- Email: [email protected]
Improving aircraft safety and reliability by aircraft maintenance technician training
Accepted Manuscript Improving aircraft safety and reliability by aircraft maintenance technician training
Serdar Dalkilic PII: DOI: Reference:
S1350-6307(16)30883-4 doi: 10.1016/j.engfailanal.2017.06.008 EFA 3173
To appear in:
Engineering Failure Analysis
Received date: Revised date: Accepted date:
1 October 2016 20 May 2017 1 June 2017
Please cite this article as: Serdar Dalkilic , Improving aircraft safety and reliability by aircraft maintenance technician training, Engineering Failure Analysis (2017), doi: 10.1016/j.engfailanal.2017.06.008
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Improving Aircraft Safety and Reliability by Aircraft Maintenance Technician Training Serdar Dalkilic Anadolu University Faculty of Aeronautics and Astronautics, Eskisehir, Turkey Currently working at Higher Colleges of Technology, Aviation Maintenance Engineering Department, Abu Dhabi Men’s College, UAE e-mail: [email protected]
PT
Abstract
Aircraft maintenance is one of the primary causes or contributing factors in aircraft
RI
accidents. It is clear that proper training of Aircraft Maintenance Technicians (AMTs) will
SC
avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation and provide recovery of the increasing demand to qualified AMTs for sustainability of the
NU
market growth. In this study, European Safety Agency (EASA) based AMT licencing system in EU states (and non-EU states implementing EASA rules) has been analysed and a training model developed in accordance with EASA Part-66 requirements and delivered by e-learning
MA
methods has been introduced. The analysis of the licencing process based on EASA regulations showed that this process was based on the candidate’s demonstration of
D
knowledge and acquisition of experience. The required experience depends on the training background of the candidate. Field exercise showed that developed e-learning training model,
PT E
which overcomes the disadvantages of traditional face to face training models, succeeded to improve the attendees’ theoretical knowledge level and when combined with the practical trainings given to AMT candidates in maintenance organisations during their experience
CE
periods, will be very successful in improving safety and reliability in aviation maintenance
Keywords
AC
operations.
Aircraft Maintenance, Safety, Reliability, Training
Introduction The growing complexity of equipment and systems, as well as the rapidly increasing cost incurred by loss of operation as a consequence of failures, has brought to the forefront the aspects of reliability, maintainability, availability, and safety. The expectation today is that complex equipment and systems are not only free from defects and systematic failures at time t =0 (when they are put into operation), but also perform the required function failure free for
ACCEPTED MANUSCRIPT a stated time interval [1]. In case of aviation, this interval, i.e. the service life of an aircraft may be some decades. It is evident that reliability will deteriorate by the time. However, it must be prevented that reliability decreases beyond a critical level and safety is compromised. To provide this, systems and components must be better designed to achieve a higher inherent reliability and appropriate maintenance actions must be performed. Figure 1 shows that inherent or built-in reliability (Ri) decreases by the time but a decrease beyond a critical reliability (Rc) level must
PT
be prevented. Hence, preventive maintenance is performed at times t1 and t2. Nevertheless, it is possible that reliability may decrease to a level well beyond the critical reliability at any
RI
time (t3 in Figure 1). Failures, accidents and incidents are some examples of this situation.
SC
Reliability is restored to inherent reliability level by means of a corrective maintenance
PT E
D
MA
NU
action.
CE
Figure 1. Reliability versus time
Figure 1 clearly implies that, in the aviation industry, the lack of maintenance or in the
AC
case of improper maintenance, any component which deteriorates due to use or environmental conditions will fail and compromise whole aircraft airworthiness and safety. Furthermore, this kind of discrepancy compromise the dispatch reliability of the operator resulting with flight delays and cancellations which in turn drives many direct and latent costs, such as loss of reputation and competitiveness. Above all; maintenance is not only an operational requirement, but also it is a legal obligation. International Civil Aviation Organization (ICAO), European Aviation Safety Agency (EASA) and Federal Aviation Administration (FAA) all emphasize that it is one of the responsibilities of an air operator to ensure that maintenance of its airplanes is performed for continuing airworthiness.
ACCEPTED MANUSCRIPT There are many agents threating aviation safety. Different from others, maintenance errors can be more difficult to detect, and have potential to affect the safe operation of aircraft for longer periods of time. Technical/ maintenance failure emerged as the leading cause of airline accidents and fatalities, surpassing controlled flight into terrain (CFIT), which had previously been the predominant cause of airline accidents. US National Transport Safety Board (NTSB) reported that deficient maintenance has been implicated in 7 of 14 (50%) recent airline accidents [2]. NTSB also stated that maintenance problems are on the increase
PT
or that, as improvements are made in aircraft design, pilot training, ATC etc., the proportion of accidents attributable to these factors is lower and the proportion attributable to poor
RI
maintenance consequently higher [3].
SC
There are many studies investigating the effects of maintenance on aviation safety and reliability. Many accident models suggest that accidents result from a combination of factors
NU
and these can be classified into immediate causes and underlying or root causes, or into active and latent failures (i.g. improperly trained maintenance technicians) [4]. These studies include
suggestions to reduce these errors.
MA
the contribution of maintenance errors to accidents, costs of maintenance errors and
In 2007 EASA analysed all worldwide commercial aircraft accidents from 1990 to
D
2006 and found that in 8% of the accidents, the primary cause was maintenance. [5]. International Air Transport Association (IATA) safety report concludes that maintenance
PT E
events counted as an average of 10% of threats that led to 432 aircraft accidents between 2009 and 2013. Maintenance operations including training systems were found to be a latent condition for 8% of the 338 non-fatal accidents in the same time period [6]. A study focused
CE
on the primary cause of hull accidents and did not include contributing factors which involve more than one category. The study concludes that flight crew errors comprised the largest
AC
percentage of primary cause factors, but maintenance factors were a very considerable 6%, and takes the third rank [7]. From 2003 to 2008 IATA found that incorrectly performed maintenance was causal (either as a primary cause or an initial link in the accident chain) in 20-40% of the worldwide aircraft accidents for those years [8]. Boeing studied 232 commercial jet aircraft accidents and looked at the data from the perspective of accident prevention opportunities and found that 20% of the accidents contained maintenance or inspection action [3]. Similarly, Boeing and Airline Transport Association (ATA) found that maintenance was one factor that contributed to 39 of 264 (15%) commercial jet aircraft hull loss accidents [9].
ACCEPTED MANUSCRIPT According to UK Civil Aviation Authority (CAA), 10% of events recorded under the requirements of CAA’s Mandatory Occurrence Reporting (MOR) scheme, are maintenance related. Among 3982 maintenance related MORs for the period of 1996 to 2006, 51.1% were attributed to incorrect maintenance actions, 26.2% to ineffective maintenance control and 20.7% to incomplete maintenance [10]. Another study focused on the fatality of maintenance related accidents. They found that between 1999 and 2008, 26.7% of all fatal accidents were maintenance related. Further,
PT
while only 4.4% were fatal, 28.6% of maintenance accidents were fatal. That is, a maintenance related accident was 6.5 times more likely to involve fatalities than accidents in
RI
general. In the same time period maintenance was linked to 27.4 of all aviation fatalities.
SC
Recalling that maintenance was involved in only 4.1 of accidents, this number suggests that maintenance related accidents do tend to have a slightly higher fatality rate than accidents
NU
overall [4].
