Covington Aircraft posted a blog post last week comparing Aluminum (Aluminium, for our Imperial friends) versus Composite, and which was the better material for airframes.It was an interesting article, cleverly speaking to the pros and cons of each material rather than trying to take a particular side. Even so, it kicked off a discussion internally about what we thought.We came to the consensus that we don't think there is a comparison left at this point.Why, you're probably asking?It's simple really: if you think of where we are in aviation today, if we haven't already reached our limits in conventional aircraft design then we're certainly approaching them.In the quest for stronger, lighter, and more economical aircraft, both Boeing and Airbus are leading the charge in the large-scale use of composites with the B787 and the A350. These aren't lightly utilized aircraft, either - they operate on the flight schedule just like any other, and maintenance has to service them on the line when things go sideways.So is there really a comparison between the two materials?We would offer that no, that day has come and gone. Will aluminum continue to be used? Sure, we'll likely always use it to some extent. Will aluminum be the material of choice as we move towards the "next frontier" in design efficiency? Probably not.Today, we're creating "greener" aircraft, lowering aircraft weight, and using new material combinations... but we still seem to be limited by the basic design and materials that we're using. Changing the inherent design of aircraft is the next step, and it turns out the industry is already headed in that direction.Smart people are working on that "next frontier" already, and composite materials are at the heart of it. Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) may be the next significant change to our inherently circular design of an aircraft fuselage. The link provides some detailed information on the thought process, but essentially the idea is to use composites to create non-circular aircraft fuselages using the construction concept you see below.Composite stringers for commercial, non-circular pressurized cabins... who would have thought it, right?There's no doubt in our minds that we'll see significantly more fuel-efficient aircraft flying around in the years to come, thanks to composites - maybe in something similar to Boeing's Blended Wing Body (BWB) concept below. As recently as 2013, Boeing Phantom Works and the NASA Langley Research Center were highly optimistic about the program and were building a transonic demonstrator.Either way, it appears composite "wins" over aluminum in the long term, as it seems to be key to future designs that reduce aircraft operating costs. Maintenance on composites aircraft is obviously a far different beast than working with aluminum ones, of course, but as the market continues to develop so will new tools and processes to make our lives easier.So that's our take on it - anyone else? We'd love to hear from you.