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Regional revolution

In just two years, the line-up of players in the emerging 70-110-seat regional jet market has been transformed

PAUL LEWIS / MONTREAL, MUNICH AND SAO JOSE DOS CAMPOS

In the mere two years since the last Paris air show, the line-up of players in the emerging 70 to 110-seat regional jet (RJ) market has changed considerably. The Bombardier BRJ-X has been quietly dropped in favour of a further stretch of the successful CRJ line. Fairchild Dornier was rescued from the financial brink and its 728/928JET programme revived by an overdue injection of new capital but at the expense of the smaller 428JET. Embraer, fortified by a New York listing and a French strategic investment tie-up, added a third member to its ERJ-170/190 family and has a possible fourth warming up in the wings.

Aircraft may have changed shape, increased in weight and slipped development schedules, but rapid growth in the regional air transport market has stayed constant and continues to outstrip mainline flying. As load factors steadily rise, so do runway congestion and pilot pay claims - which manufacturers believe will in their turn fuel demand for larger, more economical aircraft. Industry forecasts suggest an emerging market for 4,000 or more jets of 60 to 110-seat size over the next 20 years.

What this means for aircraft design is open to different interpretations. Bombardier views the market as an extension of the existing regional niche and, accordingly, has elected to keep within the confines of its tried and tested CRJ line. In sharp contrast, Embraer and Fairchild Dornier have opted for larger, clean sheet designs that offer no commonality with smaller regional jet types. They are instead forging a new market, crossing over from regional to mainline airline flying - traditionally the preserve of Airbus and Boeing.

Bombardier's initial inclination had been to break new ground with the proposed 90 to 110-seat BRJ-X until its clientele pointed it in another direction. "It's basically through these discussions that our current customers were asking us: why don't we make a 90-seater that is common to what we already have now? We kept telling them that we couldn't do that, but eventually, with a bit more encouragement, we found that we could," recalls Jean-Guy Blondin, CRJ700/900 programme director.

A large investment had already been made in growing the CRJ700 out of the CRJ200. By comparison, the CRJ900 represents a relatively simple and inexpensive 3.86m (12.7ft) stretch of the 70-seater. The first prototype is, in fact, a CRJ700 test aircraft with fuselage plugs fore and aft. The CRJ900 and 700 share 92% commonality compared with less than 20% with the 50-seater. The prospect of a common pilot rating, or at most minimal differences training, along with simplified spares support, is proving to be a big hit with existing operators, like launch customers Mesa and Brit Air who want to expand their fleets.

The derivative approach is a compromise over a BRJ-X-type clean sheet design. Bombardier tailored the CRJ700 for the 70/78-seat market at the airlines' behest, but with hindsight admits it would have designed a slightly larger wing if it had seen the need for a full size 90-seater. The CRJ900 can accommodate up to 86 seats at 31in (790mm) pitch, but going to 90 seats means sacrificing use of the aft service door and losing 0.6m³ of aft luggage hold space. It retains the same basic fuselage cross section dating back to the Challenger business jet, which limits seating to four abreast or three in business class.

Like earlier CRJs, the 900 uses conventional cable and servo flight controls and a six-tube Rockwell Collins Pro Line 4 electronic flight instrumentation system. The company has flown a fly-by-wire (FBW) Challenger demonstrator, but claims that 85% of airline respondents wanted to stick with conventional controls. Modernising the cockpit with liquid crystal displays had been another consideration, but one that would have dictated a major avionics redesign and, with carriers already stocked up with cathode ray tubes, it was not heavily endorsed.

"There is a trade-off between having new technology which is light, energy saving and produces less heat, and losing commonality. When we talked to the operators, commonality was the driving factor," says Blondin. "The CRJ900 is very much a traditional aircraft in terms of design and frankly our operators like that because they're really familiar with the technology. The regional industry doesn't have the technological resources of mainline carriers. The last thing they want is something brand new that nobody knows."

Fairchild Dornier and Embraer executives would beg to differ with their Canadian counterparts. While Bombardier seeks to leverage off an installed user base of more than 1,000 CRJs in service or on order, its Brazilian and American/German competitors are breaking with the smaller end of the regional jet market. Both the ERJ-170/190 and 728/928JET families are being designed from the outset with levels of cabin comfort and systems sophistication more akin to today's mainline aircraft than traditional regional operations.

"We believe the market will become more and more seamless with that of the mainline airline market," says John Wolf, Fairchild Dornier's chief operating officer.

New philosophy

"It was an opportunity and our responsibility when putting together an aircraft to design it for seamless service as opposed to a next generation regional jet that grew up from a smaller parent. This philosophy is the fundamental difference in how we approached this development."

