Business & GA, Commercial, Military

LCD: Bigger Than Ever

By David Jensen | November 1, 2001
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If all goes as planned, the aviation industry will see the largest primary cockpit display on the market in March 2002. The liquid crystal display (LCD) will measure 12 by 9 inches (30.5 by 23 cm), or 15 inches (38 cm) diagonal, a familiar format to passengers who use large laptop computers. The display was designed primarily for the retrofit market (though it is available to original equipment manufacturers) and will replace many of an aircraft’s mechanical cockpit displays. It also will display other data, such as weather radar and ground terrain maps. And, from a Jeppesen database of airports, the integrated display even will present the aircraft’s movement along runways and taxiways to help prevent runway incursions.

The company that developed this large display is located just outside of Philadelphia, a number of musket shots away from where the United States’ founding fathers signed the Declaration of Independence. Some independent thinking went into this new display and into the manufacturer’s other products, but company officials prefer the word "innovative" to describe their technologies. The company’s name is Innovative Solutions & Support (IS&S), in Malvern, Pa.

IS&S’ other products are quite diverse, from air data systems for reduced vertical separation minima (RVSM) to engine and fuel instrumentation to onboard wireless local area networks (LANs). The firm employs 110 people and has just moved to a new engineering and manufacturing facility that covers more than 60,000 square feet (5,574 square meters) of space.

Starting with the Military

IS&S was founded in 1988, largely to develop products for military aircraft upgrades. Its first large contract was to provide U.S. Air Force and Navy aircraft with a solid state barometric altimeter. The Air Force gave IS&S its largest contract to date for triplex RVSM products for the KC-135 upgrade. Awarded in 1997, the contract called for more than 600 shipsets for a 585-aircraft fleet.

"We started developing products for upgrade in the military," says Geoffrey Hedrick, chairman, chief executive officer (CEO) and founder of IS&S. "Then we took those products and applied them to commercial use, for air transport and bizjets." Today, some 40 percent of IS&S’ business remains with the military, but an equal amount comes from the corporate aircraft market, and about 20 percent is from the air transport market.

IS&S executives are not prepared to say whether their new large cockpit display will enter the military or the civil market first. Called the Pilot’s/IP (IP stands for "information portal"), the display is being tested on the company’s Pilatus PC-12. It has been certified to RTCA DO-160D (environment and high-intensity radiated field, or HIRF) and FAA AC20-136 (lightning) standards. The software has been approved to the DO-178B standard

Keeping Cool Naturally

"It’s ideal for retrofit," Hedrick claims. "Most LCDs use 70+ watts of power and the CRTs [cathode ray tubes] need about 100 watts, so they require redundant forced air cooling–with all the motors and fans and ducting, weighing at least 500 pounds [227 kg]–because if the cooling stops, eventually the display stops. But ours does not need cooling." The Pilot’s/IP screen requires just 22 watts of power; the accompanying symbol generator requires 45 watts.

"The display was designed to be a retrofit system for airplanes, whether they have a cooling system installed or not," Hedrick adds. "We designed a display that is sunlight-readable but requires very low power."

Exactly how IS&S designed a low-power display is proprietary. However, Hedrick says the secret is in the glass. Essentially, the company acquires pieces of glass made for laptop screens and then refines them. According to Hedrick, the glass is "nano-machined for extremely low reflectance."

The challenge is to make a screen’s spectral reflectance as low as possible (no more than 1 percent), because the larger the percent of spectral reflectance the greater the backlight intensity required to make the display legible. According to David Marvin, IS&S’ vice president, marketing and business development, the spectral reflectance on the Pilot’s/IP is less than 0.5 percent.

Low illumination can diminish image clarity, another challenge that IS&S faced. "We find that the higher the pixel count, the dimmer the display, and that’s a problem," says Hendrick. "Our pixel count is roughly 100 per square inch. It’s an optically efficient display." The Pilot’s/IP is quite readable and offers viewing angles of +/- 80 degrees horizontally and +80 to —55 degrees vertically. "Right now we are working on it also being NVG [night vision goggle] -compatible," Hedrick reports.

The Pilot’s/IP also is quite easy to install. "It’s only 3 inches [7.6 cm] deep, so there are no interference issues," says Hedrick. "Certain aircraft can be modified with the display within eight hours. You simply remove the aluminum panel that has the existing instruments and replace it with a panel that has a new cut-out for the display." The sensors, once connected to the individual instruments, are plugged into the Pilot’s/IP’s symbol generator. The serial communications ports are available in the RS422, RS232 or RS485 standard protocols.

"We developed an interface box that converts analog signals to digital," Hedrick says. "But anyone upgrading an aircraft probably would want to also install newer, digital instrumentation."

The glass market dictated the screen size for the Pilot’s/IP. The relatively low number of glass pieces required by the aviation industry can make custom sizes cost-prohibitive. So IS&S selected a laptop screen size that is produced in high volumes, reducing the per-glass piece price.

