Business & GA, Commercial, Military

Product Focus: Wire and Cable

By Barry Rosenberg | November 1, 2008
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The mantra for designers and manufacturers of avionics-grade wire and cable is to do more with less.

The "more" relates to the bandwidth capability and throughput that make it possible for airlines and corporate operators to load their in-flight entertainment (IFE) systems with more movies, more music, more games and more connectivity. The "less" means developing smaller gauge wires and cables that have the same or better throughput capacity of existing ones, and weigh less because they’re thinner. That means using different materials for the dielectric and jacket, and alternate materials like Teflon-type wraps that reduce weight while having good transmission properties.

Shielding becomes increasingly important in reducing crosstalk as gauge goes down, especially in airline applications where passengers are sitting one seat apart from each other and using the IFE system in the seatback in front of them to watch different things.

"What’s driving the industry is the migration of consumer electronics into aviation," said Ray Frelk, vice president of sales and marketing for ECS, Franklin, Wis. "The application is similar to what it’s always been; putting video signal down a wire isn’t new. What is new is putting multiple types of input down the same cable. The challenge lies in marrying that with speed, increased memory capacity and the desire to have a smaller pipe with lower weight and greater capacity."

And while that challenge is being met, wire and cable engineers also have to address a new FAA Part 26 regulation approved late last year that redefines wire as a system in of itself. The mandate is an enhanced airworthiness program related primarily to inspection and maintenance that now refers to wiring networks as an Electrical Wiring Interconnection System.

"Under the mandate we have to do a zonal analysis of the wiring in an aircraft," said Matt Higgins, aerospace engineer with Emteq, New Berlin, Wis. "The analysis has to include wire routing, installation, possible contamination from various fluids like hydraulic fluid — not just flammability. And if you do maintenance with a drill, you have to take into account metal shavings that might fall on the wire."

What that does for companies like Emteq, which designs and assembles wire harnesses, is complicate the supplemental type certification (STC) process for aircraft upgrades. It also increases the cost of doing the work. Said Higgins: "Before we took into account damage tolerance and made sure wire was installed in a safe way. But now we have to prove that to the FAA."

Copper and Fiber

The desire to push more and more data down the pipeline will eventually lead to more widespread use of fiber optic cable instead of copper. Cable television companies like Time Warner are leading the way in the transition from coax to fiber, and many customers in places like New York are seeing fiber come right to the house.

In aviation, though, it’s going to be a few more years before fiber extends to the seatback.

"They’ll eventually be a flip flop between fiber optics and copper," said Tony Forst, applications engineer with Emteq. "Copper is ruggedized, but fiber optic will give you the performance. But for seat-to-seat applications in a Boeing aircraft, fiber is not rugged enough." That’s particularly true because of the abuse sustained by under-seat IFE boxes, which are regularly kicked and have drinks spilled on them. "Copper weighs more, but as long as copper keeps advancing people will stay with it," Forst said.

It is the desire to reduce weight that is driving much of the wire and cable industry, with companies like Emteq recently introducing new, lighter weight coaxial cables that save weight compared to conventional RG and Mil-C-17 cables. According to company literature, Emteq’s lighter-weight cable can save anywhere from 9.5 pounds on a business jet (savings based on 340 feet of coax antenna cable) to 157.6 pounds on a regional transport (savings based on 1,271 feet of cable).

"Our competitors use a lot more shielding," said Higgins. "We use just a couple shields that are higher performance. We optimize the materials we are using."

Those are technical issues, ones that can be overcome with time and are, in fact, the sort of challenges that avionics engineers look forward to. Another challenge for the wire and cable industry, though, is not one that can be necessarily addressed with smarts. That’s a realignment in OEM priorities that has led to a shift away from designing for functionality to designing for expediency.

"Engineering departments have been hit hard in many cases," said Frelk. "They don’t have the specification engineers that they used to have. Now they have smart, packaging engineers who take systems designed for home use and put them into boxes that fit the proper form factors."

What that means is that wires that might only run three feet between a DVD player and the television in a home setup have to, instead, run 40 to 50 feet in an aircraft. Maintaining wire in an aviation application when its original design configuration was derived from commercial electronics is a recipe for maintenance problems down the line, according to Frelk.

"We find that the people doing the packaging don’t take into consideration the environment in which the cable will be used," he said. "We end up with shorter development cycles in which the product is practically ready to be installed and we haven’t delivered the type of cable needed to make it work."

While many other suppliers of aircraft components and systems are now being brought into the design process by OEMs earlier than ever before, it seems to be a trend that has bypassed suppliers of wire and cable.

The design of electronic flight bags (EFB) is an example of a cockpit system that, in some instances, doesn’t take wiring into account. The tablet itself typically has a wire bundle coming out one side of the EFB. Designers forget, though, that both the pilot and co-pilot have an EFB, so the wire bundle that exits the EFB at the left seat might be unobtrusive, but when it is installed at the right seat, the bundle exits in a clumsy fashion.

"Designers are shocked at the size of the cable they see coming out of the box," said Frelk. "There’s a growing gap in the industry in terms of a technical understanding of what it takes to wire up new systems in aircraft, particularly in understanding the type of product that needs to be installed, its connection, termination, and the size and weight of the bundle. It should be part of the initial design, not an afterthought."

As an aside, the growing acceptance of EFBs is looked at as a distinct, new market for the wire and cable industry. Many EFBs are installed into a fixed mount, but many of them are not and can be adjusted by the pilots. That movement necessitates the use of a coiled cord to maintain the integrity of the wires within. It is that coiled cord that is a whole new product for the industry.