Maintenance errors have not only the safety consequences but also economic losses and they are very costly to aviation industry. Maintenance errors may require air turn backs,
MA
delays in aircraft availability, gate returns, in-flight shut downs, maintenance rework, damage to maintenance equipment and injury to maintenance personnel. These errors are usually
D
latent errors and have a delayed effect and are responsible for an estimated 20-30% of engine and equipment in-flight shut downs [11]. It is estimated that maintenance errors cause 20-30%
PT E
of engine in-flight shutdowns at a cost of USD 500,000 per shutdown, 50% of flight delays and flight cancellations due to engine problems at a cost of USD 9,000 per hour and USD 66,000 per cancellation respectively. In the case of a large aircraft such as a Boeing 747, a
CE
flight cancellation can cost the airline around USD 140,000, while a delay at the gate can cost an average of USD 17,000 per hour. One airline estimated between USD 75-100 million per
AC
year is wasted on error [2, 7, 9, 12]. As a consequence of global economic growth and increasing urbanization, air travel remains a growing market. The two biggest commercial aircraft manufacturers Boeing and Airbus market research between 2012 and 2031 predicts a continuing growth. For example, 20-year world annual traffic growth of 4.7% is forecast by Airbus [13] and 5.0% by Boeing [14]. The number of passengers travelled by air was above 3 billion in 2011 and is forecast to be above 7.5 billion in 2031. Passenger aircraft fleet (only commercial aircraft with seats > 100) was 15,555 in 2011 and is predicted to be 32,551 in 2031 which means an increase of 109%. [13]. Boeing reports that aircraft fleet including regional jets and freighters was 19,890
ACCEPTED MANUSCRIPT in 2011 and is forecast to be 39,780 in 2031. 34.000 new aircraft deliveries between 20122031 are predicted. New airplane deliveries by regions are summarized in the table 1 below.
Table 1. New airplane deliveries by regions [14] Europe 200 1,440 5,800 320 7,760
Middle East 190 1,100 1,060 20 2,370
Latin America 0 340 2,080 90 2,510
CIS
Africa
PT
North America 40 1,320 5,040 890 7,290
30 250 700 160 1,140
RI
Large Twin aisle Single aisle Regional jets Total
Asia Pacific 320 3,230 7,990 490 12,030
10 270 570 50 900
World 790 7,950 23,240 2,020 34,000
SC
As global economies continue to grow and thousands of new aircraft are delivered during the next 20 years, the demand for personnel to operate these airplanes will be unique.
NU
Boeing projects a need for approximately 601,000 new aircraft maintenance technicians [14].
MA
New technician demand by region has been given in Table 2.
Table 2. New technicians by region [13]
Technicians
Asia Pacific 243,500
Europe 129,700
North America 92,500
D
Regions
Middle East 53,700
Latin America 47,300
CIS
Africa
World
18,100
16,200
601,000
PT E
Meeting this demand will require airplane manufacturers and the commercial aviation industry to rely more heavily on new digital technology to meet the learning requirements of new generation. The growing diversity of aviation personnel also demands highly qualified,
CE
motivated and knowledgeable instructors with cross-cultural and cross-generational skills. Emerging markets that currently recruit maintenance technicians from outside the region will
AC
have to develop a foundation for training qualified personnel from within the local workforce [14]. Reversely, there has been a continuing decline in both the number of people applying to training programs for AMTs and the percentage of program graduates who stay in aviation [15]. ICAO reports that the year over year accident statistics indicate an increase in the overall number of accidents as well as the accident rate. The global accident rate involving scheduled commercial operations increased by 7%, from 2.8 accidents per million departures in 2013 to 3.0 accidents per million departures in 2014 [16]. It is clear that, even though the accident rate remains constant for the next decades, the air traffic growth will result in increased number of accidents and fatalities.
ACCEPTED MANUSCRIPT Many studies conclude that time pressure, lack of technical knowledge and inadequate training were among the most likely reasons for the maintenance errors. Better training is one of the elements that maintenance errors can be managed by. Therefore, a similar event is prevented from occurring in the future, one of the agents leading to major accidents is eliminated and safety and reliability in aviation is improved [2, 12, 17, 18]. Furthermore, the rapid growth of the market and the increased costs lead MRO organizations to employ maintenance staff who are not certified (no AMT License) for performing minor maintenance
PT
tasks. Training of AMTs is more important than ever to improve safety and reliability in
RI
aviation and for a sustainable growth of the market.
SC
Aircraft Maintenance Technician (AMT) Licencing System and Proposed Training Model
NU
In this part of the study EASA based AMT licencing system in EU states (and non-EU states implementing EASA rules) is analysed. This system meets the intent of ICAO Annex I and is not very different from US FAA regulations.
MA
The requirements for initial and continuing airworthiness of aircraft and related products are explained in the European Commission Regulations. Annex I (Part M) to
D
Commission Regulation No. 2042/2003 states that the owner or lessee is responsible for continuing airworthiness of an aircraft and the maintenance organisations need to have
PT E
sufficient aircraft maintenance certifying staff to issue certificates of release to service of an aircraft or a component after maintenance. These maintenance staff must be qualified in accordance with Annex III (Part-66) of the same regulation.
CE
An individual who decided to become an AMT (Aircraft Maintenance Licence holder) must demonstrate by examination, a level of knowledge and must have acquired practical
AC
maintenance experience on operating aircraft. The required experience for applicants with different training backgrounds is listed in Table 3. This experience must be practical and involve maintenance tasks on aircraft.
Table 3. Practical maintenance experience requirement Category/sub-
No previous relevant
Relevant
category
technical training
Training
Part-147 Basic Training
A, B1.2, B1.4, B3
3 years
2 years
1 year
B2, B1.1, B1.3
5 years
3 years
2 years
ACCEPTED MANUSCRIPT Thereafter, a basic Aircraft Maintenance Licence (without aircraft type endorsement) in adequate category/subcategory is issued if the applicant is at least at the age of 18. This basic AML does not alone let its holder to release an aircraft to service in line maintenance or to work as support staff (to perform particular maintenance tasks) in base maintenance. To provide this, the AML holder need to have his/her licence endorsed with the relevant aircraft ratings. For category A, no rating is required. The endorsement of aircraft type rating requires satisfactory completion of aircraft type training. In addition, the endorsement of the first
PT
rating requires completion of On the Job Training (OJT).
Aircraft type training consists of theoretical training and examination plus practical
RI
training and assessment. This training and examinations can only be conducted by
SC
maintenance training organisations approved i.a.w. Annex IV (Part-147) of the regulation. The objective of the OJT is to gain the required competence and experience in performing
NU
safe maintenance and can be conducted under the control of maintenance organisations approved under Annex II (Part 145).
Upon type rating endorsement into the basic AML and receiving a “certification
MA
authorisation” from the Part-145 maintenance organisation, the licence holder becomes a certifying staff to sign certificate of release to service on behalf of the organisation. The
D
minimum age for certifying staff and support staff is 21 years. Organisations involved in the training of aircraft maintenance personnel (certifying
PT E
staff) must be approved i.a.w. Annex IV (Part-147) of the regulation. The organisations fulfilling the facility, personnel and instructional equipment requirements may apply for approval to carry out:
basic training courses to the Part-66 syllabus,
aircraft type/task training courses,
the examinations on behalf of the aviation authority,
AC
CE
the issue of certificates following completion of basic or type training courses and examinations.
