Boeing hopes to deliver a 2% improvement in fuel burn on its BBJ product line through a combination of aerodynamic improvements and engine technology changes, set to be rolled out in mid-2011.

The CFM56-7B Evolution engine, which accounts for roughly 1% of the improvement, will feature reshaped blades and vanes of the high- and low-pressure turbines to increase airflow through the engine and reduce overall temperature.

Boeing and CFM will introduce changes to the engine nozzle and plug, and remove about 9% of engine aerofoils from the high- and low-pressure turbines, to reduce maintenance costs by up to 4%.

Aerodynamic changes to the aircraft include a reshaped anti-collision light, refined wing control surfaces, revised main landing-gear wheel-well fairing and a modulation of the environmental control system inlet and exhaust.

The airframer first announced the package of changes for its commercial line in late April.

Boeing and CFM tailored these changes at operators flying BBJ routes greater than 1,850km (1,000nm).

"The longer you're in cruise, the more fuel burn improvement you're going to get," says 737 chief project engineer John Hamilton at Boeing announcement last month.

Source: Flight Daily News