Dirty Dozen

Gordon Dupont, formerly of Transport Canada, is one such consultant whose excellent “Dirty Dozen” classification of HF root causes has been widely adopted by several aviation organizations. These are encapsulated in a set of 12 posters, Figure 2.17 depicting cartoon scenarios showing what and how we should avoid it.

1- Lack of communication 2- Complacency

3- Lack of knowledge 4- Distraction

5- Lack of Team Work 6- Fatigue

7- Lack of resources 8- Pressure

9- Lack of assertiveness 10- Stress

11- Lack of awareness 12- Norms

Figure 2.17 : “The Dirty Dozen.” From Gordon Dupont, System Safety Services

2.10.2 MEDA [20]

Other organizations like Boeing have developed their own in-house Maintenance Error and Decision Analysis (MEDA) programs with more in depth analysis including the background of personnel that commit these HF errors to better understand the extent of solutions necessary. Most of these programs are designed to identify the HF errors, educate the personnel on their causal potential, suggest ways to contain and correct the problem and create a HF error-free environment. While many of these programs have truly made the aviation work environment safer, many of them still look at HF from a people’ perspective rather than “an organization” develop programs that improve the performance of which will provide long term solutions to HFIM.

The MEDA Philosophy

Traditional efforts to investigate errors are often aimed at identifying the employee who made the error. The usual result is that the employee is defensive and is subjected to a combination of disciplinary action and recurrent training (which is actually retraining). Because retraining often adds little or no value to what the employee already knows, it may be ineffective in preventing future errors. In addition, by the time the employee is identified, information about the factors that contributed to the error has been lost. Because the factors that contributed to the error remain unchanged, the error is likely to recur, setting what is called the "blame and train" cycle in motion again.

To break this cycle, MEDA was developed in order to assist investigators to look for the factors that contributed to the error, rather than concentrate upon the employee who made the error. The MEDA philosophy is based on these principles:

- Positive employee intent (maintenance technicians want to do the best job possible and do not make errors intentionally).

- Contribution of multiple factors (a series of factors contributes to an error).

- Manageability of errors (most of the factors that contribute to an error can be managed).

Positive Employee Intent

This principle is key to a successful investigation. Traditional "blame and train"

investigations assume that errors result from individual carelessness or incompetence. Starting instead from the assumption that even careful employees can make errors, MEDA interviewers can gain the active participation of the technicians closest to the error. When technicians feel that their competence is not in question and that their contributions will not be used in disciplinary actions against them or their fellow employees, they willingly team with investigators to identify the factors that contribute to error and suggest solutions. By following this principle, operators can replace a negative "blame and train" pattern with a positive "blame the process, not the person" practice.

Contribution of Multiple Factors

Technicians who perform maintenance tasks on a daily basis are often aware of factors that can contribute to error. These include information that is difficult to understand, such as work cards or maintenance manuals; inadequate lighting; poor communication between work shifts; and aircraft design. Technicians may even have their own strategies for addressing these factors. One of the objectives of a MEDA investigation is to discover these successful strategies and share them with the entire maintenance operation.

Manageability Of Errors

Active involvement of the technicians closest to the error reflects the MEDA principle that most of the factors that contribute to an error can be managed. Processes can be changed, procedures improved or corrected, facilities enhanced, and best practices shared. Because error most often results from a series of contributing factors, correcting or removing just one or two of these factors can prevent the error from recurring.

The MEDA Process

To help maintenance organizations achieve the dual goals of identifying factors that contribute to existing errors and avoiding future errors, Boeing initially worked with British Airways, Continental Airlines, United Airlines, a maintenance workers' labour union, and the U.S. Federal Aviation Administration. The result was a basic five-step process for operators to follow

• Event.

• Decision.

• Investigation.

• Prevention strategies.

• Feedback.

Event

An event occurs, such as a gate return or air turn back. It is the responsibility of the maintenance organization to select the error-caused events that will be investigated.

Decision

After fixing the problem and returning the airplane to service, the operator makes a decision: Was the event maintenance-related? If yes, the operator performs a MEDA investigation.

Investigation

Using the MEDA results form, the operator carries out an investigation. The trained investigator uses the form to record general information about the airplane, when the maintenance and the event occurred, the event that began the investigation, the error that caused the event, the factors contributing to the error, and a list of possible prevention strategies.

Prevention Strategies

The operator reviews, prioritises, implements, and then tracks prevention strategies (process improvements) in order to avoid or reduce the likelihood of similar errors in the future.

Feedback

The operator provides feedback to the maintenance workforce so technicians know that changes have been made to the maintenance system as a result of the MEDA process. The operator is responsible for affirming the effectiveness of employees'

participation and validating their contribution to the MEDA process by sharing investigation results with them.

Management Resolve

The resolve of management at the maintenance operation is key to successful MEDA implementation. Specifically, after completing a program of MEDA support from Boeing, managers must assume responsibility for the following activities before starting investigations:

a) Appoint a manager in charge of MEDA and assign a focal organization.

b) Decide which events will initiate investigations.

c) Establish a plan for conducting and tracking investigations.

d) Assemble a team to decide which prevention strategies to implement.

e) Inform the maintenance and engineering workforce about MEDA before implementation.

MEDA is a long-term commitment, rather than a quick fix. Operators new to the process are susceptible to "normal workload syndrome". This occurs once the enthusiasm generated by initial training of investigation teams has diminished and the first few investigations have been completed. In addition to the expectation that they will continue to use MEDA, newly trained investigators are expected to maintain their normal responsibilities and workloads. Management at all levels can maintain the ongoing commitment required by providing systematic tracking of MEDA findings and visibility of error and improvement trends.

Summary

The Maintenance Error Decision Aid (MEDA) process offered by Boeing continues to help operators of airplanes identify what causes maintenance errors and how to prevent similar errors in the future. Because MEDA is a tool for investigating the factors that contribute to an error, maintenance organizations can discover exactly what led to an error and remedy those factors. By using MEDA, operators can avoid the rework, lost revenue, and potential safety problems related to events caused by maintenance errors.