Basic training course consists of knowledge training, knowledge examination, practical training and a practical assessment. The duration of basic training courses is given in Table 4. The practical training covers the practical use of common tools and test equipment, the disassembly/assembly of aircraft parts and the participation in maintenance activities. The practical assessment determines whether the student is competent at using tools and
ACCEPTED MANUSCRIPT equipment and working in accordance with technical documents such as maintenance manuals.
Table 4. Basic training course duration in hours A1, A3, A4
A2
B1.1, B1.3, B1.4, B2
B1.2
B3
Duration
800
650
2400
2000
1000
PT
Category
The complete EASA aircraft maintenance licencing system from beginning with
AC
CE
PT E
D
MA
NU
SC
RI
individual’s decision to become an AMT is summarized in Figure 2.
Figure 2. EASA aircraft maintenance licencing system
ACCEPTED MANUSCRIPT In many European countries as well as Turkey, vocational training and education is heavily based on national education system. In this context, this part of the chapter studies the process where 3 candidates in Turkey with different educational backgrounds intending to become an AMT in B1.1 or B2 category. Candidate 1 is a high school graduate with no relevant training. Candidate 2 is a vocational high school graduate and his training is considered as relevant by the aviation authority. Finally, candidate 3 is a high school graduate and wishes to study in a Part-147
PT
approved training organisation (MTO). All candidates are 18 years old (average age of high school graduates). According to EASA training system described above; candidate 1 must
RI
pass examinations and acquire 5 years of experience, candidate 2 must pass examinations and
SC
acquire 3 years of experience while candidate 3 must study for minimum 2400 tuition hours in a Part-147 approved maintenance training organisation, pass examinations and acquire 2 years
NU
of experience. 2400 tuition hours requires approximately 2 years. In Turkey the only MTO approved for category B1.1 and B2 basic training is a University offering a 4 years bachelor’s degree program in aviation maintenance.
MA
Consider that three candidates passed all examinations in the period of experience times. In this case candidate 1 and 2 start to work in a Part-145 maintenance organisation at
D
18 years old and become an AMT at 23 and 21 years old respectively. On the other hand, candidate 3 enters into the industry 4 years later than the others, at 22 years old and becomes
PT E
an AMT at 24 years old. On the other hand, candidates 1 and 2 may complete their type and on the job trainings much earlier than candidate 3. The only weakness of candidate 1 and 2 is that, they have to self-study and may have
CE
difficulties in passing examinations. Furthermore, finding (and funding) appropriate training materials in their language may be an issue.
AC
Above mentioned approved MTO in Turkey accepts 80 students per year and the total number of students to be graduated in the next four years is 444 (information received from the management of the organisation), which is much less than the number required by maintenance organisations. On the other hand, ten vocational schools, which have no Part-147 approval but considered as offering relevant training, are expected to graduate more than 1500 students in the next four years. This case let these students become potential employees for the maintenance organisations. However, their proper training is now much more important not only to support sustainable growth of the aviation market but also to improve the safety and reliability of the aircraft maintained.
ACCEPTED MANUSCRIPT A research study funded by Boeing’s Global Corporate Citizenship program and supported by Turkey’s Ministry of National Education has been initiated to search the means to overcome this issue. The field exercise of the study included 77 teachers from above mentioned vocational schools since improvements in their knowledge levels will result in improvements on the training of thousands of students. In order to assess the initial knowledge level of the participants, a questionnaire including complete EASA Part 66 syllabus for license category B1.1 has been sent to subject
PT
schools. The participants were asked to evaluate their readiness to deliver each Part 66 module, where;
0 means the participant has no background to teach the subject,
1 means the participants needs a refreshment to teach the subject,
2 means the participant has enough knowledge to teach the subject.
SC
RI
NU
An example where scores are arbitrary has been given in Table 4.
MA
Table 4. Self-evaluation of participants’ readiness Module
Sub Module 8.1- Physics of the atmosphere
2
8.2- Aerodynamics
1
D
8- Basic Aerodynamics
Score
PT E
8.3- Theory of flight 8.4- Flight stability and dynamics
0 0
CE
The results of the questionnaire indicated that the participants has no background around 70% of the syllabus, need a refreshment on 20% percent of the syllabus and enough knowledge to teach around 10% of the syllabus. Furthermore a test with multiple choice
AC
questions representing the whole syllabus sent to schools. The test has been prepared by subject matter expert i.a.w. Part 66 requirements where pass-mark is 75%. Minimum score was 26%, maximum score was 72% and mean score was 53. Both the questionnaire and test results demonstrated that the participants of the field exercise can be considered as an AMT candidate with no previous aircraft maintenance training and all course materials have been prepared accordingly. In the context of the project a software applicable to distance education methods has been developed. The web based software includes a virtual classroom platform where the instructors uploaded their course materials. The course materials developed by the academic
ACCEPTED MANUSCRIPT staff of the above mentioned Part-147 MTO are not limited to some texts; conversely there is an audio visual media such as schematics, animations, slights etc. Total of 253 training packages has been prepared where a package includes course notes in text format, audiovisual training material in video format and an end of chapter quiz (Fig. 3). An introduction session has been offered to participants to familiarize them with the system and interface. The participants, upon signing in to virtual classroom, are able to reach all the course materials. At the end of each sub-module a quiz was introduced to let the participant self-assess and to
PT E
D
MA
NU
SC
RI
PT
provide progression data to the instructor through a learning management system.
Figure 3. Example of a training package (original interface in Turkish language) The training model have been designed to cover certain learning outcomes as required
CE
by EASA Part-66. At the end of the complete training the attendant will; know the theory of the subject and interrelationships with other subjects,
be able to give a detailed description of the subject using theoretical fundamentals and
AC
specific examples,
understand and be able to use mathematical formulae related to the subject,
be able to read, understand and prepare sketches, simple drawings and schematics describing the subject,
be able to apply his knowledge in a practical manner using manufacturer’s instructions,
be able to interpret results from various sources and measurements and apply corrective action where appropriate.
ACCEPTED MANUSCRIPT During the project, the participants received some practical trainings and assessments in an Aircraft Maintenance Organisation. A post training test was conducted to assess if all these learning outcomes are attained and a questionnaire was send to participants to receive their responses about training. Minimum score was 70%, maximum score was 96% and mean score was 80.
Results and Discussion
PT
Aircraft maintenance is one of the primary causes or contributing factors in aircraft accidents. The growth of aviation market leading to increase the number of flights and
RI
number of passengers travelled, may result in increasing number of accidents and fatalities
SC
even though the accident rate remains constant. It is clear that proper training of AMTs will avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation
NU
and provide recovery of the increasing demand to qualified AMTs for sustainability of the market growth.
AMT training is governed by international (IATA) and regional or local (EASA and
MA
FAA) regulations. But different training models can be developed in the frame of these regulations. In this paper, AMT licencing process in EU region (and non-EU states
D
implementing EASA rules) is analysed. This process is based on the candidate’s demonstration of knowledge and acquisition of experience. The required experience depends
PT E
on the training background of the candidate. The graduates of Part-147 approved MTOs need to have minimum experience but they need extra time for training and this delays their entrance into the market. The candidates that have no approved aircraft maintenance training
CE
background needs more experience, have to self-study for the examinations but enter to the market earlier and complete their type and on the job trainings.
