FLIGHT REPORT: BKK – CNX THAI 787
The use of composite materials in the aerospace industry has improved drastically over the past century. Dating back to the fiberglass insulation used in B-29 fuselages during WW2, composite materials were beneficial over traditional aircraft construction materials such as aluminum, steel and titanium. The benefits of composite materials are reduced weight, high strength to weight ratio, design flexibility, corrosion resistance and assembly simplification making composite materials popular in military aviation. Weight sensitive aircraft such as the V-22 osprey and the F-18A used composites such as fiber reinforced epoxy and graphite. Composite materials are also popular in civil aviation as seen by the incorporation of composites into 50% of the structures of the Boeing 787 and Airbus A350 XWB, next generation airplanes.
A composite material is when two or more materials are combined to create a stronger material with more versatile characteristics. Composite is a general term and can be referred to different materials such as fiberglass, Kevlar, carbon fiber cloth, epoxy or a mixture of them all.
Composite materials are fiber reinforced matrix systems. The matrix glues the fiber into place giving the shape; the fibers carry most of the load. In aviation, many types of matrix systems are implemented. The most common matrix is the epoxy resin. Epoxy is a thermosetting plastic, which has good high temperature properties and high strength. Epoxy, paired with reinforcing fibers such as carbon fiber and fiberglass creates a superior composite with high tensile strength, lightweight, and good impact strength. This expands the applications of this composite from the construction of doors and cabin interior to load bearing parts such as the tail feathers.
Despite all the perks of composite materials, it comes with disadvantages. The first is the lack of visual proof of damage. A composite can be significantly weakened but shows to visible physical change. There is a lack of visual proof of damage. Composites respond differently to damage than other materials. A rough landing or a low energy impact such as a little collision may not leave a visual sign. However, underneath there may be delamination and damage spreading away from the impact location. This is dangerous in the world of aviation.
