As the CFM56 engine program recently marked its 30,000th engine delivery, here are some key facts about the most popular commercial aircraft engine that's really "grown up" over the past five decades.

•    CFM56-7B demonstrates high performance and reliability with an industry leading 99.96 percent engine dispatch reliability rate, which equates to only one delay or cancellation every 2,500 departures.  

•    The CFM56 engine can stay on wing for as many as 20,000 cycles, with an average time on wing (TOW) of 18,000 cycles to its first overhaul; that's approximately nine years without removing the engine for heavy maintenance [see time to first shop visit chart below; TOW data accumulated from CFM's Fleet Data Management (FDM) system].  

•    CFM56-7B has experienced more than 1,000 design improvements since the engine's entry into service to improve reliability, durability and operating costs. TOW has doubled over the past 10 years, and CFM expects it to continue to improve as engines with the Tech Insertion upgrade and CFM56-7B Enhanced upgrade reach their potential in the coming years.