The ERJ-170 and 728JET are noticeably heavier than the the CRJ700 and, in fact, are only marginally lighter than the CRJ900, which implies higher operating costs. The scales, however, quickly begin tilting in favour of the Embraer and Fairchild Dornier jets as airlines demand more seats, larger business-class sections and increased cabin amenities. This is understood to be a strong consideration in British Airways' and Qantas' joint requirement for up to 60 new 70 to 110-seat regional aircraft.

Both manufacturers are developing larger follow-on members for delivery in 2004-05. Embraer has unveiled two growth variants of the baseline 70-seater: the 6.33m stretch, 98-seat ERJ-190-100 and the 8.75m longer 110-seat -200. Also under study is an 86-seat ERJ-170-200 competitor to the CRJ900. The 928JET will seat up to 110 passengers in a slightly tighter economy-class seat pitch. Fairchild Dornier is debating a further 120-seat X28JET stretch or a shrunk 55-seat 528JET as its next complementary development.

The major discriminator between the two designs is in the fuselage cross-section. Fairchild Dornier has opted for a wider five-abreast cabin and Embraer a longer four-abreast fuselage. The 728/928JET has the ergonomic edge of offering a four-abreast business cabin and both versions are short enough not to need overwing emergency exits. However, the advantage of the ERJ-170/190 cabin is that no passenger is more than one seat from the aisle.

A key parameter for the ERJ-170 is the shortfield performance demanded by launch customer Crossair in order for the jet to operate from restricted airports such as London City and Lugano, Switzerland. Embraer had set a target of a 1,224m take-off field length with a standard load and fuel for 1,110km (600nm). The aircraft will incorporate double-slotted flaps with four settings and a choice of General Electric CF34-8 engine ratings from 12,800lb thrust (-8E2) up to 14,200lb thrust (-8E5A1) for hot/high conditions.

"We've had better than expected results from recent wind tunnel tests, and we will be updating with better figures," explains Luis Affonso, Embraer ERJ-170/190 programme director. "Our performance comes from having the moveable double-slotted flaps. One other feature we may have is a steep approach kit. For approach angles of 5í we can add a speed brake under the centre belly fairing to create drag," he adds.

Embraer and Fairchild Dornier are taking full advantage of their new designs to incorporate new technology. Both jets will feature an FBW system and Honeywell Primus Epic-based glass cockpit for primary flight, navigation/weather and the engine indication and crew alerting system display. Fairchild Dornier, at launch customer Lufthansa's urging, has added a sixth x25.4mm liquid crystal display for extra redundancy and cursor control devices. "We've integrated a good amount of the switching to take workload out of the cockpit. From a maintenance standpoint, we also think it's cheaper and easier to support," says Duncan Koerbel, Fairchild Dornier vice president 728/928JET.

Team tactics

Larger and more demanding new regional jets have required each manufacturer to forge wide ranging and, in some instances, overlapping partnership arrangements with structural and system suppliers in order to compress development schedules, rationalise resources and mitigate financial risk. All three programmes have involved partners from the outset in joint definition phases (JDP). In the case of the CRJ900, Bombardier convened the first JDP meeting nine months prior to the formal September 2000 launch, giving the programme a critical head start.

Timing was crucial in Bombardier's decision to take the derivative route. Even if the BRJ-X had been launched last year, it would have struggled to reach the market earlier than 2004, and before either the 928JET or ERJ-190. The CRJ900, on the other hand, is already four months into flight testing. The first production aircraft is scheduled to be delivered to Mesa in early 2003, more than a year ahead of its nearest 90-seat competitor and six months in front of the 728JET.

Delegated design

The CRJ700 was the first programme on which Bombardier delegated partial design authority to its partners and this teaming is essentially being replicated for the CRJ900. "We just can't sustain these programmes on our own without getting help technically and commercially from our partners. The amount of effort and money required to develop products like this is just overwhelming," explains Blondin.

Mitsubishi Heavy Industries is supplying the aft fuselage and Bombardier's Belfast plant the centre fuselage, including the two forward and aft extensions. GKN Westland is supplying the tailcone and Bombardier's Montreal production facility will retain the wing and cockpit, as well as final assembly. The only real change has been the switch from Avcorp to Gamesa for the vertical and horizontal stabiliser to keep pace with increased CRJ output.

GE has uprated the CRJ700's CF34-8C1 to the 14,535lb-thrust -8C5 with modified compressor bore cooling and improved turbine blade cooling delivery, higher temperature turbine vane material and a longer life high-pressure turbine rotor. Goodrich is equipping the 86-seat jet with a modified main landing gear with beefed up brakes and shock struts to handle the extra weight and higher landing speeds. Liebherr Aerospace Toulouse has modified the environmental control system with a new ram air flow modulation valve for faster cabin cooling.

