Nick Baird is sales director of Permali Gloucester Ltd. of Gloucester, UK. He studied aeronautical engineering and initially worked as a design engineer on aircraft hydraulic and pneumatic systems. He joined Permali Gloucester as a sales manager responsible for aerospace products and later became sales director with overall responsibility for all markets which include rail, motorsport, defense and aerospace.
How has the use of composite materials grown in the defense industry?
I would start by saying that the use of composites in defense is nothing new! The use of wood-fiber based composites on aircraft dates back to World War II, and glass fiber composites have been used in armor and naval applications for over 40 years. However, the use of composites continues to grow in defense, certainly for armor applications and increasingly for primary structures in aircraft, vehicles and ships.
Why is there a trend toward more use of composites in defense applications?
There has been a massive increase in the use of composites for armor over the last 10 years. This has been driven by the much greater “mass efficiency” of composite armors compared to metallic systems in stopping any given threat, and generally the advantages of composites are even greater when faced with the most severe threats such as IEDs (improvised explosive devices).
Composites also have other significant benefits, such as much reduced “behind armor effects” ― this is the tendency of metal vehicle hulls or armor to spall or splinter when they are penetrated by a severe threat. You can never design an armor system to stop everything, but you can design a system to reduce the number of injuries or fatalities when you do get hit by something big.
What challenges do composites present in defense applications?
As composites are introduced into various new applications, the main issue is a lack of familiarity by both the buyers and the users. Composites require different inspection and repair techniques to metals, so it is crucial that high quality training and documentation is provided to the operators in the field and at repair stations.
What other benefits do composites offer compared to steel or aluminum?
Composites have inherently lower radar signatures than metals, although this is just one aspect among many when designing for stealth. This is a key benefit to the use of composites for topside structures on ships and is becoming an issue for armored vehicles.