The CFM56 is possibly the most flexible mid-size turbofan engine commercial aviation currently available. The CFM56 can be found on both the A320 family and the 737 Classic and NG families. It has also been used on the DC-8, KC-135 (707) tanker, and on the A340-200 and -300. The following tables illustrate the variations of the CFM-56 and its evolution over the years, showing the inventory of active aircraft at the end of the first quarter 2013.
The data show the number of in-service aircraft – so to compute the engine population, multiply by 2 or 4 appropriately based on aircraft type. Boeing has 33 variations of the CFM56 engine on 737 models while Airbus has 23 variants on A320 and A340 models, with several version, after continuing improvements, being used for each aircraft type. Although CFM is essentially a one engine company (until LEAP starts flying), it shares technology from its joint venture partners, SNECMA and GE.
CFM has had a great run with the CFM56. It will be hard to replace a program that has flown on more than 9,200 aircraft. The LEAP is off to a good start, with 801 of the 1,580 A320neo family that have seen engine selections (812 remain undecided) and 1,567 Boeing 737MAX. If a similar record can be shown 30 years from now, CFM will be very happy.