Human Factors in Maintenance

Surveys reveal the importance of regulations mandating human factors
programs.

By William B. Johnson, Ph.D., and Carla Hackworth, Ph.D.

Despite the existence of human factors programs in aviation maintenance
since the late 1980s, such programs are not required throughout the
world, and those that do exist are far from standardized. In 2006 and
2007, the U.S. Federal Aviation Administration (FAA) conducted two
large-scale surveys that gave the international maintenance community
and FAA aviation safety inspectors (ASIs) an opportunity to report
progress and identify the human factors issues that need immediate
attention. High response rates and frank answers to the surveys gave a
clear view of the status and showed the direction future work should
take.

During the 1980s, many flight organizations were enhancing safety by
adopting cockpit resource management (CRM) programs. Flight crews were
finding means to ensure and improve safety by focusing on teamwork,
communication and developing operating procedures. The term evolved to
become "crew" resource management and expanded to include a variety of
human factors that affect performance and safety, such as fitness for
duty, fatigue, nutrition and health, safety culture and much more. There
is no question that CRM has improved the safety of flight.

In 1988, the Aloha Boeing 737 fuselage-failure accident was the first of
a number of significant events that focused attention on human factors
in maintenance. That year, the U.S. Congress passed the Aviation Safety
Act which directed the FAA to conduct research on all aspects of human
performance in aviation, including maintenance, launching the
development of FAA's maintenance human factors research programs that
continue today.

Continental Airlines in 1989 became the first to expand CRM and human
factors principles to maintenance and engineering, introducing its Crew
Coordination Concepts program. By the early 1990s, US Airways, with
significant FAA research and development (R and D) participation, began
their Maintenance Resource Management effort. Both programs continued
for years, but without regulatory requirements to continue, they faded
away when lean times arrived for the U.S. carriers.

By the mid-1990s, Transport Canada (TC), the U.K. Civil Aviation
Authority and the FAA started an annual conference titled "Human Factors
in Maintenance and Inspection." That conference provided excellent
information exchange until 2002, when it took a hiatus until 2006.
During that period, both TC and the Joint Aviation Authorities --- now
replaced by the European Aviation Safety Agency (EASA) --- enacted
regulations requiring initial and continuing human factors training for
all maintenance personnel. At the same time, the FAA continued its human
factors R and D, publishing extensive human factors guidance materials
for U.S. domestic and international applications. The FAA also initiated
human factors training for all of their nearly 1,800 ASIs. An expanded
version of that training continues today. Yet, in spite of the extensive
R and D, guidance material and internal employee training, the FAA has
not issued a regulation requiring the industry to provide training for
human factors in maintenance.

**Regulatory Differences**

Meanwhile, TC, EASA, the Civil Aviation Safety Authority of Australia
and other regulatory agencies have adopted regulations for maintenance
human factors programs. That situation prompted the authors to assess
the status of human factors programs in maintenance organizations and
airlines throughout the world. In addition, the FAA wanted to understand
maintenance human factors in the United States as viewed by their ASI
work force.

The international survey was developed in cooperation with the EASA's
European Human Factors Working Group, both surveys were Web-based, and
respondents' answers were anonymous.^1^ The industry questionnaire
contained 78 items; the FAA survey had 45 questions. For the most part
the surveys used five-point rating scales and provided open-ended
opportunities for comments. The surveys discussed here are more fully
described separately.^2,\ 3,\ 4^

The goals of the industry survey were to assess the current status of
human factors programs, including:

-   Training;

-   Fatigue management;

-   Leadership commitment;

-   Error report systems;

-   Use of technical documentation; and,

-   Program cost justification.

And, most importantly, the survey was designed to assess the differences
between mandatory and voluntary programs.

The international industry respondents had a lot to say. The invitation
was sent to over 600 valid e-mail addresses. Responses numbered 414, an
unusually high 66 percent response rate, and included input from
management, quality control, training and labor representatives in 54
countries. The highest percentage of respondents --- 40 percent ---
worked within the United States. Some of the other countries included
Canada, 9 percent; United Kingdom, 7 percent; and Australia, Norway and
Singapore, all 3 percent (Figure 1).

The survey sample spanned the entire aircraft maintenance industry, with
more than one-third from an airline maintenance department, 27 percent
from repair stations, 9 percent in a general aviation/business
operation, and 6 percent at a training facility or maintenance school.
While specific respondent affiliation was secure and anonymous, it is
estimated that approximately 200 organizations responded (Figure 2).

FAA-regulated maintenance operations were the most numerous, followed by
those governed by EASA rules (Table 1).

Regulations that require human factors programs make a difference,
respondents said. To a question regarding the motivation for human
factors programs, the two responses most frequently selected were flight
safety and worker protection, followed by regulatory compliance and cost
control.

While these responses reflect positively on the industry, results from
this question likely were skewed by the high percentage of FAA-regulated
respondents, who are not required to have a program. However, answers to
further questions showed that those who had to comply with regulations
indicated their programs were more robust, provided better training for
instructors and trained higher percentages of staff.

But human factors programs go beyond regulations. The survey inquired
about many aspects of a total human factors program, including topics
such as use of error management systems, fatigue management and
training, cost justification of human factors programs and technical
documentation systems.

