Putting pedal to the metal

As far as relationships go, aluminium and its use in the aerospace industry are a bond that has aged well. The ties date back to the 19th century; the first use of aluminium in aerospace was in the making of frames by Count Ferdinand Zeppelin in his ‘airships’.

This historic relationship finds a place in the Wright Brothers’ story. The cylinder block and other parts of the Wright Flyer in 1903 were made of aluminium; they were light yet strong enough for a successful take-off. Aluminium against a wooden frame that was in use then ensured that the aircraft lifted off with the intended weight.

Aluminium use in aerospace grew when alloys emerged as an option as racing aircraft became a rage in Europe and America in the 1920s.

The alloys did not rot and splinter like wood and led to a significant weight loss in an aircraft, allowing planes to carry more weight or improve fuel efficiency.

The Boeing 737 aircraft consists of 80 per cent aluminium alloys. It is lighter but stronger and corrosion resistant. Aluminium is used in aircraft fuselage, wingspans, doors, flooring and even passenger seats.

Having made it to spaceships there is no doubt that the confidence in aluminium will continue into the next generation of aircraft since performance characteristics and costs have been set along with modern production facilities.

Aluminium’s use in aerospace is with a combination of various alloys. When strength to weight ratio is needed and the alloy has to be tough, it is combined with copper or zinc; and generally used in wingspans and fuselage given the tension that these parts have to withstand.

Both aluminium and composite materials have their strengths but aluminium is more established in its advantages. It is cheaper than composite material which is also prone to degradation from ultraviolet rays.

Innovation holds the key to the future. If zinc is the present for aluminium alloys, the future is in using aluminium-lithium alloy. Research indicates aluminium-lithium alloys or Al-Li alloys offer a 10 per cent weight reduction in comparison to composites.

With the industry continuing to gain from using aluminium alloys in providing for a safer, reliable flight and keeping aircraft manufacturing low, the future and use of this versatile metal are poised for a long flight into the future.