The Role of People in Continuing Airworthiness: A Case Study Based on the Royal Thai Air Force
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32847
The Role of People in Continuing Airworthiness: A Case Study Based on the Royal Thai Air Force

Authors: B. Ratchaneepun, N.S. Bardell


It is recognized that people are the main drivers in almost all the processes that affect airworthiness assurance. This is especially true in the area of aircraft maintenance, which is an essential part of continuing airworthiness. This work investigates what impact English language proficiency, the intersection of the military and Thai cultures, and the lack of initial and continuing human factors training have on the work performance of maintenance personnel in the Royal Thai Air Force (RTAF). A quantitative research method based on a cross-sectional survey was used to gather data about these three key aspects of “people” in a military airworthiness environment. 30 questions were developed addressing the crucial topics of English language proficiency, impact of culture, and human factors training. The officers and the non-commissioned officers (NCOs) who work for the Aeronautical Engineering Divisions in the RTAF comprised the survey participants. The survey data were analysed to support various hypotheses by using a t-test method. English competency in the RTAF is very important since all of the service manuals for Thai military aircraft are written in English. Without such competency, it is difficult for maintenance staff to perform tasks and correctly interpret the relevant maintenance manual instructions; any misunderstandings could lead to potential accidents. The survey results showed that the officers appreciated the importance of this more than the NCOs, who are the people actually doing the hands-on maintenance work. Military culture focuses on the success of a given mission, and leverages the power distance between the lower and higher ranks. In Thai society, a power distance also exists between younger and older citizens. In the RTAF, such a combination tends to inhibit a just reporting culture and hence hinders safety. The survey results confirmed this, showing that the older people and higher ranks involved with RTAF aircraft maintenance believe that the workplace has a positive safety culture and climate, whereas the younger people and lower ranks think the opposite. The final area of consideration concerned human factors training and non-technical skills training. The survey revealed that those participants who had previously attended such courses appreciated its value and were aware of its benefits in daily life. However, currently there is no regulation in the RTAF to mandate recurrent training to maintain such knowledge and skills. The findings from this work suggest that the people involved in assuring the continuing airworthiness of the RTAF would benefit from: (i) more rigorous requirements and standards in the recruitment, initial training and continuation training regarding English competence; (ii) the development of a strong safety culture that exploits the uniqueness of both the military culture and the Thai culture; and (iii) providing more initial and recurrent training in human factors and non-technical skills.

Keywords: Aircraft maintenance, continuing airworthiness, military culture, people, Royal Thai Air Force.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 587


[1] C. Jackson, “The organizational value framework – the two missing legs of future organizational regulatory frameworks,” in 13th International Conference on Probabilistic Safety Assessment and Management (PSAM 13), Seoul, Korea, October 2016.
[2] C. Haddon-Cave, The Nimrod Review: An independent review into the broader issues surrounding the loss of the RAF Nimrod MR2 aircraft XV230 in Afghanistan in 2006 report. London: The Stationery Office, 2009, ch. 20.
[3] L.E. Purton and K. Kourousis, “Military airworthiness management frameworks: a critical review”, Procedia Engineering, vol. 80, pp. 545-564, 2014.
[4] International Civil Aviation Organisation, Annex 8 to the convention on International Civil Aviation, airworthiness of aircraft, Part I, Definitions, ICAO, Montréal, Nov 2016.
[5] Australian Defence Force, Defence Aviation Safety Program: Operational airworthiness in the ADF, ADF, Canberra, 2015.
[6] Royal Thai Air Force, Aeronautical Engineering Manual, RTAF, Bangkok (in Thai), 2016, unpublished.
[7] G.T. Fogarty, P.J. Murphy, W. McTernan, R. Cooper, C. Fry, K. Langford, N. Reid and H. McLean, Aviation non-technical skills guidebook, 2018.
[8] C.G. Drury, J. Ma, and C. Marin, “Language error in aviation maintenance,” Final Report. Marin, University of Buffalo, the State University of New York, Sep. 2005.
[9] J. Knezevic, “Improving quality of maintenance through simplified technical English”, Journal of Quality in Maintenance Engineering, vol. 21, no. 3, pp. 250-257, Aug. 2015.
