From the first fibreglass materials used in Boeing 707 in 1950s to the modern Boeing 787 Dreamliner, the utilization of composite materials in aviation has been rapidly developing, particularly over the past decade. However, despite significantly reducing aircraft weight, composite materials are less ‘predictable’ than the aluminium-based components and are harder to be examined for various cracks and flaws. As a result, composites remain a topical issue within the MRO community, particularly in the segment of maintenance training.
At the dawn of the composite era they accounted for a mere several percent of all components in commercial aircraft. However, over the past 20 years jet fuel prices have risen from approx. $23/bbl. to $125/bbl thus triggering a natural demand for aircraft with more effective fuel systems. This, amongst other factors, has encouraged manufacturers to develop and introduce new materials which would ensure uncompromised performance with reduced fuel consumption.
‘Weight is essential when it comes to aircraft fuel consumption. The utilization of composites in such aircraft as Boeing 787 Dreamliner, where they correspond to about 50% of the structural weight, helps to reduce the final weight of the aircraft by approx. 20% in comparison to the usage of aluminium materials. 53% of the upcoming Airbus A350 will be also made of composite materials,’ comments Kestutis Volungevicius, the Head of FL Technics Training.
However, in spite of the accelerating trend of their utilization, composites still remain relatively new materials, particularly in the aircraft repair segment, as aircraft with a significant amount of composite content have only recently started penetrating the market.
According to Mr. Volungevicius, composites are characteristic of a much more complicated structural design than aluminium components. Furthermore, they are less ‘predictable’ than traditional materials and more prone to such issues as complex damage (fibre cracks, flaws, etc.). Handling and inspecting composite materials requires not only more sophisticated Non-Destructive Testing (NDT) methods, but also higher qualification of the staff specializing in complex composite repairs.
‘Practical experience is essential when it comes to composite repair training. Unfortunately, not every MRO provider has an extensive experience in composite repair segment, left alone a training organization. Then there is the lack of an industry-wide standard with regard to the training programs to consider. For these reasons, whether it is an MRO company or an individual wishing to develop a career in aircraft maintenance, one has to choose a composite repair training organization especially carefully. It is vital to evaluate the opportunities for both practical internship after theoretical courses and the compliance of such an organization with standards of the major aircraft manufacturers,’ concluded Kestutis Volungevicius.