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Sunday, January 1, 2012

Cockpit Switches

The proliferation of touchscreen display technologies is changing the role of traditional push-button and rotary switches in the cockpit

By Ed McKenna

The growing influence of digital electronics on the flight deck is driving switch developers back to the drawing board. Already ceding territory to liquid crystal displays (LCD), traditional rotary and push button switches must now contend with new touchscreen panels being rolled out. Still in an early phase, touch technology is, in a way, changing the definition of the cockpit switch. In response, switch companies are broadening their offerings and introducing smaller, more capable components to compete for their place in the changing cockpit.

Most industry experts concede that traditional mechanical cockpit switches, especially those used for key safety functions such as deploying landing gear, are not going away any time soon. However, “the days of the Boeing commercial cockpits with 200 discrete switches overhead and all around you” are passing with arrival of multifunction panels with “the ability to take a whole bank of switches and consolidate their functions into a multifunction box,” said Terry Trumbull, vice president of Electro-Mech Components, based in South El Monte, Calif.

Last summer, Rockwell Collins gave a boost to the touchscreen movement introducing what it called the industry’s first touch-control primary flight display for business jets and turboprop aircraft. Available on the company’s Pro Line Fusion integrated avionics suite, the technology is slated to be certified in 2013, according to Adam Evanschwartz, principal business development manager for commercial systems at Rockwell Collins.

While targeting smaller business aircraft, the system will initially be retrofitted into Hawker Beechcraft King Air aircraft with Rockwell Collins’ Pro Line 21 avionics. Evanschwartz said he sees “market interest in touchscreen technology across all of commercial aviation.” The technology offers OEMs and cockpit designers the flexibility to “make tradeoffs between physical switches … (and) touchscreens.” In its current offering, Rockwell Collins is providing physical switches as backups, but just having a touchscreen allows OEMs to save cost and simplify installation by integrating functions previously performed by federated buttons, he said

For the pilot, the benefits begin with ease of use, Evanschwartz said. “Our touchscreen displays are the primary flight displays and the multifunction displays themselves … (so) by interacting directly with the screens, the pilots’ eyes and hands are (focused) on the same exact place on the system making it easier to use.”

Touch technology “simplifies the operating environment” and allows pilots “to accomplish what (they) need to accomplish more quickly,” said Jim Alpiser, director of aviation aftermarket sales and marketing at Garmin. The company introduced the technology on its G3000 integrated cockpit system and is using it on GTN 650 and 750 products and its forthcoming G5000 system.

Unlike Rockwell, Garmin uses a touch controller for its primary flight display and the multifunction displays that “is ergonomically designed to go into a pedestal area and be almost down toward your knee or … the side of your body,” said Alpiser. “It is a very natural place to interact with the unit,” which has a “wide rubberized bezel on it … (giving) the pilot something to grab on to.” For its more retrofitable GTN 650 and 750 panels, Garmin tackled the challenges of integrating into the less user friendly traditional avionics stack by building “a stabilization rest at the bottom of the unit” for pilots to anchor their hands on very naturally, said Alpiser.

“We have alternate data entry for most of the core functions … (so) you can still do a more traditional cursor knob,” he said. But the company chose not to “replicate every single button with a hard button.”

“We are still pretty early in (bringing) touch controls into the cockpit,” said Alpiser. That said, the company is already targeting the larger Part 25 aircraft market commercial airline market with its G5000 product. However, Alpiser acknowledges with all the stakeholder issues involved, the G5000 may be “multiple years away from getting its certification for an aircraft partner under its belt.” These issues are “why you are seeing it come into the smaller end of general aviation first,” he said. The Cessna Citation Ten will be one of the first aircraft programs to use the system.

Future of Switches

Even in this early phase, it is clear the technology will have a significant impact on traditional cockpit switches. “Certainly some of the avionics switches can be consolidated,” said Evanschwartz. It can perform, “for example, some of the functions in flight that are not used commonly like HF radio tuning and setting the HF radio’s properties … and changing the default avionics settings like the attitude director indicator on the screen.”

In the longer term, the technology “when paired with the right airplanes systems can also be used to replace or augment other system switches beyond the avionics,” he said. “You can imagine using virtual touch panels for fuel … (and) electronic system control.” Also, “environmental control, cabin temperature, lights (and) pressurization … seem to be easy targets for integrating into a touchscreen controller.”

Traditional, dedicated switches would, however, continue to be used to control many flight safety functions, such as landing gear, master caution warning, fire fighting and some of the communications, said Craig Morgan, vice president of sales at Aerospace Optics, based in Fort Worth, Texas.

