NASA announced January 4 that a team of composite experts have designed, produced, and are now testing an all-composite space capsule for deployment in future spacecraft designs – a first for the U.S. space agency. The composite capsule will undergo systems tests until March 2010 at NASA’s facilities in Langley, VA.

The adoption of composites represents a revolution in aircraft manufacturing – a change as significant as the switch from wood to aluminum in the 1920s. However, aviation is still grappling with how this historic trend will change conventional ways of flying, whether in the atmosphere or in space.

The increasing prevalence of composites reached a milestone on December 16, when Boeing completed the long-belated first test flight of its new 787 Dreamliner, ushering in a new era of composite-based aircraft that will save airlines millions of dollars in fuel costs.

Airlines have responded enthusiastically to the twin-aisle, mid-sized plane that can carry about 250 people on extended trips. Carriers have placed orders for 840 Dreamliners, worth roughly $140 billion, since Boeing started working on the plane in 2004. However, production on this “game changing” aircraft has been delayed five times in the past three years, due to a shortage of spare parts, faulty design, production snafus, and a protracted machinists’ strike at Boeing’s Seattle factory. Even more embarrassing for Boeing, first flight has been postponed six times.

Meanwhile Boeing’s arch rival Airbus, a subsidiary of European-based EADS, has been garnering buyers for its competing A350 plane, also manufactured primarily from carbon-composite materials.

NASA has never certified composites for a spacecraft intended for human flight. Composites are miracle materials but they also present many unintended consequences that aerospace firms still haven’t sorted out.

This topic was discussed during a recent Aviation Today-moderated podcast interview: Why The Increasing Use of Composites Makes Training More Vital.

In this podcast, Aviation Today interviewed Michael Hoke, president, Abaris Training Inc., based in Reno, NV. The podcast was recorded and archived; you can access and listen to it for free by clicking here:
www.aviationtoday.com/podcasts

Abaris conducts “hands-on” training classes in advanced composite aircraft structural materials, such as carbon fiber, Kevlar, and fiberglass. The company offers 17 different classes in manufacturing and repairing composite components. Most of Abaris’ classes are geared for the A&Ps and other technicians who physically undertake the work with their own hands, or for their supervisors.

Below is an excerpt of Aviation Today’s 15-minute interview with Mike Hoke:

Q: Explain to us how the use of composites is increasingly pervasive in the aviation and aerospace sectors. The Boeing 787 is a “game changing” aircraft that’s all composite and it exemplifies this watershed in the industry. Quantify for us how the use of this high-tech material is spreading, and what it means for aviation players of all types.

Hoke: There is no question that the use of modern high-performance composites is rapidly spreading throughout the industry. The primary reason is not weight savings, which many people think. While saving weight is indeed possible in well-designed composite structures, other advantages often are the deciding factor. The ability to create complex one-piece shapes with multiple compound curves while maintaining a very smooth aerodynamic surface, with no rivet heads or seams, is a significant benefit. Lack of corrosion is another, leading to real reductions in maintenance costs, especially in transport category aircraft as they age. Good performance in vibration and fatigue environments is another big advantage, and has lead to the fact that almost all new helicopters are using all-composite blades, and in many cases composite rotor hubs as well. The aerodynamic benefits are especially popular in smaller general aviation and UAV aircraft. In addition, the radar signature reduction benefits, compared to aluminum, are very significant in military manned and unmanned aircraft.

Q: Composites aren’t necessarily a silver bullet, are they? What are the pros and cons of using them?
   
Hoke: You’re absolutely right. Like anything else in engineering, composites have both advantages and disadvantages, and there are areas in which metals are a better choice. I have already discussed some of the advantages, so I will address some of the disadvantages. From an engineering strength point of view, composite laminates tend to not do very well in compression loading, compared to metals. While they certainly can bear compression loads, the potential for weight savings largely disappears when compared to metallic structures.

Q: Considering all of these trends that you just fleshed out for us, what are the implications for training?

Hoke: Composites are not inherently difficult to build or to repair. However, the techniques used and the skills needed are often quite different than those for metallic structures. Many more adhesively bonded repairs, rather than mechanically fastened repairs, are used on thinner composite laminates, for example. The “riveted doubler” technique used on so many aluminum structures is usually not applicable on composites, except on thick solid laminates, and will in fact seriously compromise a thinner composite structure and create a potentially dangerous situation.

Q: When it comes to composites, what qualities set effective training apart from ineffective training?

Hoke: One of the areas that help to make our training effective is our ability to keep the students interested and enthusiastic about the training. This whole area of advanced composite materials training is quite technical, and has the potential to be deadly dull and boring in the wrong hands. We all know people who might be technical experts in a given area, but would put a classroom of students asleep in about five minutes. So while of course I hire technical experts as instructors, I also am very cognizant of their personalities as teachers. They absolutely can’t be boring and dull, and their personalities are a very large part of our success. Most of our customers come from either the military aircraft or transport category aircraft environment. Aircraft manufacturers, MRO facilities, repair stations of all sizes, helicopter manufacturers and operators, military repair facilities, and so on are where we get the majority of our business. We also do a significant amount of training in the spacecraft industry, with satellite and launch vehicle manufacturers, as well as a lot of business from various NASA facilities. UAV manufacturers and operators are another significant addition to our business in recent years.

John Persinos is publisher and editorial director of Aviation Today (jpersinos@accessintel.com; 301-385-7211). You can access for free his entire podcast interview with Michael Hoke by clicking here:

www.aviationtoday.com/podcasts/