Guy Norris/PHOENIX Graham Warwick/CEDAR RAPIDS
Another busy day begins for the corporate-jet crew. Today's flight will take them from Dallas to New Orleans and on to Washington DC, weather permitting. The chief pilot moves the cursor to a "soft key" on the multi-function display (MFD) and selects weather mode.
Conditions en route are fine, but she is worried about the weather 1,000km (540nm) away, and how it might affect the afternoon's journey onward from New Orleans. Another cursor click and the latest weather-satellite picture of the eastern seaboard, datalinked to the aircraft, is displayed. She selects a close-up of the DC area and zooms in, ready to replan the flight if necessary - all using the cursor - but the weather looks okay.
A call from the cabin asks for more heat in the aft section. The co-pilot uses voice command to call up the utilities display. Using cursor and soft keys , he selects the environmental-control-system page, locates the right-hand air-conditioning pack and opens a valve by clicking the "mouse" with two taps of his finger.
It is time to review the approach chart for New Orleans. The commander can display the chart on the MFD, but, instead, chooses to call up the approach on the Pilot's Personal Assistant (PPA) - a portable, plug-in, device which resembles a personal computer. She must remember to take the PPA back tonight to draw up tomorrow's flight plan and check her email.
This scenario draws on the capabilities of Honeywell's latest Primus Epic integrated-avionics system for corporate aircraft. Similar outlines could be built around the abilities of Rockwell-Collins' competing Pro Line 21 system. What it illustrates is the potential of liquid-crystal displays (LCDs) to revolutionise cockpit management.
Collins introduced the first LCD-based avionics for corporate aircraft in 1995, when Raytheon Aircraft selected the Pro Line 21 system for its new Premier I light business-jet. Now, Honeywell is introducing the Primus Epic with a launch contract from Raytheon to equip its new Hawker Horizon "super mid-size" business jet.
Having scored their first successes, both companies are beginning to exploit the LCD's powerful graphics capability to answer some of the human-factors issues which have surfaced with today's "glass" cockpits, with their cathode-ray-tube (CRT) displays. They are applying "human-centred cockpit" design principles and using rapid-prototyping design tools to create and evaluate new display formats.
Active-matrix LCDs are digital devices with almost unlimited flexibility in what can be displayed, from maps and charts to weather-satellite images and external-camera video. They are half the size, half the weight, half the cost and consume half the power of CRTs, yet are twice as reliable. Use of commercial LCDs puts avionics manufacturers on a technology "fast-track" which is resulting in ever-sharper and larger displays.
There are disadvantages. A commercial LCD, when viewed from across the cockpit, would be unreadable. Optical compensation is needed to broaden the viewing angle to an industry-required minimum of 0¹/30¹vertically and +/-55¹ horizontally, for cross-cockpit viewing. Fluorescent backlighting which is stable, uniform and dimmable, with long lamp life and low heat output, must also be developed if an LCD is to be used in the cockpit.
Collins says that the choice of LCD technology is critical. There are two basic types, explains Bruce Ray, manager of flightdeck design: "naturally black" and "naturally white". A naturally black display offers a better viewing angle, he says, but is more difficult to produce and therefore significantly more expensive than the naturally white displays which make up the bulk of commercial LCDs.
While Honeywell has been building displays for the Boeing 777 using naturally black LCDs, Collins has been working with naturally white ones. Using commercial "glass" supplied by LCD manufacturer Sharp, the company has developed optical compensation which provides an "outstanding viewing angle-out to 90¹", says Ray. The advantage, he argues, is that naturally white LCDs are both cheaper and on the commercial-development fast-track.
Honeywell agrees and reveals that it, too, will use naturally white LCDs in the Primus Epic system. Displays director Bill Shelton says that the company plans to "-delay selection of glass for as long as possible, but you can safely say it will be an Asian supplier". Preliminary selection of an LCD supplier is planned for the first quarter of 1997, leading to delivery of pre-production displays in 1998. "We could have a prototype here by mid to late 1997," he says.
