As stricter environmental protection regulations evolve, aviation MROs are exploring and implementing more creative solutions to materials recycling and repurposing. Vendors are finding new ways to reuse materials that would have gone to landfills just a few years ago. Briefly put, the waste-reduction landscape is undergoing change, which is being driven largely by the MROs themselves.
For example, as more airlines consider cabin refreshing, Earl Diamond, CEO of Avianor, believes he has found a unique approach in which both the customer and the environment come out ahead. Based at Montreal-Mirabel Airport, Avianor is a specialist in full-service cabin integration.
As Diamond explains, the company purchases interior components from sources that are retiring or parting-out aircraft, doing fleet-wide cabin upgrades or passenger-to-cargo conversions. “We were actually offered a complete passenger interior by a company doing a freighter conversion, just for the cost of shipping it to our facility,” says Diamond. “They wanted it off their hangar floor, and had we not taken it, it might have ended up in a landfill.”
The components typically purchased include sidewall panels, overhead bins, galleys, lavatories, seats and inflight entertainment systems. In some cases, those components may be consigned by an operator to Avianor for resale, or stored for possible later use by that operator.
But for the most part the fittings will find their way into a new interior for an airline customer—either in full or in combination with newly manufactured pieces, which Avianor fabricates in house. “We think we may be the only MRO offering complete cabin make-overs using fully reengineered and repurposed interior components to the airlines,” says Diamond. Those components can be installed at Avianor’s hangar, or provided as a kit for installation at the customer’s facility of choice.
The customer, says Diamond, benefits from a savings in cost and time. A repurposed interior can represent at least a 50% savings over the cost of using brand-new parts from Boeing and Airbus, along with avoiding a typical 90-120-day lead time for delivery from the OEM, he says. “The OEMs don’t always have what the airline needs—and in the quantity they need—ready to ship to when the airline needs it.”
Diamond says that about 20% of the material procured for a specific job usually will be used for that project. “That 20% covers our acquisition costs, and the other 80% will be held in inventory.” In that regard, he adds that the economics of interior reuse tend to favor large fleets, which is why Avianor’s market concentration is on the Airbus A320 and A330, and the Boeing 737NG, 767 and 777 families. “When multiple aircraft are involved, engineering costs are spread out, and parts can be stored and used on future jobs.”
Using restorable components to avoid disposal has been integral to carbon brake heat-sink overhauls at Meggitt Aircraft Braking Systems in Akron, Ohio. According to Frank Crampton, the company’s executive vice president, Meggitt has pursued innovations in the reuse of worn rotors and stators since the widespread use of carbon for those parts began in the 1970s.
Specifically, Meggitt developed what it calls “Two-For-One Carbon Heat- Sink Recycling” for refurbishment of the first generation of carbon brakes manufactured from the 1970s through the early 1990s. Aircraft certified with these components—such as the Boeing 757, the Fokker 70 and 100 jets, and the Saab 340 and 2000 regional turboprops—continue to use them today. On a high-utilization commercial airliner, first-generation carbon brakes, he says, are good for about 1,000-2,000 landings—or about one year of service.
“We recycle two worn carbon heat sinks to create one new heat sink,” Crampton notes. “When the worn carbon brakes are sent back by our customer, we inspect the heat sink for weight loss, oxidation damage and unusual wear patterns in the discs. We then determine if there is enough integrity left for them to be refurbished.”
To do that, the worn discs are put into a furnace where they undergo carbon vapor deposition (CVD) enhancement, during which carbon atoms are deposited onto the discs to restore density to a usable level. Prior to reassembly, a proprietary coating is applied; the result is a single new heat sink from old parts that otherwise would have been thrown away.
Since the 1990s, Meggitt has developed a new generation of carbon brakes good for 2,000-3,000 landings on short- to medium-range transports such as the Embraer 170/190 regional jets, and the new Bombardier CSeries.
For modern-generation carbon brakes, Meggitt developed a new recycling approach, which it calls “Thick/Thin Refurbishment.” This method, Crampton says, has some similarities to the Two-For-One approach, but with one important difference: “It eliminates the CVD enhancement process due to modern carbon brake technology capabilities,” he points out. “By eliminating the furnace, we take away a very time-consuming step in the recycling process that requires technicians to make multiple visits to the furnace in order to build up the disc’s required thickness. The process can literally take several weeks, whereas the Thick/Thin process can be done within a few days.”