AC
Furthermore, the difficulties and costs to fulfil the Part-147 requirements limit the number of Part-147 MTOs and their graduates. In many countries like Turkey, AMT training heavily relies on national education system which increases the training duration. In this case, maintenance organisations start to employ staff without any approved aircraft maintenance training background. These staffs are entering to knowledge examinations while acquiring the required experience in the maintenance organisations. Now their training is much more important to make them ready for the examinations, to make some behavioural changes and to improve their awareness for the safety and reliability of the aircraft that they are working on. On the other hand, companies may not prefer to organize a training course for their employees since they will lose labour while the employees are attending to a course rather
ACCEPTED MANUSCRIPT than working and an outsourced training will have a cost to the company. This will lead the candidate to self-study and in this case he/she may face difficulties in finding appropriate training materials in own language. Funding of the training materials would be another demotivating issue. The complete EASA Part 66 syllabus for A, B1.1 and B2 category AMT licenses have been transferred to developed distance education platform. The developed software and the training model showed that AMT trainings can be delivered to public by e-learning methods.
PT
Costly times of people and companies/public institutions will not be spent by traditional face to face training. People will be able to receive their own required training whenever and
RI
wherever they want.
SC
Field exercise covered 77 teachers from vocational schools offering aircraft maintenance training and showed that developed e-learning training model succeeded to
NU
improve their theoretical knowledge level. All participants agreed that the training model gave them flexibility to decide when to and how much to study any subject. They also emphasized that diversity of the training materials was very useful. For example the material in text
MA
format was very suitable in an office environment while audio-visual material let the participants to study using their smart phones on the way to office and home. The participants
D
were satisfied with the navigating in the web based system, content delivery and interface. They implied that practical trainings in between theoretical training was very useful to
PT E
consolidate the theoretical knowledge gained but the periods could be longer. This training model can cover the students of this kind of schools, the employees of maintenance organisations preparing for knowledge examinations and shortly anybody aiming
CE
to become an AMT.
This kind of training model developed in accordance with Part-66 requirements and
AC
delivered by distance education (e-learning) methods would be very successful when combined with the practical trainings given to candidates in maintenance organisations during their experience periods.
Conclusions The literature search in the scope of this paper points the importance of training of aircraft maintenance technicians (AMTs) to reduce the number of accidents due to maintenance errors. It is emphasized that training of AMTs is vital to reduce failures, improve safety and reliability in aviation and recovery of the increasing demand to qualified AMTs in the growing aviation market.
ACCEPTED MANUSCRIPT The analysis of the licencing process based on European Aviation Safety Agency regulations concludes that this process is based on the candidate’s demonstration of knowledge and acquisition of experience. The required experience depends on the training background of the candidate. The graduates of Part-147 approved MTOs need to have minimum experience but they need extra time for training and this delays their entrance into the market. The candidates that have no approved aircraft maintenance training background needs more experience, have to self-study for the examinations but enter to the market earlier
PT
and complete their type and on the job trainings.
In countries where AMT training heavily relies on national education system, the
RI
training duration is increased and maintenance organisations start to employ staff without any
SC
approved aircraft maintenance training background.
This paper offers a training model developed in accordance with Part-66 requirements
NU
and delivered by distance education (e-learning) methods to overcome the disadvantages of face to face training. It is concluded that this model when combined with the practical trainings given to AMT candidates in maintenance organisations during their experience
MA
periods, will be very successful in improving safety and reliability in aviation maintenance
D
operations.
Acknowledgements
PT E
This study was supported by Global Corporate Citizenship program of The Boeing Company
References
CE
under grant number 16117843.
1. Birolini, A., Reliability Engineering, Theory and Practice, Springer, Berlin, 2006.
AC
2. Hobbs A, An overview of human factors in aviation maintenance. Australian Transport Safety Bureau; December, 2008. ISBN 978-1-921490-93-4 3. Safety Regulation Group, CAA, 2003, CAP 716 Aviation maintenance human factors (EASA /JAR145 Approved Organisations), http://www.caa.co.uk/docs/33/CAP716.pdf (accessed 09.10.15) 4. Marais K.B., Robichaud M.R., Analysis of trends in aviation maintenance risk: An empirical approach, Reliability Engineering and System Safety 106 (2012) 104-118. 5. EASA, Guidance on Safety Hazard Identification, 2009 http://www.easa.europa.eu/essi/ documents/ECASTSMSWG-GuidanceonHazardIdentification.pdf (accessed 09.10.15)
ACCEPTED MANUSCRIPT 6. Safety Report 2013, International Air Transport Association, Montreal, ISBN 978-92-9252349-7. 7. Federal Aviation Administration, 2014, Introduction to maintenance error analysis, http://www.faa.gov/about/initiatives/maintenance_hf/library/documents/media/hfacs/1_introduction.pdf (accessed 09.10.15) 8. IATA Safety Report, 2013 http://www.iata.org/publications/Documents/iata-safety-report2013.pdf (accessed 09.10.15)
PT
9. Rankin W., Hibit R., Allen J. and Sargent R., Development and evaluation of the Maintenance Error Decision Aid (MEDA). International Journal of Industrial Ergonomics 26
RI
(2000) 261-276.
SC
10. Safety Regulation Group, CAA, 2009, CAP 2009/05, Aircraft maintenance incident analysis, http://www.caa.co.uk/docs/33/2009_05.pdf (accessed 09.10.15)
NU
11. Liang G.F. et-al, Preventing human errors in aviation maintenance using an on-line maintenance assistance platform, International Journal of Industrial Ergonomics 40 (2010) 356-367.
MA
12. Ranking W, Maintenance error decision aid investigation process, 2007 Boeing. http://www.boeing.com/commercial/aeromagazine/articles/qtr_2_07/AERO_Q207_article3.p
D
df (accessed 09.10.15)
13. Global market forecast 2012-2031. (2012). Cedex, France: Airbus S.A.S.
PT E
14. Current market outlook 2012-2031. (2012). Seattle, USA: The Boeing Company. 15. Gramopadhye A.K., Drury C.G., Human factors in aviation maintenance: how we got to where we are, International Journal of Industrial Ergonomics 26 (2000) 125-132.
9252-349-7.
CE
16. Safety Report 2015, International Air Transport Association, Montreal, ISBN 978-92-
AC
17. Schreiber F., Human performance error management: Airbus maintenance briefing notes; 2007.http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafety Lib_-MAINT-HUM_PER- SEQ02.pdf (accessed 09.10.15) 18. Health and Safety Executive, Inspectors Toolkit: Human Factors in the management of major accident hazards, 2005, http://www.hse.gov.uk/humanfactors/topics/toolkitintro.pdf (accessed 09.10.15)
ACCEPTED MANUSCRIPT Serdar Dalkilic Anadolu University Faculty of Aeronautics and Astronautics, Department of Airframe and Powerplant Maintenance, 26470 Eskisehir, Turkey e-mail: [email protected] Oct 1st, 2016
Dear Editor,
PT
Please find below the highlights of my manuscript:
Aircraft maintenance is one of the primary causes or contributing factors in aircraft
Proper training of AMTs will avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation.
Analysed AMT process is based on the candidate’s demonstration of knowledge and
NU
acquisition of experience.
MA
Proposed e-learning training model would be very successful when combined with the practical trainings given to candidates in maintenance organisations during their
Yours sincerely,
PT E
Serdar Dalkılıç, PhD.
D
experience periods.
Assistant Professor, Faculty of Aeronautics and Astronautics
CE
Department of Airframe and Powerplant Maintenance Anadolu University
AC
SC
RI
accidents.
