If you put down a list of material properties for a plane, you would of course have lightness as the main criterion - it stands to reason that if you have to spend money on fuel to propel an aircraft into the sky, you need the aircraft to be as light as possible. 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.) you would need a material that was resistant to all the aforementioned and was resistant to corrosion. Lastly you would need a material that was not affected by lightning strikes. Surprising therefore that until very recently, the chosen material group for this application was metal. Aluminium has for many years been the main material of construction for aircraft bodies and wings. Not any old aluminium of course - so called ‘aircraft grade' has been selected for many years due to its excellent fatigue resistance and balance of properties.