Both companies, initially, are developing the same size of display - 200 x 250mm. Collins will supply displays to Raytheon for the Premier I first flight in the third quarter of 1997, while Honeywell is working to the Hawker Horizon first-flight date of late 1999. The $3.9 million Premier I will have two displays as standard; the $14.5 million Hawker Horizon will have five.
Premier experience
Collins is re-engineering its design processes following experience gained developing the Pro Line 21 system for the Premier I. Increasing use is being made of rapid prototyping, to capture the customer's requirements and generate detailed specifications automatically before any avionics software is written.
The company has developed the VIVID (Visually Interactive Validation and Integration Domain), a computer-based rapid-prototyping system which Ray describes as "the CATIA of avionics". The system enables a designer to create a cockpit for a customer, using graphical objects which are stored in a library along with their "behaviour" - for example, an airspeed indicator, along with the parameters governing its operation, can be called up, customised and inserted into a display.
This way, a working display, or even a complete cockpit, can be created on a workstation, then downloaded into a simulator to be evaluated by the customer. Collins' Requirements Demonstration and Validation Facility allows new displays to be "flight-tested" in a fixed-based simulator. This can be connected to a detailed model of the target aircraft's autoflight system, produced by another Collins design tool, enabling a realistic human-factors evaluation of the design.
Design tools such as this are essential if the potential of LCDs to alleviate some of the human-factors concerns with cockpit automations is to be realised, Ray says. Already, Collins is using the VIVID to create innovative formats which will be made possible by even larger LCDs now available. Using new 350mm displays from Sharp, the company is experimenting with formats which combine primary-flight and multi-function displays on one screen.
Honeywell, similarly, is pursuing novel formats, including one called the flight-situation display. This incorporates the conventional primary-flight display, as well as radio-tuning information, and a new powerplant-parameter display called the engine monitoring and control system (EMACS). The NASA-developed EMACS has been tested against a conventional engine-indication and crew-alerting system (EICAS), and results showed a 100% failure-detection rate versus 57% for the EICAS.
Unlike an EICAS, which presents engine-related data in the form of an electronic instrument, the EMACS compares raw sensor data related to other parameters to determine the best value range for the conditions. Degraded performance can be detected and the crew alerted in an easily understood format, says Honeywell.
Other ideas which the company is pursuing include the PPA, a portable device for flight planning and data retrieval, which resembles a lap-top computer. The PPA will store and display electronic manuals, charts and maps, as well as uplink and downlink data and messages. Two such devices would be stored in docking stations in the aircraft, and synchronised when removed. The battery-powered PPA contains an Intel Pentium processor, hard disk, modem and infra-red link to a separate keyboard.
Honeywell, like Collins, is investigating various cursor-control devices, including joysticks, touchpads, light pens and trackballs. Final selections may depend on cockpit size, as well as manufacturer and operator preference, the company says. The use of cursor-controlled pull-down menus, Windows-based display pages and computer-generated soft keys on the displays are expected to reduce pilot workload.
A voice-command system is being developed for the Primus Epic. "It looks like the technology is getting there," says Lary Clark, manager of Honeywell's next-generation system. The company would like to see voice control used to call up checklists and approach plates and to set utilities such as cabin temperature.
One of the key voice-command interfaces would be with the aircraft utility-control system, which would be a centralised replacement for the numerous dedicated control-panels and electronic control-units associated with systems such as electrics, hydraulics and fuel. "This is the system we have looked at with the potential for most benefit," says Clark.
Between them, Collins and Honeywell are taking a long look forward at the potential for new technology to tackle some of the cockpit-management problems that the industry is only now beginning to acknowledge were created by the headlong rush to embrace CRTs and automation. This time, it seems, pilots will not be left out of the loop.
Source: Flight International
