. In the United States, the typical organizational structure in most airline maintenance organizations is as follows: three-to-five mechanics holding an FAA Aircraft Mechanic Certificate are supervised by a lead mechanic and several leads are supervised by either a foreman or a team leader. Typically, mechanics provide status reports to their leads and the leads provide status reports to the foremen. The outgoing foremen may talk with the incoming foremen, and the outgoing leads may talk with the incoming leads, but the outgoing mechanics rarely talk with the incoming mechanics. Therefore, the actual mechanics taking over the job in progress may have very limited, and sometimes incorrect, information about the job. In the case described in Example 1.2, it is clear that the mechanics were using a 'generic' maintenance manual. Both shifts were aware that the manual was generic. Therefore, the shift that removed the engine and the propeller should have noted any inconsistencies between the pre-existing assembly and the diagram provided in the manual. At least, since most of the people at that maintenance facility worked on 100-series aircraft, they should have noted that the engine control cables were installed on the opposite side on the 200-series aircraft. If they had observed this difference, it would have been prudent to provide a detailed turnover/handover to the incoming shift. It is also interesting to note that the post-rigging inspection was carried out 'in accordance with the maintenance manual'. So, if the maintenance manual was vague or incorrect, the inspection is not likely to be effective in detecting errors.

Example 1.2: A case of an incomplete communication

ASRS Report Number 365609

(Public document, edited for clarity)

On the weekend of April/xx/97, one of our 200 series Dash 8s ferried to our base for an engine change, propeller change, and sheet metal repairs. Our base here in zzz normally only works on 100 series Dash 8s. On Saturday, a crew removed and replaced the P&W 123 engine but did not install the propeller nor did they rig the engine controls. On Sunday another mechanic and I were told by our supervisor to install the propeller and to get the aircraft ready for an xx00 departure. The propeller installation and engine rigging was complied with and inspected in accordance with the maintenance manuals.

The event was caused by the nacelle mounted control rods being installed on the wrong side of the levers at the engine's fuel control. The correct side was opposite of what was in the manual.

The main contributing factors were that the manuals were incorrect and not specific [to the model being serviced], lack of training, and a poor turnover from the crew that removed and replaced the engine. The situation was discovered during a revenue flight on the next day when the crew reported that the power and condition levers for that engine bound up. The crew was able to free the levers and continued and completed their flight.

Ideally, shift turnovers should include a written narrative, a verbal explanation, and a face-to-face show-and-tell session—mechanics to mechanics, leads to leads, and foremen to foremen. In case face-to-face meetings between mechanics are not practical, the written turnovers/handovers serve as descriptive documentation between the direct parties involved in the performance of the maintenance actions. In one company, we have noticed foremen using turnover logs to communicate with each other, but sometimes, they do not walk over to the aircraft and review the physical status of the job. At least the written logs serve as reminders, and because they are not required by the Federal Aviation Regulations, there is little reason to expect such turnovers other than as a 'best practice' at this particular company.

The U.K. CAA's CAP 716 (CAA, 2003) presents detailed guidance on shift-turnovers/handovers. We certainly support all those recommendations. To provide further guidance in improving shift-turnovers, we recommend that a 3-copy maintenance log form be used: one copy would stay with the mechanic who gave the turnover; one copy would be given to the mechanic who accepted the turnover; and one copy would be given to the supervisor—via the lead mechanic—to be filed with aircraft records that are to be maintained with the aircraft. The mechanics should retain their copies for future reference. Such a maintenance log ...

Table of contents

• Cover
• Half Title
• Dedication
• Title
• Copyright
• Contents
• List of Examples
• List of Figures
• List of Tables
• Preface
• Acknowledgments
• 1. Implementing Human Factors in Maintenance: Individual, Organizational and Collegiate Perspectives
• 2. Moving from Awareness to Implementation
• 3. Pre-Task Analysis
• 4. Post-Task Analysis
• 5. Professionalism and Trust: The Dual Mandate for Improvements in Safety
• 6. Safety Data Collection and Analysis
• References
• Index