[10] C.G. Drury, and J. Ma, “Do language barriers result in aviation maintenance errors?” in Proceedings of the human factors and ergonomics society annual meeting, vol. 47, no. 1, Oct. 2003, pp. 46-50, Sage CA: Los Angeles, CA: SAGE Publications.
[11] S.A. Shukri, R.M. Millar, G. Gratton, and M. Garner, “The potential risk of communication media in conveying critical information in the aircraft maintenance organisation: a case study,” in IOP Conference Series: Materials Science and Engineering, vol. 152, no. 1, Oct. 2016, p. 012044, IOP Publishing.
[12] H.S. Jing, and A. Batteau, The dragon in the cockpit: how western aviation concepts conflict with Chinese value systems, Routledge, 2016, pp.15-32.
[13] S.A. Shukri, R.M. Millar, G. Gratton, and H.M. Noh, “The root cause of ability and inability to assemble and install components using written manual with or without diagrams among non-native English speakers: Root cause analysis,” in IOP Conference Series: Materials Science and Engineering, IOP Publishing, vol. 270, no. 1, Dec. 2017, p. 012036.
[14] S. Schwartz, “A theory of cultural value orientations: explication and applications,” Comparative sociology, vol. 5, no. 2-3, pp. 137–182, 2006.
[15] C. Kluckhohn, Mirror for man: the relation of anthropology to modern life. Routledge, 2017, ch.1.
[16] N. Pidgeon, and M. O’Leary, “Organizational safety culture: implications for aviation practice,” Aviation psychology in practice, pp. 21-43, Mar. 1994.
[17] M. Rachman, Achieving zero accidents: a study of the influences of Indonesian national and military organisational cultures on aviation safety. A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy, School of Management, College of Business, RMIT University, Australia, 2018.
[18] B. Falconer, “Human factors and the QFI: developing tools through experience,” Multimodal Safety Management and Human Factors: Crossing the Borders of Medical, Aviation, Road and Rail Industries, 2007.
[19] M.R. Devries, K.H. Hughes, H. Watson, and B.A. Moore, “Understanding the military culture”, Handbook of counselling military couples, pp. 221-231, Apr. 2012.
[20] J.L. Soeters, and P.C. Boer, “Culture and flight safety in military aviation,” The International Journal of Aviation Psychology, vol. 10, no. 2, pp.111-133, Apr. 2000.
[21] M.Y. Liao, “Safety culture in commercial aviation: differences in perspective between Chinese and Western pilots,” Safety Science, vol. 79, pp. 193-205, Nov. 2015.
[22] R.L. Helmreich, and A.C. Merritt, Culture at work in aviation and medicine: national, organizational and professional influences. Aldershot: Avebury Technical, 2001, pp. 27-107.
[23] P. Hallinger and P. Kantamara, “Educational change in Thailand: Opening a window onto leadership as a cultural process,” School Leadership & Management, vol. 20, no. 2, pp. 189-205, May 2000.
[24] Australian Transportation Safety Bureau, An overview of human factors in aviation maintenance, AR-2008-055, ATSB, Canberra, 2008.
[25] A.K. Gramopadhye, and C.G. Drury, “Human factors in aviation maintenance: how we got to where we are”, International Journal of Industrial Ergonomics, vol. 26, no. 2, pp.125-131, 2000.
[26] Defence Aviation Safety Authority, Requirements for maintenance organisations, DASR 145, DASA, viewed 5 August 2019,
[27] Defence Aviation Safety Authority, Factoring the human element into maintenance, DASA, Canberra, 2014.
[28] Y.H. Chang, and Y.C. Wang, “Significant human risk factors in aircraft maintenance technicians,” Safety Science, vol. 48, no. 1, pp. 54-62, 2010.
[29] A. Hobbs, “An overview of human factors in aviation maintenance”, ATSB Safety Report, Aviation Research and Analysis Report AR, vol. 55, Dec. 2008.
[30] J.C. Taylor, “The evolution and effectiveness of Maintenance Resource Management (MRM),” International Journal of Industrial Ergonomics, vol. 26, no. 2, pp. 201-215, Aug. 2000.
[31] A. Irwin, S. Taylor, E. Laugerud, & D. Roberts, “Investigating non-technical skills in Scottish and English aircraft maintenance teams using a mixed methodology of interviews and a questionnaire,” The International Journal of Aviation Psychology, vol. 26, no. 3-4, pp. 105-119, Oct. 2016.