Some 55 percent of the respondents reported that error data were stored
in a database, and less than half of all those responding said their
database was reviewed in a proactive manner. In this day of increased
attention to safety management systems (SMS), a data-driven process,
that number is not high enough. The response indicates that there is
plenty of opportunity for improvement and reinforces the idea that the
collection of data, while challenging, is easier than data analysis. The
SMS challenge is to discover what the data are telling us.

Fatigue is a safety issue in maintenance, according to 82 percent of the
respondents. However, only 25 percent had a fatigue management system,
and just 36 percent covered fatigue in the training program. This
discontinuity between recognizing the fatigue threat and establishing
barriers is alarming, and it was repeated in the inspector survey.

Less than 10 percent of respondents reported that an effort had been
made to show a return on investment in human factors programs even
though 51 percent said such information was important. Clearly, the
industry must improve methods to assess the financial return on human
factors programs if such programs are to flourish and expand beyond
minimum regulatory requirements. The lack of justifications helps
explain why the apparently successful voluntary programs from the early
1990s became victims of hard financial times. Those programs "felt"
good, but did not take the time to prove their financial worth.

More than 70 percent of respondents' companies had a formal or informal
policy to apply human factors considerations to the development or
modification of documentation.

Proper use of technical documentation remains a very high priority for
the industry. Failure to follow procedures is the no. 1 cause of most
negative events, and human factors issues are often a root cause of
documentation events. When people do not use documents correctly, event
investigations must drill down to discover the reasons, not just assign
blame. Effective use of error reporting systems is a very good way to
raise human factors-related attention to technical documentation and
procedures.

The industry survey indicates that the following are the best
opportunities for improving how human factors are handled in
maintenance:

-   Use of event reporting data, creation of a fatigue management
    program;

-   Increased use of data to provide cost justification of human factors
    programs; and,

-   Greater attention to the human factors aspects during the
    development and use of technical documentation and procedures.

**Inspectors and Human Factors**

The second survey, completed in 2007, focused on the FAA inspector work
force. The FAA survey had these goals:

-   To gather opinions regarding the perceived level of human factors
    knowledge among the ASI work force;

-   Assess the level of human factors support for ASIs;

-   Obtain an inspector's view of human factors programs in the
    industry; and,

-   Identify workplace challenges both for the aviation maintenance
    industry and for the FAA.

The inspectors capitalized on the opportunity and the survey obtained
provided approximately 180 open-ended comments.

As with the industry survey, there was a high response rate. The
voluntary participation by more than 800 ASIs meant that nearly 45
percent of FAA's inspectors participated.

The inspectors generally were evenly divided between the airlines and
general aviation, with the airline group slightly larger (Table 2). More
than 80 percent of the respondents performed surveillance as part of
their job and had maintenance experience in excess of 20 years. Some 44
percent of the inspectors reported that the companies they oversee
comply with EASA rules with respect to human factors. Thus, the FAA ASIs
are seeing a lot of human factors programs, but not because of FAA
regulations.

A high percentage of FAA inspectors, 64 percent, said the human error
investigations they see in the U.S. industry tend to be informal. In a
separate item, 12 percent of the ASIs said their operator's human
factors practices were implemented extensively. The informality of the
programs may be reasonable because good programs are not necessarily
highly structured. Instead, they should be designed to fit the company
culture and requirements derived from error reporting systems.

The 12 most common causes of human error in maintenance, named the
"Dirty Dozen" by Canadian safety specialist Gordon Dupont, were
presented for inspectors to rank the challenges (see sidebar). The top
three for maintenance were pressure, complacency and the use of norms
--- that is, the use of unwritten practices. The combination of these
top-rated causes of error can contribute to the failure to use technical
documentation, which surprisingly was rated only as the fifth on the
inspectors' rating of challenges despite the fact that documentation
issues are unarguably the leading contributor to maintenance error.

FAA inspectors rated the important attributes/programs for a quality
maintenance organization and overwhelmingly identified a positive safety
culture --- 91 percent --- and an SMS --- 82 percent --- as the most
important (Table 3). FAA management, especially from the Aviation Safety
office (AVS), has been "walking the walk" with respect to safety culture
and SMS, evidenced by the organization's recent ISO9000 certification
and establishment of a new office dedicated to gathering, analyzing and
sharing data.

Fatigue is a concern for the aviation industry.^5^ Nearly 40 percent of
ASIs responded that maintenance employee fatigue is a safety issue for
the operators they oversee. Airline inspectors saw this as a greater
issue --- 43 percent --- than did GA inspectors --- 35 percent. Both
categories of inspectors reported a need for regulations related to
fatigue issues in maintenance, 91 percent for airline ASIs and 75
percent for GA inspectors. The FAA has ongoing research initiatives that
are providing guidance and procedures to address fatigue in the
maintenance workplace. This R and D involves a planned mix of approaches
addressing issues including the science of fatigue and sleep,
applications for nano-technology sensors, real-time human performance
modeling, advanced technology scheduling practices, economics of
maintenance worker compensation practices and accident investigation
analysis related to fatigue.