“Touch is really controversial issue: nine out of 10 pilots that you approach … prefer to have a traditional tactile type response as opposed to touch, but at the same time, they will admit touch has utility and value because ultimately it reduces the pilot workload and improves the human factors,” Morgan said.

Even with this building momentum, questions about broader use of the technology remain, centering mainly on issues related to usability and turbulence.

“It’s clearly making in-roads and does indeed have a place but has some significant downsides as well,” said Bruce Maxwell, president of Luma Technologies, based in Bellevue, Wash. “Time will tell what the ultimate configuration and acceptance will be.”

While they do not offer the same feel or assuring click of mechanical switches, the systems do have built-in safeguards to prevent errors. For example, both Garmin and Rockwell’s systems require to pilots to not only select an action but also confirm it in an additional step.

A separate issue for the Rockwell Collins system “is insuring that pilots can reach the displays,” said Evanschwartz. While not an issue in the lighter business aircraft, pilots “would really have to move forward in their seats to reach” the displays on larger aircraft. Retrofit of such aircraft would likely require reconfiguring cockpits. “Certainly on clean sheet aircraft programs, we can design a cockpit to accommodate.”

When it comes to turbulence, Garmin touts the design characteristics of its touchscreen controller with its wide “rubberized bezel” providing pilots something to grab onto and stabilize their hands when operating in turbulence. “We did hard work and did a lot of research and a lot of user testing as well to see what is the potential way to alleviate those concerns,” said Alpiser.

“The fact is that during the typical corporate aircraft or airline flight, you are not changing display configurations that much, so there is virtually no case to be made for touching the displays during turbulence,” Evanschwartz said. However, “our displays are activated on release, so you can stabilize your finger by pressing right on the display, (and then) it doesn’t activate or select anything until you take it off,” he said. The system also includes mechanical backups.

Garmin and Rockwell are by no means the only companies building touchscreen displays. There are growing number of companies offering displays designed to boost operations in existing cockpits. For example, Honeywell and Aspen Avionics have developed the Bendix/King KSN 770, a multi-function touchscreen display for general aviation customers.

“Many pilots will find this approach much more attractive than replacing a full cockpit suite to get the same functionality from Garmin,” said Rob Wilson, president of business and general aviation at Honeywell Aerospace.

Ducommun LaBarge Technologies introduced its touchscreen Multi-Input Interactive Display Unit (MIDU). “Our unit is basically like a Swiss Army knife: it can do a lot of functions,” said Daniel Auh, the company’s business development manager HMI. The ARINC 615/615A, ARINC 739 and ARINC 717 compatible system allows the crew to interact with a number of subsystems, including Aircraft Data Loading (ADL), satellite communications, the Aircraft Communications Addressing and Reporting System and Aircraft Condition Monitoring System. “We are currently marketing the system to the airlines” as a replacement for older technology and a way to reduce the number of line replaceable units in the aircraft, Auh said.

Meanwhile, Aerospace Optics is responding to the proliferation of multifunction displays with its VIVISUN Multi-Function Body (MFB) switch series that allows for components to take on additional functionality. One example would be a push button switch “that could function as a rotary switch, so you would have to functions in one,” said Morgan. In addition, cockpit designers are asking to incorporate typically external functions, such as an edge detector or “even a latching relay that they would normally hang somewhere in the cockpit” into a discrete multifunction switch.

Electro-Mech Components offers an “audio control rotary potentiometer switch with a push switch combined,” said Trumbull. Feedback from the pilots has been very positive. “They like the tactile feedback of the push switch.”

Meanwhile, companies, such as Luma Technologies, are expanding the potential uses for their products. The low profile LT-2000 Series switches, designed mainly for cockpit terrain awareness systems, are now being used for applications including “autopilot control panels for helicopter and fixed wing aircraft, rail/locomotive display systems,” said Maxwell.

Along with versatility, there is still the strong industry trend to produce smaller, more compact and lighter components, said Trumbull. “Our typical switch is a half-inch square in width and height although we do some that are three-eighths square inch,” he said. “That is pretty compact if you are talking about discrete functions.” There is also a push to shorten the depth the component extends behind the cockpit panel. “We go to maybe three-quarters of an inch behind the panel, but that is about it; we can’t get much shorter … (because it will) then affect mechanical travel of the buttons.” The need to shorten is being mitigated by the implementation of the multifunction displays, which can extend “an inch to an inch-and-a-half behind the panel, he said.

