Despite the need to save weight the unique range of properties available from steels mean that it will, for the foreseeable future, still have a place in commercial airliners. In the Airbus A380, which was introduced in 2005, steel was about 5% of the total weight. In the more recent Boeing 787 Dreamliner this had grown to 10%, although this may be because of the increased use of composites rather than a doubling of the weight of steel used.
Future developments which could influence the use of steels in aerospace applications focus predominantly on the propulsion systems.
The next generation of engines is likely to be geared such that the speed of the turbine and the fan can be controlled separately to maximise engine efficiency. This will initially involve the use of existing gear steels, but in the longer term may require the development of improved alloys which can operate at higher stresses and temperatures.
Work is also being carried out to develop electric propulsion systems, either in hybrid or fully electric configurations. These are currently being directed towards short haul flights as there is a weight penalty associated with the batteries. Unlike conventional fuel which is burnt off during flight, the weight of the batteries remains the same which is a particular disadvantage on longer flights. However this new technology will bring new opportunities for electrical steels.