The FAA's three-day employee course, "Human Factors in Aviation
Maintenance," is now required training; half of all airworthiness ASIs
attended the previous two-day class. Two-thirds of the respondents
indicated that they want biennial recurrent training in human factors;
EASA requires biennial recurrent training for its certificate holders.

During 2006 and 2007, FAA released two operator's manuals for human
factors, one for maintenance that received the FAA Administrator's Plain
Language Award for 2006, and the other a report for airport
operations.^6^ ASIs indicated a limited familiarity with the maintenance
operator's manual, suggesting that the FAA must not only publish
guidance materials but also promote them both internally and externally.

Inspectors used the "Dirty Dozen" to rate their own job challenges,
rating distraction, lack of resources and pressure as their greatest
challenges. There were many comments providing positive suggestions to
improve inspectors working efficiency. Inspectors recognized the
emerging requirement for additional oversight of domestic and
international repair stations and said they knew that inspectors face a
workload that is growing faster than the work force.

Inspectors said that there should be an FAA regulation for human factors
programs, with 80 percent of airline inspectors and 72 percent of GA
inspectors backing the idea. Their positions were reinforced by numerous
comments that generally said that airline maintenance organizations are
driven by regulations and will invest resources to follow the rules.
When there are human factors regulations, there will be compliance by
all. Until then, human factors programs will exist only where there are
EASA certificates and/or enlightened U.S. maintenance organizations.

Combining Survey Data

The high rate of response to both voluntary surveys was evidence of a
high interest in maintenance human factors. Respondents had positive
attitudes and reported what they believed were the best opportunities
for improvement. FAA inspectors were generally positive in their
rankings and candid in their responses about maintenance human factors.
Their comments demonstrated an understanding of the impact of human
factors programs in maintenance organizations. Many of the comments
originated from the ASI's past employment in the airline maintenance
industry.

There was general agreement between the two surveys that the no. 1
challenge is fatigue in maintenance. Throughout the world, the rules
addressing fatigue are not strict. There are exceptions, usually due to
national labor law. That leaves the responsibility of addressing fatigue
challenges with companies, labor organizations and individuals.

A strict regulation regarding duty time may not be the best solution for
everyone. The issue crosses a variety of domains, including but not
limited to science, health, fitness for duty and safety, plus
significant corporate and personal economic issues. One size does not
fit all.

The industry must not wait for regulators to issue a mandate. Tools are
available that organizations can use to assess the potential impact of
their scheduling practices on fatigue and performance. Industry must
step up to professional reviews of scheduling patterns, managing shifts
and tracking duty time, plus beginning to recognize fatigue as a valid
reason to miss or stop work.

Additional opportunities for improvement, depending on company and
country, may include the following: increased use of error reporting
system data; application of systems and data to cost-justify human
factors programs; improved training for human factors trainers; improved
systems for technical documentation; and more. The international
movement towards a formal SMS environment is a step in the right
direction. It is critical that SMS never loses focus on the most
important link in the safety chain, the human.

*William B. Johnson is chief scientific technical advisor, human factors
in aircraft maintenance systems, FAA, and Carla Hackworth is an
engineering research psychologist, FAA.*

1.  Nearly 1,500 safety professionals worldwide contributed to these
    surveys. The research was a joint effort of the FAA Civil Aerospace
    Medical Institute (CAMI) at the Mike Monroney Aeronautical
    Institute, Oklahoma City, Oklahoma, U.S., and the Maintenance
    Division of the Flight Standards Service, Washington, D.C. Flight
    Standards participants were John J. Hiles and David Cann. CAMI team
    participants were Kali Holcomb, Joy Banks, Melanie Dennis and David
    Schroeder.

2.  Hackworth, C., Holcomb, K., Dennis, M., Goldman, S., Bates, C.,
    Schroeder, D., Johnson, W. (2007a). Survey of Maintenance Human
    Factors Programs Across the World. *The International Journal of
    Applied Aviation Studies*, Volume 7, Number 2, 212--31.

3.  Hackworth, C., Holcomb, K., Dennis, M., Goldman, S., Bates, C.,
    Schroeder, D., Johnson, W. (2007b). *An International Survey of
    Maintenance Human Factors Programs* (Report No. 07/25). Oklahoma
    City, Oklahoma: FAA Civil Aerospace Medical Institute.

4.  Hackworth, C.A., Banks, J.O., Holcomb, K.A., Johnson, W.B., Hiles,
    J.J. (2007c). *Aviation Safety Inspectors' (ASIs) Maintenance Human
    Factors Survey,* (Memorandum Internal FAA Report). Oklahoma City,
    OK: FAA Civil Aerospace Medical Institute.

5.  National Transportation Safety Board (2006). Most Wanted
    Transportation Safety Improvements Federal Issues. Aviation: Reduce
    Accidents and Incidents Caused by Human Fatigue.
    [\<]{.underline}<http://www.ntsb.gov/recs/mostwanted/aviation_reduce_acc_inc_humanfatig.htm>[\>]{.underline}

6.  Human factors manuals are available at
    \<[www.hfskyway.com](http://www.hfskyway.com/)\>.