Serdar Dalkilic PII: DOI: Reference:
S1350-6307(16)30883-4 doi: 10.1016/j.engfailanal.2017.06.008 EFA 3173
To appear in:
Engineering Failure Analysis
Received date: Revised date: Accepted date:
1 October 2016 20 May 2017 1 June 2017
Please cite this article as: Serdar Dalkilic , Improving aircraft safety and reliability by aircraft maintenance technician training, Engineering Failure Analysis (2017), doi: 10.1016/j.engfailanal.2017.06.008
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Improving Aircraft Safety and Reliability by Aircraft Maintenance Technician Training Serdar Dalkilic Anadolu University Faculty of Aeronautics and Astronautics, Eskisehir, Turkey Currently working at Higher Colleges of Technology, Aviation Maintenance Engineering Department, Abu Dhabi Men’s College, UAE e-mail: [email protected]
PT
Abstract
Aircraft maintenance is one of the primary causes or contributing factors in aircraft
RI
accidents. It is clear that proper training of Aircraft Maintenance Technicians (AMTs) will
SC
avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation and provide recovery of the increasing demand to qualified AMTs for sustainability of the
NU
market growth. In this study, European Safety Agency (EASA) based AMT licencing system in EU states (and non-EU states implementing EASA rules) has been analysed and a training model developed in accordance with EASA Part-66 requirements and delivered by e-learning
MA
methods has been introduced. The analysis of the licencing process based on EASA regulations showed that this process was based on the candidate’s demonstration of
D
knowledge and acquisition of experience. The required experience depends on the training background of the candidate. Field exercise showed that developed e-learning training model,
PT E
which overcomes the disadvantages of traditional face to face training models, succeeded to improve the attendees’ theoretical knowledge level and when combined with the practical trainings given to AMT candidates in maintenance organisations during their experience
CE
periods, will be very successful in improving safety and reliability in aviation maintenance
Keywords
AC
operations.
Aircraft Maintenance, Safety, Reliability, Training
Introduction The growing complexity of equipment and systems, as well as the rapidly increasing cost incurred by loss of operation as a consequence of failures, has brought to the forefront the aspects of reliability, maintainability, availability, and safety. The expectation today is that complex equipment and systems are not only free from defects and systematic failures at time t =0 (when they are put into operation), but also perform the required function failure free for
ACCEPTED MANUSCRIPT a stated time interval [1]. In case of aviation, this interval, i.e. the service life of an aircraft may be some decades. It is evident that reliability will deteriorate by the time. However, it must be prevented that reliability decreases beyond a critical level and safety is compromised. To provide this, systems and components must be better designed to achieve a higher inherent reliability and appropriate maintenance actions must be performed. Figure 1 shows that inherent or built-in reliability (Ri) decreases by the time but a decrease beyond a critical reliability (Rc) level must
PT
be prevented. Hence, preventive maintenance is performed at times t1 and t2. Nevertheless, it is possible that reliability may decrease to a level well beyond the critical reliability at any
RI
time (t3 in Figure 1). Failures, accidents and incidents are some examples of this situation.
SC
Reliability is restored to inherent reliability level by means of a corrective maintenance
PT E
D
MA
NU
action.
CE
Figure 1. Reliability versus time
Figure 1 clearly implies that, in the aviation industry, the lack of maintenance or in the
AC
case of improper maintenance, any component which deteriorates due to use or environmental conditions will fail and compromise whole aircraft airworthiness and safety. Furthermore, this kind of discrepancy compromise the dispatch reliability of the operator resulting with flight delays and cancellations which in turn drives many direct and latent costs, such as loss of reputation and competitiveness. Above all; maintenance is not only an operational requirement, but also it is a legal obligation. International Civil Aviation Organization (ICAO), European Aviation Safety Agency (EASA) and Federal Aviation Administration (FAA) all emphasize that it is one of the responsibilities of an air operator to ensure that maintenance of its airplanes is performed for continuing airworthiness.
ACCEPTED MANUSCRIPT There are many agents threating aviation safety. Different from others, maintenance errors can be more difficult to detect, and have potential to affect the safe operation of aircraft for longer periods of time. Technical/ maintenance failure emerged as the leading cause of airline accidents and fatalities, surpassing controlled flight into terrain (CFIT), which had previously been the predominant cause of airline accidents. US National Transport Safety Board (NTSB) reported that deficient maintenance has been implicated in 7 of 14 (50%) recent airline accidents [2]. NTSB also stated that maintenance problems are on the increase
PT
or that, as improvements are made in aircraft design, pilot training, ATC etc., the proportion of accidents attributable to these factors is lower and the proportion attributable to poor
RI
maintenance consequently higher [3].
SC
There are many studies investigating the effects of maintenance on aviation safety and reliability. Many accident models suggest that accidents result from a combination of factors
NU
and these can be classified into immediate causes and underlying or root causes, or into active and latent failures (i.g. improperly trained maintenance technicians) [4]. These studies include
suggestions to reduce these errors.
MA
the contribution of maintenance errors to accidents, costs of maintenance errors and
In 2007 EASA analysed all worldwide commercial aircraft accidents from 1990 to
D
2006 and found that in 8% of the accidents, the primary cause was maintenance. [5]. International Air Transport Association (IATA) safety report concludes that maintenance
PT E
events counted as an average of 10% of threats that led to 432 aircraft accidents between 2009 and 2013. Maintenance operations including training systems were found to be a latent condition for 8% of the 338 non-fatal accidents in the same time period [6]. A study focused
CE
on the primary cause of hull accidents and did not include contributing factors which involve more than one category. The study concludes that flight crew errors comprised the largest
AC
percentage of primary cause factors, but maintenance factors were a very considerable 6%, and takes the third rank [7]. From 2003 to 2008 IATA found that incorrectly performed maintenance was causal (either as a primary cause or an initial link in the accident chain) in 20-40% of the worldwide aircraft accidents for those years [8]. Boeing studied 232 commercial jet aircraft accidents and looked at the data from the perspective of accident prevention opportunities and found that 20% of the accidents contained maintenance or inspection action [3]. Similarly, Boeing and Airline Transport Association (ATA) found that maintenance was one factor that contributed to 39 of 264 (15%) commercial jet aircraft hull loss accidents [9].
ACCEPTED MANUSCRIPT According to UK Civil Aviation Authority (CAA), 10% of events recorded under the requirements of CAA’s Mandatory Occurrence Reporting (MOR) scheme, are maintenance related. Among 3982 maintenance related MORs for the period of 1996 to 2006, 51.1% were attributed to incorrect maintenance actions, 26.2% to ineffective maintenance control and 20.7% to incomplete maintenance [10]. Another study focused on the fatality of maintenance related accidents. They found that between 1999 and 2008, 26.7% of all fatal accidents were maintenance related. Further,
PT
while only 4.4% were fatal, 28.6% of maintenance accidents were fatal. That is, a maintenance related accident was 6.5 times more likely to involve fatalities than accidents in
RI
general. In the same time period maintenance was linked to 27.4 of all aviation fatalities.
SC
Recalling that maintenance was involved in only 4.1 of accidents, this number suggests that maintenance related accidents do tend to have a slightly higher fatality rate than accidents
NU
overall [4].
