ALL FUTURE DOUGLAS (DAC) aircraft will share a common display and avionics architecture to be based around Honeywell's Versatile Integrated Avionics concept, VIA 2000.

The MD-95 will be the first aircraft to be equipped with the full system, while the MD-90 is set to be changed to the VIA 2000 by around 2000. The 29 MD-90s bound for Saudia will form a hybrid intermediate step, as they will be fitted with only the display elements of the Honeywell system. The MD-XX widebody-tri-jet derivatives of the MD-11 now under study will, if the aircraft is launched, also feature the same basic cockpit architecture.

"We set a strategy of where we wanted to be on our flightdecks, but we could not afford to redesign everything every time, so we went back to the basic design and started from there," explains design and technology avionics and simulation general manager Joe Ornelas.

DAC's strategy was affected by outside influences, such as the rapid advances in manufacturing of flat-panel liquid-crystal displays (LCDs) and associated cost reductions. The development of modular avionics for the Boeing 777, as well as LCDs, also came at a good time for DAC as it struggled to launch the MD-95. By sheer serendipity, the VIA 2000 system and its advanced display technology therefore became available at the right time and at the right cost.

"Finally, we matched the strategic plan with the programme plan and ended up with the advanced flightdeck," says Ornelas. "We worked together with Boeing on some of this," adds MD-95 systems general manager Ken Peterson. "We did not want to compete on avionics piece parts, so the VIA 2000 box is identical to the one used in the 737 and the MD-90. Only one card is different. The level of commonality is astronomical between the 737, 777, MD-90 and MD-95 and the manufacturing base is broad. It's a very cost-effective solution," Peterson adds.

The baseline MD-95 operating system is derived from that of the MD-11, which Peterson believes has the most advanced flight controls and integrated displays in the industry - including those of the 777. He adds: "We believe it's a good baseline to go from, so why re-invent the wheel?"

The advanced flightdeck of the MD-95 will be dominated by six 200 x 200mm flat-panel displays. The line-up will include two primary flight displays, two navigation displays, a fifth for engine and alerts and a sixth is for systems.

Behind the scenes, dual VIA computers will integrate the flat-panel-display electronics and related software. They will also be used to perform the flight-management function, including providing provision for Future Air Navigation System requirements. Digital flight-data acquisition and the central aural-warning system will also be controlled by the two processors.

As well as supplying the VIA 2000, Honeywell will provide the MD-95 Category IIIa autoflight system (upgradable to Cat IIIb), including predictive windshear detection and stall warning. The company is also supplying the aircraft's central fault-display system.

In addition, DAC is removing the two MD-80/90-style multi-function-control display units (MCDUs) and replacing them with two MD-11-type MCDUs. "We've redesigned the pedestal completely," adds Ornelas. "We have modularised it and taken out some of the 1960s systems, like the mechanical-trim indicator and take-off-warning computer, allowing us to put in the larger MCDUs."

The Saudia MD-90s flightdecks will be built to a configuration known as Advanced Common Display. Eventually, all MD-90s will have the Advanced Flight Deck configuration, as will the MD-95, Ornelas explains, adding that " will offer shorter assembly times and improved reliability". The first MD-90 for Saudia will be completed by October 1997, while the target date for the first MD-95 is April 1998.

Source: Flight International