The LEAP's basic architecture includes a scaled-down version of Safran's low-pressure turbine used on the GEnx engine.

[6] Compared to the CFM56, the LEAP makes greater use of composite materials, has a second-generation Twin Annular Pre-mixing Swirler (TAPS II) combustor, and a bypass ratio around 10–11:1.

[9][10] Reliability is also supported by use of an eductor-based oil cooling system similar to that of the GEnx, featuring coolers mounted on the inner lining of the fan duct.

According to Aviation Week's article, "The eductor device produces a venturi effect, which ensures a positive pressure to keep oil in the lower internal sump.

[1][17] The first engine entering the test program reached and sustained 33,000 lbf (150 kN) of thrust, required to satisfy the highest rating for the Airbus A321neo.

[6] CFM carried out the first test flight of a LEAP-1C in Victorville, California, with the engine mounted on the company's Boeing 747 flying testbed aircraft on 6 October 2014.

The -1C version features a thrust reverser equipped with a one-piece O-ring replacing a two-piece door.

The thrust reverser is deployed by the O-ring sliding aft, reducing the drag that was induced by the older design and improving efficiency.

[3] Also, on the A320neo, where the engine competes head-to-head with the Pratt & Whitney PW1000G, the LEAP had captured a 59% market share in July 2018.

[2] With the 737 MAX introduction, CFM delivered 257 LEAPs in the first three quarters of 2017, including 110 in the third: 49 to Airbus and 61 to Boeing, and targets 450 in the year.

[34] To cope with the demand, CFM is duplicating supply sources on 80% of parts and even subdivide assembly sites, already shared between GE and Safran.

[35] GE assembles its production in Lafayette, Indiana, US in addition to its previous Durham, North Carolina, US facility.

[35] Pratt & Whitney acknowledges a production ramp-up bottleneck on its rival PW1100G geared turbofan including a critical shortage of the unique aluminium-titanium fan blade, hitting the Airbus A320neo and the Bombardier CSeries deliveries.

[37] In mid-June 2018, deliveries remained four to five weeks behind schedule, down from six, and should catch up in the fourth quarter as the quality variation of castings and forgings improves.

[3] The production has no single manufacturing choke point by selecting multiple suppliers for every critical part.

Safran discovered a production quality defect on LEAP-1B low-pressure turbine disks during assembly for possibly 30 engines, and CFM is working to minimize flight-test and customer-delivery disruptions.