Maintenance errors have not only the safety consequences but also economic losses and they are very costly to aviation industry. Maintenance errors may require air turn backs,
MA
delays in aircraft availability, gate returns, in-flight shut downs, maintenance rework, damage to maintenance equipment and injury to maintenance personnel. These errors are usually
D
latent errors and have a delayed effect and are responsible for an estimated 20-30% of engine and equipment in-flight shut downs [11]. It is estimated that maintenance errors cause 20-30%
PT E
of engine in-flight shutdowns at a cost of USD 500,000 per shutdown, 50% of flight delays and flight cancellations due to engine problems at a cost of USD 9,000 per hour and USD 66,000 per cancellation respectively. In the case of a large aircraft such as a Boeing 747, a
CE
flight cancellation can cost the airline around USD 140,000, while a delay at the gate can cost an average of USD 17,000 per hour. One airline estimated between USD 75-100 million per
AC
year is wasted on error [2, 7, 9, 12]. As a consequence of global economic growth and increasing urbanization, air travel remains a growing market. The two biggest commercial aircraft manufacturers Boeing and Airbus market research between 2012 and 2031 predicts a continuing growth. For example, 20-year world annual traffic growth of 4.7% is forecast by Airbus [13] and 5.0% by Boeing [14]. The number of passengers travelled by air was above 3 billion in 2011 and is forecast to be above 7.5 billion in 2031. Passenger aircraft fleet (only commercial aircraft with seats > 100) was 15,555 in 2011 and is predicted to be 32,551 in 2031 which means an increase of 109%. [13]. Boeing reports that aircraft fleet including regional jets and freighters was 19,890
ACCEPTED MANUSCRIPT in 2011 and is forecast to be 39,780 in 2031. 34.000 new aircraft deliveries between 20122031 are predicted. New airplane deliveries by regions are summarized in the table 1 below.
Table 1. New airplane deliveries by regions [14] Europe 200 1,440 5,800 320 7,760
Middle East 190 1,100 1,060 20 2,370
Latin America 0 340 2,080 90 2,510
CIS
Africa
PT
North America 40 1,320 5,040 890 7,290
30 250 700 160 1,140
RI
Large Twin aisle Single aisle Regional jets Total
Asia Pacific 320 3,230 7,990 490 12,030
10 270 570 50 900
World 790 7,950 23,240 2,020 34,000
SC
As global economies continue to grow and thousands of new aircraft are delivered during the next 20 years, the demand for personnel to operate these airplanes will be unique.
NU
Boeing projects a need for approximately 601,000 new aircraft maintenance technicians [14].
MA
New technician demand by region has been given in Table 2.
Table 2. New technicians by region [13]
Technicians
Asia Pacific 243,500
Europe 129,700
North America 92,500
D
Regions
Middle East 53,700
Latin America 47,300
CIS
Africa
World
18,100
16,200
601,000
PT E
Meeting this demand will require airplane manufacturers and the commercial aviation industry to rely more heavily on new digital technology to meet the learning requirements of new generation. The growing diversity of aviation personnel also demands highly qualified,
CE
motivated and knowledgeable instructors with cross-cultural and cross-generational skills. Emerging markets that currently recruit maintenance technicians from outside the region will
AC
have to develop a foundation for training qualified personnel from within the local workforce [14]. Reversely, there has been a continuing decline in both the number of people applying to training programs for AMTs and the percentage of program graduates who stay in aviation [15]. ICAO reports that the year over year accident statistics indicate an increase in the overall number of accidents as well as the accident rate. The global accident rate involving scheduled commercial operations increased by 7%, from 2.8 accidents per million departures in 2013 to 3.0 accidents per million departures in 2014 [16]. It is clear that, even though the accident rate remains constant for the next decades, the air traffic growth will result in increased number of accidents and fatalities.
ACCEPTED MANUSCRIPT Many studies conclude that time pressure, lack of technical knowledge and inadequate training were among the most likely reasons for the maintenance errors. Better training is one of the elements that maintenance errors can be managed by. Therefore, a similar event is prevented from occurring in the future, one of the agents leading to major accidents is eliminated and safety and reliability in aviation is improved [2, 12, 17, 18]. Furthermore, the rapid growth of the market and the increased costs lead MRO organizations to employ maintenance staff who are not certified (no AMT License) for performing minor maintenance
PT
tasks. Training of AMTs is more important than ever to improve safety and reliability in
RI
aviation and for a sustainable growth of the market.
SC
Aircraft Maintenance Technician (AMT) Licencing System and Proposed Training Model
NU
In this part of the study EASA based AMT licencing system in EU states (and non-EU states implementing EASA rules) is analysed. This system meets the intent of ICAO Annex I and is not very different from US FAA regulations.
MA
The requirements for initial and continuing airworthiness of aircraft and related products are explained in the European Commission Regulations. Annex I (Part M) to
D
Commission Regulation No. 2042/2003 states that the owner or lessee is responsible for continuing airworthiness of an aircraft and the maintenance organisations need to have
PT E
sufficient aircraft maintenance certifying staff to issue certificates of release to service of an aircraft or a component after maintenance. These maintenance staff must be qualified in accordance with Annex III (Part-66) of the same regulation.
CE
An individual who decided to become an AMT (Aircraft Maintenance Licence holder) must demonstrate by examination, a level of knowledge and must have acquired practical
AC
maintenance experience on operating aircraft. The required experience for applicants with different training backgrounds is listed in Table 3. This experience must be practical and involve maintenance tasks on aircraft.
Table 3. Practical maintenance experience requirement Category/sub-
No previous relevant
Relevant
category
technical training
Training
Part-147 Basic Training
A, B1.2, B1.4, B3
3 years
2 years
1 year
B2, B1.1, B1.3
5 years
3 years
2 years
ACCEPTED MANUSCRIPT Thereafter, a basic Aircraft Maintenance Licence (without aircraft type endorsement) in adequate category/subcategory is issued if the applicant is at least at the age of 18. This basic AML does not alone let its holder to release an aircraft to service in line maintenance or to work as support staff (to perform particular maintenance tasks) in base maintenance. To provide this, the AML holder need to have his/her licence endorsed with the relevant aircraft ratings. For category A, no rating is required. The endorsement of aircraft type rating requires satisfactory completion of aircraft type training. In addition, the endorsement of the first
PT
rating requires completion of On the Job Training (OJT).
Aircraft type training consists of theoretical training and examination plus practical
RI
training and assessment. This training and examinations can only be conducted by
SC
maintenance training organisations approved i.a.w. Annex IV (Part-147) of the regulation. The objective of the OJT is to gain the required competence and experience in performing
NU
safe maintenance and can be conducted under the control of maintenance organisations approved under Annex II (Part 145).
Upon type rating endorsement into the basic AML and receiving a “certification
MA
authorisation” from the Part-145 maintenance organisation, the licence holder becomes a certifying staff to sign certificate of release to service on behalf of the organisation. The
D
minimum age for certifying staff and support staff is 21 years. Organisations involved in the training of aircraft maintenance personnel (certifying
PT E
staff) must be approved i.a.w. Annex IV (Part-147) of the regulation. The organisations fulfilling the facility, personnel and instructional equipment requirements may apply for approval to carry out:
basic training courses to the Part-66 syllabus,
aircraft type/task training courses,
the examinations on behalf of the aviation authority,
AC
CE
the issue of certificates following completion of basic or type training courses and examinations.
