Change Agent

Michael J. Hoke, Owner and President Abaris Training Resources, Inc.

Mike Hoke has worked in production and repair of composite aircraft since the 1960's, and became president of Reno, Nevada-based Abaris Training Resources, Inc. in 1990 after a close partnership with William L. Murphy, who founded the company in 1983. Since inception, Abaris has trained some 11,000 technicians, depot managers, and engineers from commercial and military OEMs and operators. Abaris is thriving with a 10-member global staff; recent expansion of the Reno facility; ongoing success wth its Georgia facility; the establishment of Heatcon Abaris Training International Ltd. in Wales offering European students advanced composites training; a new "Basics of Composite Repair" online course; and course offerings planned for 2007 in NDI techniques and equipment.

AM: Your company motto is "composites are our livelihood." Does that mean there's no Abaris training for metal benders doing MRO tasks?
Hoke: While the bulk of our expertise is in composites, just because you can build something with these materials doesn't always mean you should. Metals still fit better in certain cases. We offer a five-day course in repair of bonded aluminum structures and a five-day course in advanced bonding of composites and metals, since composite patches have been used to repair aluminum structure for some time. Also, as more composites come onboard new aircraft, more techicians and engineers with metals experience will want to expand their knowledge to include composites.

AM: Does that mean an end to the reticence sometimes encountered from upper management regarding composites, even as shop floor techs who are hands-on with these "new" materials (albeit with a hundred year history or more) can already see the benefits?
Hoke: There is still some resistance to all-composite aircraft from a damage-tolerance standpoint, in part because non-visible damage is more complex to detect in composites than in metals. The FAA held a conference in July to address these exact issues. Larger, long-haul aircraft such as the Boeing 787 that are not as close to the ground as the 737, for example, will likely fare better with composites in the fuselage, pressure vessel and inlet cowls, which see the most common type of ground impact damage. Still, one of the key advantages of composites is that damage usually doesn't tend to spread, as it does with metals.

AM: Can composites be considered "fly away and forget" materials relative to fatigue or corrosion damage?
Hoke: Not entirely. Loose fasteners rocking in a composite fastener hole will cause fatigue mode degradation over time. In a way, helicopters are "flying fatigue testers" due to millions of operating cycles flown with composite blades, hubs and fasteners. Carbon fiber composites can cause galvanic corrosion when in contact with metals, though there are ways to design around that problem. And paint stripper, when used by untrained personnel, can attack the resin matrix in a composite part and create unexpected damage, though paint stripper usually doesn't affect metals.

AM: That emphasizes the importance of training in design, production, and repair of composite structure and components. Is the aircraft industry more willing now to invest in such training?
Hoke: We're seeing more course attendance overall, and particularly by general aviation personnel, as well as students seeking information on rapid tooling methods for composite repair (see AM, September 2006, p. 40). The FAA is considering creating composite repair training certification in some formal manner. That may take several years, and we hope to be part of the development effort. Training is even more critical now that Boeing and Airbus are using thicker composite structures with higher ply counts in new aircraft, so damage assessment will require more skill. A tap test won't be effective 75 plies down, and scarf angle repair in these thicker laminates will take more time and care. Mechanical repair such as bolted doublers may work better than repair techniques used for thinner laminates. I know the OEMs are working strenuously on these issues, and Abaris will continue to adjust course content to reflect new composite repair requirements.

AM: Do you think we've truly reached the era of the "plastic" airplane?
Hoke: Plastic may not be the best term, as people might think of a child's plastic swimming pool or plastic house siding. Aircraft composites, which are high performance, fiber reinforced resin-matrix materials, are definitely coming into their own. That's a done deal, not a question anymore.