When it comes to determining how well an aircraft will perform, the thrust-to-weight ratio is one of the most important metrics. Aerospace manufacturers have always aimed to keep this ratio as low as possible by creating lighter aircrafts, but the metals traditionally used in aircraft bodies are heavy. Composite materials, on the other hand, are lighter and enable manufacturers to create more fuel-efficient aircrafts when mixed with metal. Let’s examine the history of composites in the aerospace industry and where future innovation is headed.
How composites changed the aerospace industry
In the past, composites were mainly used in military aerospace applications. Manufacturing civilian aircrafts with composites was considered too expensive, and if composites were part of their design, they were typically used for non-structural applications. This changed when the civilian aircraft industry had to respond to the rising cost of oil and pressures due to environmental concerns. The more lightweight aircraft structures that result from substituting composite for metal have lower fuel costs and reduced emissions. While only 12% of the Boeing 777’s weight was composite, the Boeing 787 used 50% composite by weight. Composites are now commonly used in civil aircraft structures in increasing amounts.
Benefits of composites for aerospace
The lightweight nature of composites is far from their only benefit for the aerospace industry. Composites also have high impact resistance, thermal stability, and damage tolerance: properties that enable aircrafts constructed with composites to fare better in accidents. Additionally, composites are better at resisting fatigue and corrosion than traditional metal. They are also easy to assemble. As composite technology continues to improve, all of these benefits are becoming more pronounced, and the costs of building aircrafts with composites are going down.
Balancing lower weight with noise control and passenger comfort
The development of lighter aircrafts through composites helps aircrafts become safer and more fuel-efficient, but manufacturers also need to consider the comfort of the passengers in the cabin, excessive noise is often one of the main sources of cabin discomfort. Reducing the weight of the fuselage through lighter materials can result in a noisier ride if lower weight is prioritized over the need for noise and vibration reduction. Composite parts can, however, be formulated and constructed to provide effective vibration damping. Incorporating lightweight insulation and cushioning materials allows composites to provide better vibration damping and airborne noise absorption, resulting in an airplane ride that is much more enjoyable for the passengers and pilot.
The future of composite aircrafts
We’ve come a long way since composites were first introduced to the military aerospace industry. As we look toward the future, the industry will keep demanding lighter, more efficient aircrafts. Eventually, we may see aircrafts constructed entirely of composite rather than metal, but for now, aircrafts are still only part metal, part composite.
In the meantime, we should expect materials manufactures to upgrade current composite systems so they provide more effective vibrational damping along with their lightweight properties. Aerospace manufacturers will therefore need to continue working alongside materials manufacturers to further develop the innovations that will facilitate the production of more efficient, quieter, and safer aircrafts for civil and military use alike.