New Boeing Narrowbody Gets Engine Upgrade
Boeing’s ability to use the same engine for the 737-900ER as it uses on the standard -900 undoubtedly helped the company justify its investment in the proj

Boeing’s ability to use the same engine for the 737-900ER as it uses on the standard -900 undoubtedly helped the company justify its investment in the project, but that doesn’t mean the newest 737 won’t benefit from new powerplant technology. In fact, every 737-900ER will come with CFM56-7B engines equipped with CFM International’s so-called technology insertion upgrade, scheduled to make its appearance in service for the first time in early 2007.

Launched in September 2004 under the title CFM56 Tech Insertion, the program incorporates advances developed and validated as part of CFM’s wider Tech56 effort to lower maintenance costs, nitrogen oxide (NOx) emissions and fuel burn. It includes improvements to the high-pressure compressor, the combustor, and the high- and low-pressure turbines.

Using new analytic tools developed for the TAPS (twin-annular pre-swirl) combustor, CFM has improved the cooling and optimized the dilution in the current CFM56 single-annular combustor to cut NOx emissions beyond new International Civil Aviation Organization (ICAO) Committee of Aviation Environmental Protection CAEP/6 standards scheduled to take effect in 2008.

Changes in the turbine include a low-shock, high-pressure turbine blade contour that lowers the interaction loss between the high- and low-pressure turbines, helping to reduce fuel burn and improve durability. The design also includes a more durable low-pressure stage one turbine nozzle.

The first CFM 56 Tech Insertion will go in a 737-800 for testing in January 2006. CFM expects to incorporate the improvements in all new CFM56-7Bs and CFM56-5Bs in time for first 737-900ER deliveries to Lion Air in mid-2007. CFM also plans to offer upgrade kits by late 2007. More than 5,400 CFM56-5B and CFM56-7B engines operate in service on Airbus A320-family jets and Boeing 737s.