Meanwhile, industry continues its transition from incandescent to LED lighting for its switch components. In retrofit, the main holdups are costs and complexity. The investment can be very significant because it involves “not just replacing the light bulbs but changing the whole system: the interior the wires, the drive packages, the CMMs and operation manuals it is a very significant change,” said Auh. The solution would be to develop an LED technology that allows for “plug-and-play with the incandescent system” eliminating the need to change the existing wiring, he said.

In the future, the lighting will be addressed using an “integrated backplane approach, such as used on the 787 and HondaJet,” said Maxwell. In this approach, “all switches mount to a single or multiple backplanes which greatly cuts down on wiring,” he said. Furthermore, you can “take this to the next level and … do something like an Ethernet so the switches are now communicating with whatever remote system they are controlling electronically,” he said. At that point, the lighting system is operating “like an internal Ethernet sending multiple signals over or on just a few lines versus the 16 (wires) per switch used by the traditional legacy style of wiring.”

Next month: Connectors

Avionics Magazine’s Product Focus is a monthly feature that examines some of the latest trends in different market segments of the avionics industry. It does not represent a comprehensive survey of all companies and products in these markets. Avionics Product Focus Editor Ed McKenna can be contacted at emckenna@accessintel.com.

Market Moves

The following are new products introduced by manufacturers of cockpit switch products.

➤ Astronics Corp., of East Aurora, N.Y., in October was selected to supply illuminated instrument panels for Cessna Aircraft’s Citation M2, Citation Ten and Corvalis TTX aircraft as well as exterior lighting for the Citation M2 and Citation Ten.

➤ Zodiac Aerospace, through its ECE Company in France and IDD Aerospace in the United States, completed development and certification of various LED flight deck controls and systems for the Gulfstream G650, the company announced in October. The shipset includes the subsystem for the lighting dimming controllers as well as the Systems and Equipment Overhead Control Panels that are the interface between pilots and onboard systems.

➤ Staco Systems, based on Irvine, Calif., in June said it was selected to provide an 88-key panel mount keyboard designed for use in an aerial surveillance system for a primary European customer. The keyboard can be integrated into the control console of many applications such as the air systems and simulators.

This keyboard will feature an embedded design for green LED backlight illumination and five-level dimming features. It is rugged, rated IP65 waterproof compliant and meets MIL-810 and MIL-461 specifications, the company said.

Companies

Aerospace Optics www.vivisun.com

Ametek Aerospace www.ametek.com

Avionics International Supply www.avionicsinternational.com

Astronics Corp. www.astronics.com

Avtech Corp. www.avtcorp.com

Cole Instrument Corp. www.cole-switches.com

Crane Aerospace & Electronics www.craneae.com

Dallas Avionics, Inc. www.dallasavionics.com

Ducommun Technologies www.ducommun.com

Eaton Corp. www.eaton.com

Electro-Mech Components www.electromechcomp.com

Electro Switch Corp. www.electroswitch.com

Esterline (Leach, Korry) www.esterline.com

Flame Enterprises www.flamecorp.com

HS Electronics www.hselectronics.com

Interface Displays and Controls www.interfacedisplays.com

Luma Technologies LLC www.lumatech.com

Marine Air Supply Co. www.marineairsupply.com

Panelight Components Group, LLC www.panelightcomponents.com

Peerless Electronics www.peerlesselectronics.com

Spectralux Corp. www.spectralux.com

Staco Systems www.stacosystems.com

TE Connectivity www.te.com

Teledyne Relays www.teledynerelays.com

Zodiac Aerospace www.zodiacaerospace.com

Aerospace Optics www.vivisun.com

Ametek Aerospace www.ametek.com

Avionics International Supply www.avionicsinternational.com

Astronics Corp. www.astronics.com

Avtech Corp. www.avtcorp.com

Cole Instrument Corp. www.cole-switches.com

Crane Aerospace & Electronics www.craneae.com

Dallas Avionics, Inc. www.dallasavionics.com

Ducommun Technologies www.ducommun.com

Eaton Corp. www.eaton.com

Electro-Mech Components www.electromechcomp.com

Electro Switch Corp. www.electroswitch.com

Esterline (Leach, Korry) www.esterline.com

Flame Enterprises www.flamecorp.com

HS Electronics www.hselectronics.com

Interface Displays and Controls www.interfacedisplays.com

Luma Technologies LLC www.lumatech.com

Marine Air Supply Co. www.marineairsupply.com

Panelight Components Group, LLC www.panelightcomponents.com

Peerless Electronics www.peerlesselectronics.com

Spectralux Corp. www.spectralux.com

Staco Systems www.stacosystems.com

TE Connectivity www.te.com

Teledyne Relays www.teledynerelays.com

Zodiac Aerospace www.zodiacaerospace.com

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