A large glass size that is specially engineered could pose problems in the high-vibration environment that exists in some aircraft. Nevertheless, Hedrick says the Pilot’s/IP meets the Federal Aviation Administration’s (FAA’s) standard. IS&S has yet to have a Pilot’s/IP fail and feels it is conservative in giving the display a 25,000-hour mean time between failure (MTBF).

What the Pilot Sees

The display on the Pilot’s/IP can replace six primary instruments: airspeed, attitude, altimeter, vertical speed (also called rate of climb), horizontal situation indicator (HSI), and radio magnetic indicator (RMI). The display system weighs about 16 pounds (7.25 kg)–6 pounds (2.72 kg) for the screen and 10 pounds (4.53 kg) for the symbol generator. "That’s about a fifth the weight of the six instruments it replaces," says Hedrick.

No button pushing through menus is required to view the different instrumentation; the Pilot’s/IP is large enough to show all instrument faces on one neatly arranged display. On the navigation display on the lower half of the screen, the pilot can overlay weather radar and Traffic Alert Collision Avoidance System (TCAS) displays.

IS&S, which develops all software for the Pilot’s/IP, is working on another display for the large LCD, which will provide a moving-map runway guidance system. The pilot would activate the display manually, on half the screen, by adjusting a switch on either a cockpit control unit or the Pilot’s/IP. All instrument displays remain on the other half of the screen, but smaller in size. Fail-safe programming would make sure that the surface map appears only when the aircraft is on the ground. "It won’t switch over if the aircraft is above a certain speed and altitude," says Hedrick.

On the projected airport surface chart, taken from a Jeppesen database, the pilot can view a symbol of his aircraft as it moves along the runway and taxiways. Positioning data would come from an existing Global Positioning System (GPS) or a GPS card inserted into the display processor.

Pilots control the display in two ways, says Marvin. They select weather radar, radio frequencies, etc. using a conventional electronic flight instrument system (EFIS) control panel. The Pilot’s/IP also includes a touch strip along the side of the screen. Working like a computer mouse or a laptop touch pad, the touch strip allows the pilot to move a cursor and zoom in on parts of the Jepp approach charts.

"The pilot won’t have to look at the small lettering of a chart resting on his knee," says Hedrick. "This display will help prevent runway incursions. In poor visibility, he’ll be able to see where he should be and where he should stop on the taxiways."

How much will the Pilot’s/IP cost? An exact price will accompany the display’s debut in March, but Marvin says its price tag will read less than $100,000 per system.

Ready for RVSM Retrofit

Gradually, reduced vertical separation minima (RVSM) is being applied worldwide. The increased number of flight levels brought about by reducing vertical separation from 2,000 feet to 1,000 feet exists on air routes across the North Atlantic and Pacific. RVSM is being implemented along the Western Atlantic down to the Bahamas this month and will apply over Europe, beginning in January 2002 (see chart, opposite page).

Few companies will capitalize more on this means to increase airspace capacity than Innovative Solutions & Support (IS&S). Five years ago, it produced an RVSM package for DC-8s operated by air cargo carriers. In 1997 IS&S developed unique, triply redundant, RVSM-compliant instruments for the U.S. Air Force KC-135 cargo aircraft. Claiming IS&S is "probably the largest retrofitter of RVSM instrumentation," Geoffrey Hedrick, company chairman and CEO, says his firm produces a range of products for RVSM, "from tiny modules to full-blown digital air data computers." IS&S has obtained RVSM instrumentation approvals on 15 aircraft types and has delivered more than 1,500 RVSM systems.

Regulations throughout the world require redundant RVSM systems, each of which includes two independent altimetry systems, an altitude reporting transponder, altitude alert system and automatic altitude control system. If one air data system goes down or the two systems don’t agree, the aircraft must exit the RVSM airspace. With IS&S’ triplex system, one system’s failure will not prohibit flight in RVSM airspace, says Hedrick. Redundancy remains.

The triplex system does not comprise three independent systems. That would be cost-prohibitive. Rather it includes two altimeters and an air data computer. All self-sensing, they act in combination as independent air data computers, continually monitoring their outputs. A sensor failure will be indicated on the altimeter. Connected to the aircraft air data sensors and equipped with their own internal transducers, the altimeters compare self-sensed data with that from the digital air data computer (DADC).

Dual-redundant systems also can be installed. In this case two systems can shut down or be in disagreement and there still will be redundancy and the ability to conitinue in RVSM_airspace.

Smaller Displays

In addition to the large Pilot’s/IP display, Innovative Solutions and Support Inc. (IS&S) produces displays in more familiar sizes, including for airspeed, altitude, air data and fuel quantity. All of the displays are digital and all offer at least 30,000 hours’ mean time between failure (MTBF).

The mach airspeed indicator and air data display both have self-sensing modes, which are used to make IS&S’ reduced vertical separation minima (RVSM) packages redundant. The feather-light fuel gauges weigh less than 1 pound (0.45 kg) and, since the indicator and totalizer have a single part number, are easy to maintain.

A new entry in IS&S’ product line is a 15-inch (38-cm) -diagonal cabin entertainment display, which is comparable to, though not quite so good in quality as, the Pilot’s/IP. The first cabin display was delivered in September to a corporate customer flying a Gulfstream jet.

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