Embraer has recruited a team of 16 partners for the ERJ-170/190, without which the programme would simply not have got off the ground in the time it did. Approximately half of the 600-man JDP team comprised partners/suppliers, which was critical, given that Embraer acknowledges it is 700-800 engineers short. "This created a deeper involvement and gave the partners a sense of property and ownership. The result is better, and requires less of our staff to define an aircraft that is larger and more complex than the ERJ-145," says Satoshi Yokota, Embraer vice president industrial.

Joint ventures

The Brazilian manufacturer has sought to cap foreign content at 50% for commercial and political considerations - a tall order given that Latecoere, Korean Air and Sonaca have contributed the centre fuselage sections, Gamesa the empennage and Kawasaki part of the wing leading and trailing edges. The answer has been the establishment of joint ventures, like ELED between Embraer and Liebherr, to locally produce the ERJ-170/190's nose gear. Other partners are being encouraged to complete their subassemblies in Brazil.

Fairchild Dornier has a different challenge. It is trying to produce a competitively-priced aircraft in Germany's high cost environment. The result is an aircraft in which 80% of its value is accounted for by partners and suppliers. "Can we be cost effective building an aircraft in Germany?" asks Wolf. "The answer is yes, if in designing and manufacturing an aircraft we bring to final assembly those major elements that require the least amount of labour."

The result is a 728JET wing and horizontal/vertical stabilisers built and pre-stuffed by EADS Casa, wingbox from Ogma, nose from Sabca, skins from Sonaca and frames from Israel Aircraft Industries. Honeywell has overall responsibility for the aircraft's avionics and GE the aircraft's powerplant, with Hurel Hispano supplying the nacelle and reverser and Aermacchi the inlet for the 728JET's CF34-8D. For the 928JETS' larger diameter CF34-10D engine, Good-rich will supply the entire package.

Industrial investment

Involving overseas partners has made the use of CATIA 3D digital design tools indispensable. Fairchild has constructed a digital mock-up to visualise design changes and parts interaction. Embraer went a step further and added an ERJ-170/190 virtual reality centre as part of a $80 million outlay on information technology over the last two years. "Virtual prototyping is essential now. You can't waste time and money building physical mock-ups. The biggest power is making things visible in 3D to a team of people who are designing and discussing solutions and to look at solutions as if they were on a physical mock-up," says Yokota.

Digital design has in turn opened the door to digitised manufacturing, including factory floor layout and 3D simulation of assembly actions to validate processes and the man/machine interface. Bombardier, Embraer and Fairchild Dornier are each constructing new, purpose-designed assembly buildings for the new aircraft, but are employing different methods to optimise output and ensure maximum flexibility when switching between versions. The centrepiece of Embraer's operation will be a new 16,000m2 hangar housing seven assembly docks.

Embraer plans to initially build up to five ERJ-170/190s per month, but wants the margin for growth, having ramped-up ERJ-135/140/145 output from four to 20 aircraft a month in only a few years and within a plant originally designed to build 19-seat EMB-110 Bandeirantes. Yokota explains: "The dock system is very adaptive in terms of rate. Production can be increased without changes in process."

Bombardier's new CRJ700/900 plant at Mirabel will employ a moving line, while Fairchild Dornier has opted for a similar approach for final assembly and a dock for customisation. Besides two new assembly and customisation buildings, the company has invested DM67 million ($30 million) in outfitting a former Second World War hangar with the latest manufacturing technology for fuselage barrel subassemblies. The emphasis has been placed on flexible tooling, such as the new Brotje automated gantry riveter, capable of handling 728JET and 928JET structures.

"The line gives us a drum beat and schedule to work to," says Ray Edwards, Fairchild senior vice-president production. "The components and feeds are the same for the basic aircraft, be it the 528, 728, 928 or X28JET. The biggest part in the variable comes with customisation, and with the dock we have got the flexibility to do different lead times and vary the input and output." The company's Oberpfaffenhofen plant will initially produce up to 60 aircraft a year, but has the capacity to go to 120.

The focus of all three plants is now on final assembly/first flight of their respective aircraft. The first production-configured CRJ900, as opposed to a plugged CRJ700, is scheduled to fly shortly followed by a second aircraft early next year. Final assembly of the first of six ERJ-170s will start in August ahead of a targeted maiden flight at the end of the year. Assembly of the first of four 728JET prototypes begins in September with the centre fuselage and wingbox mate and the first flight in March will complete the troika of new regional jets.

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