Bombardier is planning to offer airlines a longer-range version of the CRJ700 regional jet as the result of a package of structure and subsystem changes in development for the stretch CRJ900 derivative being fed into design of the existing 70-seater aircraft.

"At the end of the CRJ900 development programme there are going to be some things we want to look at and make good on the CRJ700," says Jean-Guy Blondin, Bombardier CRJ700/900 programme director.

This includes the CRJ900's main wing which is being structurally reinforced with thicker gauge leading and trailing spars to support the 86-seat jet's higher baseline maximum take-off weight (MTOW) of 36,550kg (80,500lb).

The CRJ700ER currently has a certified MTOW of 34,040kg, but during development the aircraft's envelope was tested up to 34,960kg.

By making the CRJ900 wing standard on the CRJ700, production is not only simplified, but it will enable the jet to operate at the higher weight and extend by around 370km (200nm) its present maximum range of 3,670km.

"Some of our regional customers are asking for a bit better range capacity to operate from the US midwest to the east coast and from mideast to the west coast That's something we think we'll be able to do with a long range CRJ700. The CRJ900's wing, which is 27kg heavier, is the same size and geometrically identical to that of the 70-seat and both share the same fuel tank configuration," says Blondin.

Bombardier is looking at making a number of other changes to the CRJ700 to bring the aircraft operations in line with that of the 86-seat version.

These include the CRJ900's main landing gear wheels which have been strengthened for higher landing speeds and its Liebherr environmental control system, which has been redesigned around a ram air flow modulation valve for faster cabin temperature pull down time.

The larger derivative also features modified avionics software and an Engine Crew Alerting System to take into account the CRJ900's uprated General Electric CF34-8C5 engine and additional cabin service and luggage hold doors.

"This avionics software will also be introduced onto the CRJ700 with a pin connector to tell a CRJ700 from a CRJ900 and activate the appropriate messages or displays," says Blondin.

Source: Flight International