Basic training course consists of knowledge training, knowledge examination, practical training and a practical assessment. The duration of basic training courses is given in Table 4. The practical training covers the practical use of common tools and test equipment, the disassembly/assembly of aircraft parts and the participation in maintenance activities. The practical assessment determines whether the student is competent at using tools and
ACCEPTED MANUSCRIPT equipment and working in accordance with technical documents such as maintenance manuals.
Table 4. Basic training course duration in hours A1, A3, A4
A2
B1.1, B1.3, B1.4, B2
B1.2
B3
Duration
800
650
2400
2000
1000
PT
Category
The complete EASA aircraft maintenance licencing system from beginning with
AC
CE
PT E
D
MA
NU
SC
RI
individual’s decision to become an AMT is summarized in Figure 2.
Figure 2. EASA aircraft maintenance licencing system
ACCEPTED MANUSCRIPT In many European countries as well as Turkey, vocational training and education is heavily based on national education system. In this context, this part of the chapter studies the process where 3 candidates in Turkey with different educational backgrounds intending to become an AMT in B1.1 or B2 category. Candidate 1 is a high school graduate with no relevant training. Candidate 2 is a vocational high school graduate and his training is considered as relevant by the aviation authority. Finally, candidate 3 is a high school graduate and wishes to study in a Part-147
PT
approved training organisation (MTO). All candidates are 18 years old (average age of high school graduates). According to EASA training system described above; candidate 1 must
RI
pass examinations and acquire 5 years of experience, candidate 2 must pass examinations and
SC
acquire 3 years of experience while candidate 3 must study for minimum 2400 tuition hours in a Part-147 approved maintenance training organisation, pass examinations and acquire 2 years
NU
of experience. 2400 tuition hours requires approximately 2 years. In Turkey the only MTO approved for category B1.1 and B2 basic training is a University offering a 4 years bachelor’s degree program in aviation maintenance.
MA
Consider that three candidates passed all examinations in the period of experience times. In this case candidate 1 and 2 start to work in a Part-145 maintenance organisation at
D
18 years old and become an AMT at 23 and 21 years old respectively. On the other hand, candidate 3 enters into the industry 4 years later than the others, at 22 years old and becomes
PT E
an AMT at 24 years old. On the other hand, candidates 1 and 2 may complete their type and on the job trainings much earlier than candidate 3. The only weakness of candidate 1 and 2 is that, they have to self-study and may have
CE
difficulties in passing examinations. Furthermore, finding (and funding) appropriate training materials in their language may be an issue.
AC
Above mentioned approved MTO in Turkey accepts 80 students per year and the total number of students to be graduated in the next four years is 444 (information received from the management of the organisation), which is much less than the number required by maintenance organisations. On the other hand, ten vocational schools, which have no Part-147 approval but considered as offering relevant training, are expected to graduate more than 1500 students in the next four years. This case let these students become potential employees for the maintenance organisations. However, their proper training is now much more important not only to support sustainable growth of the aviation market but also to improve the safety and reliability of the aircraft maintained.
ACCEPTED MANUSCRIPT A research study funded by Boeing’s Global Corporate Citizenship program and supported by Turkey’s Ministry of National Education has been initiated to search the means to overcome this issue. The field exercise of the study included 77 teachers from above mentioned vocational schools since improvements in their knowledge levels will result in improvements on the training of thousands of students. In order to assess the initial knowledge level of the participants, a questionnaire including complete EASA Part 66 syllabus for license category B1.1 has been sent to subject
PT
schools. The participants were asked to evaluate their readiness to deliver each Part 66 module, where;
0 means the participant has no background to teach the subject,
1 means the participants needs a refreshment to teach the subject,
2 means the participant has enough knowledge to teach the subject.
SC
RI
NU
An example where scores are arbitrary has been given in Table 4.
MA
Table 4. Self-evaluation of participants’ readiness Module
Sub Module 8.1- Physics of the atmosphere
2
8.2- Aerodynamics
1
D
8- Basic Aerodynamics
Score
PT E
8.3- Theory of flight 8.4- Flight stability and dynamics
0 0
CE
The results of the questionnaire indicated that the participants has no background around 70% of the syllabus, need a refreshment on 20% percent of the syllabus and enough knowledge to teach around 10% of the syllabus. Furthermore a test with multiple choice
AC
questions representing the whole syllabus sent to schools. The test has been prepared by subject matter expert i.a.w. Part 66 requirements where pass-mark is 75%. Minimum score was 26%, maximum score was 72% and mean score was 53. Both the questionnaire and test results demonstrated that the participants of the field exercise can be considered as an AMT candidate with no previous aircraft maintenance training and all course materials have been prepared accordingly. In the context of the project a software applicable to distance education methods has been developed. The web based software includes a virtual classroom platform where the instructors uploaded their course materials. The course materials developed by the academic
ACCEPTED MANUSCRIPT staff of the above mentioned Part-147 MTO are not limited to some texts; conversely there is an audio visual media such as schematics, animations, slights etc. Total of 253 training packages has been prepared where a package includes course notes in text format, audiovisual training material in video format and an end of chapter quiz (Fig. 3). An introduction session has been offered to participants to familiarize them with the system and interface. The participants, upon signing in to virtual classroom, are able to reach all the course materials. At the end of each sub-module a quiz was introduced to let the participant self-assess and to
PT E
D
MA
NU
SC
RI
PT
provide progression data to the instructor through a learning management system.
Figure 3. Example of a training package (original interface in Turkish language) The training model have been designed to cover certain learning outcomes as required
CE
by EASA Part-66. At the end of the complete training the attendant will; know the theory of the subject and interrelationships with other subjects,
be able to give a detailed description of the subject using theoretical fundamentals and
AC
specific examples,
understand and be able to use mathematical formulae related to the subject,
be able to read, understand and prepare sketches, simple drawings and schematics describing the subject,
be able to apply his knowledge in a practical manner using manufacturer’s instructions,
be able to interpret results from various sources and measurements and apply corrective action where appropriate.
ACCEPTED MANUSCRIPT During the project, the participants received some practical trainings and assessments in an Aircraft Maintenance Organisation. A post training test was conducted to assess if all these learning outcomes are attained and a questionnaire was send to participants to receive their responses about training. Minimum score was 70%, maximum score was 96% and mean score was 80.
Results and Discussion
PT
Aircraft maintenance is one of the primary causes or contributing factors in aircraft accidents. The growth of aviation market leading to increase the number of flights and
RI
number of passengers travelled, may result in increasing number of accidents and fatalities
SC
even though the accident rate remains constant. It is clear that proper training of AMTs will avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation
NU
and provide recovery of the increasing demand to qualified AMTs for sustainability of the market growth.
AMT training is governed by international (IATA) and regional or local (EASA and
MA
FAA) regulations. But different training models can be developed in the frame of these regulations. In this paper, AMT licencing process in EU region (and non-EU states
D
implementing EASA rules) is analysed. This process is based on the candidate’s demonstration of knowledge and acquisition of experience. The required experience depends
PT E
on the training background of the candidate. The graduates of Part-147 approved MTOs need to have minimum experience but they need extra time for training and this delays their entrance into the market. The candidates that have no approved aircraft maintenance training
CE
background needs more experience, have to self-study for the examinations but enter to the market earlier and complete their type and on the job trainings.