As IFE systems get more complicated, improperly specified or installed wires can result in major troubleshooting headaches for manufacturers of IFE equipment, and in unhappy passengers in the case of airlines, who have to explain to a frequent flier why his seatmate can watch the movie "Rocky" while his screen remains dark, with nothing but Sky Mall magazine for entertainment.

"The IFE manufacturers are swamped trying to put more capability in front of passengers, and the cable assembly is not even a consideration," said Frelk. "Who’s going to spend time redesigning a $79 wire bundle? It’s hard for them to live with the consequences, though."

Wire and cable companies can help themselves by getting involved in standards-setting organizations like ARINC, so that when new standards for avionics are promulgated they take into account things like cable installation and survivability.

"Our challenge is to get into the front end of the design and to use the knowledge we have to prevent problems from occurring in the first place," said Frelk. "Nobody wants to deal with the problem after the fact."

They can also address the issue by making sure that installers know their job. "The biggest challenge isn’t with wire and cable; it is with training people for installation techniques," said Higgins. "With coax you need the proper connectors on the end and you can’t tie it in a knot. We have to remind installers to adhere to the instructions."

It might seem logical to assume the wire and cable industry would fear their market would slowly be eroded by wireless connections. Not only is that not the case, the wireless revolution has helped, in some ways, to revitalize the traditional wire and cable business.

"We play a big part in the wireless movement," said Higgins. "You might have a wireless box, but you still need a wire that goes to the box and you need another going to the wireless antenna, so for the wire and cable business it has been a big boost because of all the equipment that runs wireless today."

Avionics Magazine’s Product Focus is a monthly feature that examines some of the latest product offerings in different market segments of the avionics industry. It does not represent a comprehensive survey of all products in these markets.

Market Moves
–– Wire and cable distribution company WireMasters, based in Columbia, Tenn., anticipates double-digit growth this year. The company recently broke ground on a facility expansion, giving it needed capacity to keep up with business.

WireMasters CEO David Hill said he started with the company in 1991 as one of about eight employees. At the time, the company stocked about $500,000 in inventory, with $9 million in annual sales. Since then,

WireMasters has grown to more than 90 employees, stocks about $7 million in inventory and is on target to reach $60 million sales this year, Hill said.

WireMasters ships about $4.5 million to $5 million of inventory each month, which translates to about 50 million feet of wire and cable.

“I’ve really focused on customer service and quality and really tried to make our company different from the rest in that we are small enough that we still want to talk to you on the phone and we still want to take care of you like you’re our only customer. So I really do think that’s made a difference in how we are able to grow,” Hill said in a telephone interview.

The company moved into a 46,000-square-foot facility in October 2007, and it is beginning a 20,000-square-foot expansion to the facility expected to be completed this year.

“We feel like we’re in a recession-proof business,” Hill said. “The next five years I do project to be the best five years of the industry … It is my goal within the next five years for WireMasters to be a $100 million year sales company.”
WireMasters customers include Lockheed Martin, Airbus, Boeing, Bombardier, Northrop Grumman, Sikorsky, UPS, FedEx and BAE Systems.

Carlisle Interconnect Technologies, formerly Tensolite, this year introduced the “LITEflight EP” (Enhanced Performance) family of aerospace grade fiber optic cables. Carlisle said the cable series features lower loss, tighter bend radius, improved thermal stability and better handling during termination and installation than earlier versions. LITEflight EP is available in multiple sizes, configurations and temperature ratings to 260°C.

SEA Wire and Cable, Madison, Ala., a distributor of Mil-spec wire and cable products, in September unveiled its “E-wire” online logistics system. The system allows 24-hour access to the company’s line of wire harness products, and allows customers to place, expedite and check on orders, track shipments and check inventory. In June, SEA Wire and Cable launched the “Product Wizard” service to its Internet portfolio, which allows users to configure Mil-spec wire and cable. The service utilizes a propriety database, which ensures users will select the correct wire and cable for their aircraft.

Tyco Electronics this year introduced D-200 MiniSeal Crimp Splices, which combine a nickel-plated copper crimp barrel with a separate, heat-shrinkable, transparent sealing sleeve. Tyco said the splices can be used to seal and protect high-temperature rated wires with Teflon insulation. The splices prevent the penetration of liquids and the resulting chemical and galvanic corrosion and potential short circuits, the company said.

Emteq, New Berlin, Wis., in May formed a partnership with Cable Technologies of Montana, of Great Falls, Mont., with the goal of strengthening its electronic assembly and integration work.
Emteq said the partnership will give it access to additional cable and harness assembly capacity, which will be beneficial for forward-fit and aftermarket process and assembly work, as well as expand its product and service offering to the military market.


A.E. Petsche Co.
AeroFlite Enterprises
Air Harness Manufacturing
AirWorks Inc.
Ametek Aerospace
Amphenol Corp.
Brand Rex
Calmont Wire & Cable, Inc.
Carlisle Interconnect Technologies
Chippewa Aerospace
Christensen Industries
Cirris Systems Corp.
Dallas Avionics Inc.
Data Bus Products
DIT-MCO International
Eaton Corp.
Electro Enterprises, Inc.
Glenair Inc.
Habia Cable
Hollingsead International
H.S. Electronics Inc.
InterConnect Wire
kSARIA Corp.
Marine Air Supply
MilesTek Corp.
Phoenix Logistics
PIC Wire & Cable
SEA Wire & Cable
Teledyne Reynolds
Thermal Memory Ltd.
Tri-Star Electronics International
Tyco Electronics
Vermillion, Inc.
W.L. Gore
Woven Electronics Corp.
Zippertubing Co.

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