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LEAP-1B engine for single-aisle commercial jets


LEAP-1B, a new-generation engine for the B737 MAX


LEAP-1B engine for single-aisle commercial jets

Safran Aircraft Engines

Max. takeoff thrust (lbf) 28,000

Fan diameter (in) 69

Entry into service 2017

Designed, produced and marketed by CFM International, the LEAP-1B is the exclusive powerplant for Boeing’s new-generation 737 MAX single-aisle jet.

LEAP-1B engine for single-aisle commercial jets

Safran Aircraft Engines

Max. takeoff thrust (lbf) 28,000

Fan diameter (in) 69

Entry into service 2017

15% reduction in fuel consumption and CO2 emissions*

*Compared to previous-generation engines.

Up to 50% reduction in NOx emissions*

*In accordance with the ICAO’s CAEP/6 environmental standard.

Meets the most stringent noise standards (ICAO’s Chapter 14)

Key figures
10,000 +
orders for LEAP engines (in backlog)
160 +
LEAP operators worldwide
35 +
million flight hours
Boeing 737 MAX

An environmentally-friendly engine

Designed to meet the challenge of decarbonizing air transport, the LEAP-1B engine offers Boeing 737 MAX operators enhanced performance in terms of fuel consumption and CO2 emissions (15% lower1), NOx emissions (up to 50% lower2) and noise (in accordance with Chapter 14).

1. Compared to previous-generation engines.

2. In accordance with the ICAO’s CAEP/6 environmental standard.

State-of-the-art technologies

The LEAP-1B engine benefits from the latest innovations in materials and production processes.

Discover the LEAP -1B engine

LEAP-1B engine : 00 minute and 28 seconds
Carbon fiber weaving loom in 3D

Innovation from nose to tail

To achieve its remarkable performance, the LEAP-1B is packed with innovative technologies and materials. The use of a 3D woven composite material and the RTM (resin transfer molding) process developed and patented by Safran Aircraft Engines makes it possible to produce fan blades that are lighter, stronger and more durable. The low-pressure turbine blades are machined from an innovative titanium-aluminide alloy that is lighter and more resistant to high temperatures. The low-pressure turbine rings and airfoils are made of CMC (ceramic matrix composite) materials and the fuel injectors are 3D printed.

Pulse line dedicated to final assembly of LEAP engines

High-performance industrial organization

Thanks to Factory 4.0 facilities and unique processes, Safran Aircraft Engines has achieved a production ramp-up that is unprecedented in commercial aviation history. The LEAP engine final assembly line in Villaroche, near Paris, has earned the “Showcase for the Industry of the Future” label in France.

A high-performance supply chain

The LEAP-1B production system is anchored in a multi-source approach, involving a global network of suppliers with the capacity to sustain the high delivery rates.

Storage area

Proactive suppliers

With the LEAP-1B engine’s success, Safran Aircraft Engines has set up a powerful logistics organization to meet strong customer demand. Its supply chain calls on more than 150 direct suppliers in 14 countries. Building on a long-term partnership approach, Safran Aircraft Engines helps suppliers continuously improve their operational performance in terms of quality, costs and lead times. This organization has largely contributed to the success of the production ramp-up.

A successful partnership

Like its predecessor, the CFM56, the LEAP-1B engine was developed and is produced by CFM International, the successful partnership between Safran Aircraft Engines and GE.

LEAP engine mock-up

Half a century of cooperation

Established in 1974, CFM International is a 50/50 joint company between Safran Aircraft Engines and GE. This partnership, now extended to 2050, has spawned the best-selling engine in commercial aviation history, the CFM56, and its successor, the LEAP. Today, CFM International is the global market leader in engines for mainline commercial jets (over 100 seats). Safran Aircraft Engines and GE are equal partners in the design, development, production, sale and support of all versions of the LEAP. Final assembly is performed at both GE facilities in the United States and Safran Aircraft Engines facilities in France.


Safran Aircraft Engines offers a complete package of support services for the LEAP-1B

Customer Support Center - Montereau

Proximity and flexibility

Through CFM Services, Safran Aircraft Engines provides LEAP-1B customers with a wide range of services tailored to each one’s business model and evolving fleet size, including time & material contracts, support-by-the-hour contracts and customized support solutions. These services are delivered through a dozen MRO centers worldwide, which together employ over 3,000 people, more than half of them based internationally in close proximity to operators. This gives operators a high degree of fleet management flexibility and greater control over their long-term maintenance expenses.

  • © Safran
  • © Antonio Gomez / Safran
  • © Philippe Stroppa / Safran
  • © Raphael Olivier / CAPA Pictures / Safran
  • © Christel Sasso / CAPA Pictures / Safran
  • © Adrien Daste / Safran