AC
Furthermore, the difficulties and costs to fulfil the Part-147 requirements limit the number of Part-147 MTOs and their graduates. In many countries like Turkey, AMT training heavily relies on national education system which increases the training duration. In this case, maintenance organisations start to employ staff without any approved aircraft maintenance training background. These staffs are entering to knowledge examinations while acquiring the required experience in the maintenance organisations. Now their training is much more important to make them ready for the examinations, to make some behavioural changes and to improve their awareness for the safety and reliability of the aircraft that they are working on. On the other hand, companies may not prefer to organize a training course for their employees since they will lose labour while the employees are attending to a course rather
ACCEPTED MANUSCRIPT than working and an outsourced training will have a cost to the company. This will lead the candidate to self-study and in this case he/she may face difficulties in finding appropriate training materials in own language. Funding of the training materials would be another demotivating issue. The complete EASA Part 66 syllabus for A, B1.1 and B2 category AMT licenses have been transferred to developed distance education platform. The developed software and the training model showed that AMT trainings can be delivered to public by e-learning methods.
PT
Costly times of people and companies/public institutions will not be spent by traditional face to face training. People will be able to receive their own required training whenever and
RI
wherever they want.
SC
Field exercise covered 77 teachers from vocational schools offering aircraft maintenance training and showed that developed e-learning training model succeeded to
NU
improve their theoretical knowledge level. All participants agreed that the training model gave them flexibility to decide when to and how much to study any subject. They also emphasized that diversity of the training materials was very useful. For example the material in text
MA
format was very suitable in an office environment while audio-visual material let the participants to study using their smart phones on the way to office and home. The participants
D
were satisfied with the navigating in the web based system, content delivery and interface. They implied that practical trainings in between theoretical training was very useful to
PT E
consolidate the theoretical knowledge gained but the periods could be longer. This training model can cover the students of this kind of schools, the employees of maintenance organisations preparing for knowledge examinations and shortly anybody aiming
CE
to become an AMT.
This kind of training model developed in accordance with Part-66 requirements and
AC
delivered by distance education (e-learning) methods would be very successful when combined with the practical trainings given to candidates in maintenance organisations during their experience periods.
Conclusions The literature search in the scope of this paper points the importance of training of aircraft maintenance technicians (AMTs) to reduce the number of accidents due to maintenance errors. It is emphasized that training of AMTs is vital to reduce failures, improve safety and reliability in aviation and recovery of the increasing demand to qualified AMTs in the growing aviation market.
ACCEPTED MANUSCRIPT The analysis of the licencing process based on European Aviation Safety Agency regulations concludes that this process is based on the candidate’s demonstration of knowledge and acquisition of experience. The required experience depends on the training background of the candidate. The graduates of Part-147 approved MTOs need to have minimum experience but they need extra time for training and this delays their entrance into the market. The candidates that have no approved aircraft maintenance training background needs more experience, have to self-study for the examinations but enter to the market earlier
PT
and complete their type and on the job trainings.
In countries where AMT training heavily relies on national education system, the
RI
training duration is increased and maintenance organisations start to employ staff without any
SC
approved aircraft maintenance training background.
This paper offers a training model developed in accordance with Part-66 requirements
NU
and delivered by distance education (e-learning) methods to overcome the disadvantages of face to face training. It is concluded that this model when combined with the practical trainings given to AMT candidates in maintenance organisations during their experience
MA
periods, will be very successful in improving safety and reliability in aviation maintenance
D
operations.
Acknowledgements
PT E
This study was supported by Global Corporate Citizenship program of The Boeing Company
References
CE
under grant number 16117843.
1. Birolini, A., Reliability Engineering, Theory and Practice, Springer, Berlin, 2006.
AC
2. Hobbs A, An overview of human factors in aviation maintenance. Australian Transport Safety Bureau; December, 2008. ISBN 978-1-921490-93-4 3. Safety Regulation Group, CAA, 2003, CAP 716 Aviation maintenance human factors (EASA /JAR145 Approved Organisations), http://www.caa.co.uk/docs/33/CAP716.pdf (accessed 09.10.15) 4. Marais K.B., Robichaud M.R., Analysis of trends in aviation maintenance risk: An empirical approach, Reliability Engineering and System Safety 106 (2012) 104-118. 5. EASA, Guidance on Safety Hazard Identification, 2009 http://www.easa.europa.eu/essi/ documents/ECASTSMSWG-GuidanceonHazardIdentification.pdf (accessed 09.10.15)
ACCEPTED MANUSCRIPT 6. Safety Report 2013, International Air Transport Association, Montreal, ISBN 978-92-9252349-7. 7. Federal Aviation Administration, 2014, Introduction to maintenance error analysis, http://www.faa.gov/about/initiatives/maintenance_hf/library/documents/media/hfacs/1_introduction.pdf (accessed 09.10.15) 8. IATA Safety Report, 2013 http://www.iata.org/publications/Documents/iata-safety-report2013.pdf (accessed 09.10.15)
PT
9. Rankin W., Hibit R., Allen J. and Sargent R., Development and evaluation of the Maintenance Error Decision Aid (MEDA). International Journal of Industrial Ergonomics 26
RI
(2000) 261-276.
SC
10. Safety Regulation Group, CAA, 2009, CAP 2009/05, Aircraft maintenance incident analysis, http://www.caa.co.uk/docs/33/2009_05.pdf (accessed 09.10.15)
NU
11. Liang G.F. et-al, Preventing human errors in aviation maintenance using an on-line maintenance assistance platform, International Journal of Industrial Ergonomics 40 (2010) 356-367.
MA
12. Ranking W, Maintenance error decision aid investigation process, 2007 Boeing. http://www.boeing.com/commercial/aeromagazine/articles/qtr_2_07/AERO_Q207_article3.p
D
df (accessed 09.10.15)
13. Global market forecast 2012-2031. (2012). Cedex, France: Airbus S.A.S.
PT E
14. Current market outlook 2012-2031. (2012). Seattle, USA: The Boeing Company. 15. Gramopadhye A.K., Drury C.G., Human factors in aviation maintenance: how we got to where we are, International Journal of Industrial Ergonomics 26 (2000) 125-132.
9252-349-7.
CE
16. Safety Report 2015, International Air Transport Association, Montreal, ISBN 978-92-
AC
17. Schreiber F., Human performance error management: Airbus maintenance briefing notes; 2007.http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafety Lib_-MAINT-HUM_PER- SEQ02.pdf (accessed 09.10.15) 18. Health and Safety Executive, Inspectors Toolkit: Human Factors in the management of major accident hazards, 2005, http://www.hse.gov.uk/humanfactors/topics/toolkitintro.pdf (accessed 09.10.15)
ACCEPTED MANUSCRIPT Serdar Dalkilic Anadolu University Faculty of Aeronautics and Astronautics, Department of Airframe and Powerplant Maintenance, 26470 Eskisehir, Turkey e-mail: [email protected] Oct 1st, 2016
Dear Editor,
PT
Please find below the highlights of my manuscript:
Aircraft maintenance is one of the primary causes or contributing factors in aircraft
Proper training of AMTs will avoid failures, reduce maintenance related accidents, improve safety and reliability in aviation.
Analysed AMT process is based on the candidate’s demonstration of knowledge and
NU
acquisition of experience.
MA
Proposed e-learning training model would be very successful when combined with the practical trainings given to candidates in maintenance organisations during their
Yours sincerely,
PT E
Serdar Dalkılıç, PhD.
D
experience periods.
Assistant Professor, Faculty of Aeronautics and Astronautics
CE
Department of Airframe and Powerplant Maintenance Anadolu University
AC
SC
RI
accidents.