PAUL LEWIS / MIRABEL
Bombardier eyes upgrades to improve production lead times and aircraft performance
Bombardier has decided to standardise on the CRJ900 wing forthe smaller CRJ700 regional jet in a move to inject a higher degree of production commonality and reduce lead time on the aircraft. The company is conducting several other trade studies to feed back into the 70-seater any changes made designing the 86-seat stretch version.
The differences between the two wing specifications are confined to thicker gauge skins, spars and wing planks, as well as material changes to the wing-fuselage attachments on the CRJ900, which adds up to an additional 30kg (66lb) in weight. A common wing will be introduced from the 120th aircraft onwards, with numbers 109 and 110 now in the final stages of assembly.
Simplifying wing production will reduce the time airlines have to decide between the CRJ700 and CRJ900 version from 18 months to 15 and Bombardier hopes to cut this time further to just 12 months. "In the future, having a more capable wing could allow us to open up zero fuel weight increases or maximum landing weights," says Jean Guy Blondin, Bombardier CRJ700/900 programme director.
Bombardier plans to raise the CRJ700's maximum take-off weight (MTOW) from the current 34,050kg (75,000lb) to 34,960kg, with static and fatigue testing already completed. If combined with the CRJ900 wing, the MTOW could be further raised to 36,320kg and range extended another 200km (110nm) out to 4,440km.
"We know we can do it, but there hasn't been much market interest so we're sitting on it, "says Blondin.
Other areas of commonality being looked at include the Mitsubishi-built aft fuselage, which on the CRJ900 has structural strengthening for a sturdier tail bumper and two ventral fins. Another option is to adopt a standard CRJ900 structure, but make the mounts removable for the CRJ700.
Also being considered is equipping the CRJ700 with the stretch version's sturdier BF Goodrich main landing gear.
Another option studied prior to September 2001, fitting the CRJ900's 5% more powerful General Electric CF34-8C5 engine on the CRJ700 and shortening its take-off run by 76m (250ft), is not under discussion.
Source: Flight International
