For many years aircraft grade aluminium has been the main material of construction for aircraft bodies and wings, mainly due to its excellent fatigue resistance and balance of properties. In addition, given the harsh environment encountered both on the ground and in the air (temperature variation, rain, ice, snow, sunlight, aviation fuel, cleaning materials, bird strikes, fatigue and impact loading etc.) the material is required to resist all these conditions, and also has to be corrosion resistant. Light weight is a prime criterion for a material to be used in aircraft, which is satisfied by aluminium.

A new material - carbon fibre reinforced plastic (CFRP) seems poised to supersede the universal use of aluminium. This material will be used in the wings of the new Airbus A350, A380 and on structural components of the new military liftplane, the A400M. The A350XWB (Xtra Wide Body) will use carbon fibre reinforced plastic (CFRP) panelled fuselage skins that are easier to repair and maintain. Weight saving is achieved via optimum fibre lay-up and skin thickness is tailored to the requirements of the specific location. This all new composite wing design will yield wings spanning 64 meters on a 66.9 meters long body. The maximum take off weight of the A350 is 265 tons.
Airbus introduced composites way back in the late 1970s on secondary structures in the A310 aircraft. By 1985, composites were applied on primary structures and in the innovative drag-reducing wingtip devices on the A310-300. Today, composites are used throughout aircrafts such as the A380. A380 is also the sole commercial plane employing them in the centre wing box and rear fuselage.
The world's first carbon-fibre keel beam for a large aircraft was built for the A340-600, and Airbus' 21st century airliner - the 525-seat A380 - is continuing the tradition of innovation with the increased use of carbon fibre reinforced plastic (CFRP). Airbus has the first application of glass fibre-aluminium laminate on a civil airliner, and was also the first to introduce laser beam welding on a civil aircraft on the A318.
The entire fuselage skin of Boeing's new 787 twin-engined widebody jet, due to enter service this year, will consist of composites. The skin and spars of the 787's wings are made of composite material too, though the ribs that shape and stiffen the wing from front to back are aluminum. Composite materials make up roughly 50% of the 787.

In addition to composites, several other high performance plastics are used within modern aircraft. Boeing, for example is using PEEK supplied by Victrex for the hubcaps of a tyre pressure monitoring system.  The parts have to withstand 200° C braking temperatures, along with in-flight air temperatures as low as -50° C.  In addition, jet fuel and de-icing solutions may come into contact with the tyre pressure system, necessitating the use of such a sophisticated plastic. PES supplied by Sumitomo is used in carbon fibre composites as well as electronic components and membranes.  The plastic has an impressive specification including light weight and high heat resistance, coupled with strength and transparency.

Employing composites will make airliners more reliable, keep maintenance costs down, make airliners lighter, reducing fuel costs and allowing them to carry more passengers and cargo--or fly longer distances--at their maximum takeoff weights. Tomorrow's largely composite airliners also will improve the flying experience for passengers. Making airliner fuselages out of composites banishes the fear of metal fatigue and corrosion that has constrained designers until now. Passenger-cabin air can be moister and kept at higher pressure, so passengers feel less dehydrated and don't find themselves gasping for breath.