History of the CFM56-7B Turbofan Engine

The CFM56-7B engine is carrying on CFM’s tradition of providing customers with state-of-the-art engines that enable them to remain competitive in the tough international market.

The CFM56-7B was originally developed to provide Next-Generation 737 operators with higher thrust, improved efficiency, and lower maintenance costs than its predecessor, the CFM56-3. Since entering service in 1994, the CFM56-7B is delivering on that promise while providing industry-leading reliability. The engine has been able to achieve outstanding rates in very demanding circumstances. For example, Southwest Airlines 737s have one of the highest utilization rates of the fleet and typically accumulate 6 or 7 flights each day. This reliability made the CFM56-7B-powered 737 the first aircraft in its class to be granted 180-minute Extended-Range, Twin-Engine Operations (ETOPS) approval by the U.S. Federal Aviation Administration. ETOPS is defined as the number of minutes flying time from a suitable airport that a twin-engine aircraft may operate in the event that one engine becomes inoperable. The approval gives operating airlines far greater route-scheduling flexibility. 

In 2007, CFM breathed new life into the CFM56-7B fleet by introducing the Tech Insertion production standard. Compared to the base CFM56-7B, this new configuration provides operators up to 1 percent better specific fuel consumption over the engine’s lifecycle, and between 5 and 15 percent lower maintenance costs (depending on the thrust rating) through enhanced durability. The engine also meets current International Civil Aviation Organization (ICAO) CAEP/6 environmental standards.