[32] N. Engel, R.E. Patey, S. Ross, and L. Wisely 2008, “Non-technical skills,” British Medical Journal, vol. 337, Dec. 2008. (BMJ 2008; 337 doi:
[33] G. Albaum, “The Likert scale revisited,” Market Research Society, Journal, vol. 39, no. 2, pp. 1-21, Mar. 1997.
[34] L. Herkenhoff, and J. Fogli, Applied statistics for business and management using Microsoft Excel, New York: Springer, 2013, pp. 283-302.
[35] J. Sauro, “Can you take the mean of ordinal data?” viewed 23 September 2019,
[36] M.B. Davies, Doing a successful research project: using qualitative or quantitative methods, Palgrave Macmillan, New York, USA, pp. 53-151, 2007.
[37] J.C. De Winter, and D. Dodou, “Five-point Likert items: t test versus Mann-Whitney-Wilcoxon,” Practical Assessment, Research & Evaluation, vol. 15, no. 11, pp. 1-12, Oct. 2010.
[38] J.H. Flaskerud, “Cultural bias and Likert-type scales revisited,” Issues in Mental Health Nursing, vol. 33, no. 2, pp. 130-132, Jan. 2012.
[39] L. Retief, M. Potgieter, and M. Lutz 2013, “The usefulness of the Rasch model for the refinement of Likert scale questionnaires,” African Journal of Research in Mathematics, Science and Technology Education, vol. 17, no. 1-2, pp. 126-138, Sep. 2013.
[40] K. Rajprasit, P. Pratoomrat, and T. Wang, “Perceptions and problems of English language and communication abilities: a final check on Thai engineering undergraduates,” English Language Teaching, vol. 8, no. 3, pp. 111-120, 2015.
[41] P. Shawcross, English for aircraft maintenance, Paris: Berlin, 1992.
[42] Defence Aviation Safety Authority, Introduction to defence aviation safety, 2nd edn, DASA, Canberra, 2019.
[43] P.H. Wilson, “Defining military culture,” The Journal of Military History, vol. 72, no. 1, pp. 11-41, Jan. 2008.
[44] Defence Aviation Safety Authority, Defence aviation safety management guidebook, 21st edn, DASA, Canberra, 2016.
[45] A.V. Chatzi, 2018, “Safety management systems: an opportunity and a challenge for military aviation organisations,” Aircraft Engineering and Aerospace Technology, vol. 91, no. 1, pp. 190-196, Jan. 2018.
[46] V.M. Iordache, and C.V. Balan, “Safety culture in modern aviation systems-civil and military,” Incas Bulletin, vol. 8, no. 2, p. 135, Apr. 2016.
[47] R. Reynolds, E. Blickensderfer, A. Martin, K. Rossignon and V. Maleski, “Human factors training in aviation maintenance: impact on incident rates,” in Proceedings of the Human Factors and Ergonomics Society Annual Meeting, Sage CA: Los Angeles, CA: SAGE Publications, vol. 54, no. 19, pp. 1518-1520, Sep. 2010.
[48] Defence Aviation Safety Authority, Military aircraft maintenance licencing, DASR 66, DASA, viewed 8 September 2019,
[49] C.V. Thian, “Civil and military airworthiness challenges in Asia,” Aviation, vol. 19, no. 2, pp. 78-82, Apr. 2015.
[50] Defence Aviation Safety Authority, Military aircraft maintenance licencing, AC 001/16 Revision 01, DASA, Canberra, 2017.
[51] H. Le, and I. Lappas, “Continuing airworthiness: major drivers and challenges in civil and military aviation,” Aviation, vol. 19, no. 4, pp. 165-170, Oct. 2015.
[52] S. Geller, “10 leadership qualities for a total safety culture: Safety management is not enough,” Professional Safety, vol. 45, issue 5, pp. 38-41, May 2000.
[53] F. De Florio, Airworthiness: an introduction to aircraft certification and operations, 3rd edn, Amsterdam, Netherlands: Butterworth-Heinemann, 2016, ch.10.
[54] M. Lundell and C. Marcham, “Leadership's effect on safety culture,” Professional Safety, vol. 63, no. 11, pp. 36-43, Nov. 2018.