Thales study of fly-by-wire may appeal to Bombardier
Thales Avionics Canada has directed its engineering staff to accelerate design work on a fly-by-wire (FBW) flight-control system, enhanced vision system (EVS) and required navigation performance (RNP) avionics for business jets and regional airliners. Most likely to benefit from the bulk of the designers’ early work will be Bombardier, a neighbor of Thales in Montreal and the world’s third-biggest airframe manufacturer.
Thales’ engineering team, based near Montreal Dorval Airport, will be immersed in the projects for the better part of the next three years–just enough time, say senior Thales executives, for the aerospace industry to recover from its latest production down cycle.
Funding for the initiatives comes from a Technology Partnership Canada (TPC) research grant totaling $6.25 million (C$9.9 million), and an additional $14.25 million from Thales’ own pocket. Jean-Pierre Morteux, president and CEO of Thales Avionics Canada, and Allan Rock, Canada’s interior minister, in November announced the government award during a press conference at Thales’ Montreal headquarters. At the time, Morteux pronounced the TPC investment would help Thales “further innovate and maintain our leading edge in avionics and flight controls” for business and regional aircraft. In an interview after the press briefing, Morteux offered some less obvious benefits of the technology projects.
The research grant, he explained, gives the Montreal design center the chance to develop new technology while at the same time avoiding workforce reductions. Although business is down, the company actually plans to add six to nine engineers for the EVS program, bringing the total number of Thales employees in Montreal to more than 130. Morteux said he now anticipates U.S. and European economies will not fully recover from their slumps until 2005, but added he is hopeful the company can maintain the current staffing level.
Bombardier’s Close Ties
“This technology initiative helps us prepare for the recovery that we see coming perhaps not as quickly as some others,” he said. By exploring new technologies such as FBW, which is planned for integration in the next generation of business jets in the latter half of this decade, Thales’ engineering staff keeps busy and the company is better positioned for the next up cycle, he said.
The total TPC funding allocated for the trio of initiatives is broken out so that roughly 40 percent is applied to EVS research, 40 percent to the fly-by-wire program and the remaining 20 percent to RNP. TPC is a government-operated investor in Canadian companies, founded to help spur growth at Canadian high-tech firms, especially at small to midsize companies.
Illustrative of the close ties Thales has to Bombardier is the fact that it already serves as the main supplier of conventional flight controls in Bombardier’s CRJ700, CRJ900 and Global Express, and is the lead integrator of EVS in the Global Express, alongside sensor maker CMC Electronics, also based in Montreal.
Flight tests of the EVS for the Global Express are scheduled to begin in April from Wichita Mid-Continent Airport and will be followed by a comprehensive design review next December. Priced at about $500,000 (not including installation) the system is placed to compete with the Kollsman EVS certified in the Gulfstream 550. Customer availability of the Thales/CMC system is expected in the first quarter of 2005. Texas Instruments’ flight department is the launch customer.
Known as the Bombardier enhanced vision system (BEVS), the sensor package will be offered as standard equipment in all new Global Express production airplanes starting in 2005 and will be available for retrofit through Bombardier’s service network.
As described, the BEVS will integrate the Global Express’ Thales-built head-up display with a CMC SureSight forward-looking infrared sensor mounted in the nose just below the windshield. More pilot controls will be added to the existing HUD control panel and the image will be transmitted to an existing multifunction display or FMS, allowing the copilot to see the pilot’s view through the HUD.
Exploring the FBW Envelope
Thales Avionics Canada has been developing flight-control systems since the unit was founded in 1997. The shift of focus from conventional flight controls to FBW, which has already started in earnest on the company’s drawing boards and Catia screens, illustrates the recent acceptance of the concept. Dassault has announced that its new Falcon 7X will incorporate FBW, while other manufacturers are understood to be exploring FBW for their next-generation business jets.
Reduced crew workload, better aircraft performance and increased safety are cited as the major benefits of FBW. In Thales’ case, the FBW design philosophy should be quite similar to that found on Airbuses, the prototype for all civil FBW concepts. Side-stick controls, however, are not mandatory–that decision will be left to the airframe manufacturer.
Although Thales offered few specifics, its FBW system at a minimum should include flight-envelope limitations for angle-of-attack/attitude, load factor and speed. Through its onboard computers, the aircraft will be protected against sustained flight above Mmo, for instance.
And although the pilot could not deliberately overshoot the FBW system’s attitude limitation, the aircraft could. In the case of strong turbulence, for example, the airplane might be forced into a dangerous attitude, at which time the FBW controls would automatically perform the recovery.
As for Thales’ RNP initiative, the company is preparing for the debut of flight evaluations with Horizon Air, sister airline of Alaska Airlines and an operator of Bombardier RJs and turboprops. Alaska Airlines already operates RNP approaches and routes, including one instrument procedure to Juneau, Alaska, that curves through the Gastineau Channel mountain pass.
RNP defines the ability of an aircraft’s navigation equipment to achieve a specified level of lateral accuracy 95 percent of the time. For example, RNP-10–typical for oceanic operations–should keep the aircraft within ±10 nm of its required track nearly all the time. But RNP can go to as low as ±0.02 nm, or ±35 meters, typical of the accuracy required for ILS, MLS, LAAS and the future WAAS-based approaches. With a certified RNP capability, more airspace “tunnels” can be safely accommodated, with significant capacity increases.
The tighter RNP requirements are, the more demanding the onboard avionics systems certification. For example, the integrated IRS/GPS/FMS/autopilot/EGPWS avionics package required to achieve RNP-0.11 in Alaska Airlines’ Boeing 737s is hugely expensive compared with that required for basic RNP-10.