Q: Clearly, composites fit in the overall strategic vision of the Air Force. Can you talk about any specific applications you are working on?
A: We’re looking at a new class of airplanes – something called Low Cost Attritable Aircraft Technology (LCAAT), which is an unmanned aircraft that is cheaper than traditional manned aircraft, but meets capability requirements. Leadership has given us the [cost] goal of $3 million a plane, not counting the payload. That’s a lot different than what you see today with our strategic assets like an F-35 fighter, B-2 bomber or Global Hawk unmanned aircraft system. These cost millions, if not billions of dollars.
If we need something really cheap, but still require long-range capabilities to get where we need to go, composites are going to be the solution. But it may not be the kind of composites we use today. It may be something adopted from outside the aerospace industry that helps us achieve high volumes affordably so we can make a lot of these things.
Q: So if LCAAT isn’t going to utilize traditional aerospace material, can you elaborate on what those materials might be?
A: We’re looking at what’s going on in the automotive and marine sectors, more in terms of the processes than the material. We still need the performance to go 3,000 nautical miles, and our aircraft are still going to be sitting out on a runway in the sun, so we will need higher temperature capabilities compared to what a car in your driveway would see. The aircraft will fly at around Mach .9, so again temperature and range will drive us to aerospace materials. But we may need to look at some alternative manufacturing processes that offer us higher volumes and higher speeds.
Q: What projects is AFRL currently working on to advance composites in aerospace applications?
A: Within basic research, we are starting to look at how to merge additive manufacturing with composites. We’re looking at thermoset resins rather than thermoplastics, which is what you currently see today. Can we incorporate carbon fibers in a continuous manner? For several years we’ve also been researching multifunctional structures – looking at adding antennas in composites or embedding some kind of health monitoring system in composites. We’re still a long way off, but the more you can integrate into the structure, the better aerodynamic lines for your airplane.
We’re also working with DARPA [the Defense Advanced Research Projects Agency]. Composites are really good right now for big parts, but for small parts we default to aluminum because it’s a lot cheaper. What if we can make composite part sizes of 20 pounds or less as cheap or cheaper than aluminum? There are lots of those parts on airplanes. That could save a ton of weight if we could get the cost right.