With the Thick/Thin method, the thin rotors and thick stators are inspected for any unusual damage that would cause them to be discarded. If salvageable, the thick stators are machined to create new, thin disks that then go back into service as new rotors, following application of a proprietary oxidation coating.
“As with the Two-For-One process, the Thick/Thin process provides major savings with respect to scrap, because you are reusing as much as you can,” says Crampton. “But since no furnace is involved, there is a tremendous savings in electricity and CO2 emissions.”
Recycling, when possible, need not be limited to high-value, reusable components. Stephen Lim, president of VT San Antonio Aerospace, Texas, reports that the company, which specializes in aircraft teardown, is targeting partner companies to realize greater salvage value from end-of-life aircraft. VT San Antonio Aerospace is an affiliate of ST Aerospace.
“Traditional aircraft part-out is not very efficient, because a big chunk of the aircraft is discarded at the end of its life cycle,” says Lim. “But we are putting a process in place to extract the maximum value when an aircraft is disassembled.” He adds that with removal of the engines, landing gear, APU and the high-cost components, about 50-75% of the hull is generally recyclable. It’s the portion that is chopped up and goes into landfills that has attracted the company’s focus.
“ST Aerospace is working with vendors to set up a process in which various kinds of material can be segregated and more easily recycled, rather than thrown away,” Lim points out. Clients have expressed interest in specific recyclable items, such as copper wiring or aluminum. Lim suggests that the only material that will go to a landfill is the “fluff,” such as carpeting, floor panels and waste insulation.
“It is safe to say that only about 10-15% of this type of material will be remaining, provided the interiors are removed,” he says. “The goal is to extract as much value as possible from aircraft. Nobody, to my knowledge, has looked at this to the extent that we have.”
Lim reports that the incentive for pushing the boundaries of aircraft recycling is the number of anticipated airframe retirements over the next 10 years. “Estimates are that as many as 1,000 aircraft per year will be retired over that period,” he says. “With numbers of that kind, it means that there is a critical mass for us to explore a business case for recycling more of an airframe than we have in the past.”
ST Aerospace, Lim says, is developing the framework for the program and establishing best practices guidelines. The company has targeted the end of the first quarter of 2015 for implementation at its Hondo Aerospace facility in Hondo, Texas. “We are focusing on Hondo to provide a proof-of-concept for this innovation in recycling. If that proves viable, we would be able to transfer the know-how to other facilities in the ST Aerospace Group.”
Lim adds that the company is seeking accreditation for this as a green recycling process, which could generate carbon credits for its customers. ST Aerospace has incorporated the Aircraft Fleet Recycling Association’s Best Management Practices guidelines in its processes, and all requirements will be in place by the first quarter of 2015 for green part-out and aircraft accreditation at Hondo Aerospace.
Bob Nichols, chief operating officer of Miami-based AerSale, argues that the most efficient, profitable, and environmentally responsible way of tearing down an aircraft is to salvage the utility of higher-value assemblies. “We can lease off-engine green [remaining] time for parked aircraft during [airline industry] down cycles, and can return to resurrect their airframes years later when markets recover. Alternatively, we can remove climate-controlled and hazardous items, while picking off the airframes for years to come.”
This, says Nichols, enables the airframes to be used as self-contained parts bins. “This avoids adding to the collective millions of dollars wasted by our industry for expenditures on unnecessary disassembly, identification, transport, and packaging of items that are never sold.”
Not surprisingly, the highest demand for components—such as avionics, wheels, brakes, landing gear, and engine line replaceable units (LRU), “directly correlates to unit failure and the expiration of useful life. Many of these parts are harvested from relatively young airframes, as new engine technologies accelerate retirements. “These aircraft embody advanced technology avionics and components that will be utilized even on in-production aircraft for years to come,” he says.
AerSale maintains a 500-aircraft storage facility at Roswell, New Mexico, where hazardous materials, such as fuel and lubricants, are also reused. “Usable fluid, such as leftover fuel, is recycled to ferry aircraft and perform on-wing engine performance testing, or to power our ground-support equipment; or we will sell it for reuse by the local agriculture industry,” adds Nichols. “Also, valuable lubricants are collected and sold for recycling to help defray further aircraft recycling costs.”
Gallery See some of the major environmental threats posed by MRO activities:
A version of this article appears in the December 1/8 issue of Aviation Week & Space Technology.