The CFM International LEAP (Leading Edge Aviation Propulsion) engines are high-bypass ratio turbofan engines that power the Boeing 737 MAX family of aircraft. The -1B model of the engine has a thrust range of 23,000 - 28,000 Ibf (100-120 kN), with a maximum takeoff thrust of 29,320 If (130 kN).

Excellent question. The thrust of the Boeing 737 MAX engine varies depending on the specific engine model and variant of the aircraft, but the key figures are in the 27,000 to 29,000 lbf range.

Here’s a detailed breakdown:

Primary Engine Options & Thrust Ratings

The 737 MAX is offered with two engine choices, both from the latest generation of high-bypass turbofans:

1. CFM International LEAP-1B: This is the sole engine currently certified and installed on all delivered 737 MAX aircraft. Boeing selected it as the exclusive provider.

   • Maximum Thrust: Approximately 27,000 to 29,000 pounds of force (lbf).
   • The exact rating depends on the 737 MAX variant and is software-limited by the Engine Control Unit (ECU). For example, the MAX 8 might use a lower thrust setting than the physically identical engine on a MAX 10, which is heavier and requires more thrust for takeoff.

2. Pratt & Whitney PW1100G (GTF): This engine was offered as an option during the initial sales campaign but was never developed or certified for the 737 MAX. All flying 737 MAX aircraft use the LEAP-1B.

Thrust by 737 MAX Variant

Here are the typical maximum certified thrust ratings for the main variants:

• 737 MAX 7: ~ 27,000 lbf
• 737 MAX 8: ~ 27,000 - 28,000 lbf
• 737 MAX 9: ~ 28,000 lbf
• 737 MAX