Modern commercial aviation is all about efficiency. Airlines and manufacturers alike look for opportunities to improve efficiency across all aspects of the business. One area where significant innovation has taken place in recent years is in engine design. Engine choice is a big decision for operators, and it directly affects fuel burn and operating costs. In many cases, one aircraft model can be powered by many engine models, adding complexity and nuance to the discussion.

Two of the largest engine manufacturers today are Pratt & Whitney and CFM International. Both companies compete in the single-aisle (narrowbody) airliner market, and even on the same aircraft at times. For those outside the aviation community, all engines probably blend together and simply represent the power source of an aircraft. In reality, engines are carefully refined by manufacturers and compared by operators to find the best fit. This article will profile both Pratt & Whitney (PW) and CFM and examine how each company’s engine designs and offerings differ.

Pratt & Whitney: A Brief History

Pratt & Whitney was founded in 1925 in the United States and is headquartered in East Hartford, CT. The company quickly became a cornerstone of the aviation industry. In its early years, the company built powerful and reliable piston engines that helped fuel the rapid growth of aviation. During World War II, Pratt & Whitney engines powered many military aircraft, establishing a reputation for engineering excellence, large-scale production, and dependability.

When aviation moved into the jet age, Pratt & Whitney transitioned to turbojet and turbofan technology. The company became a major supplier of engines for both commercial airliners and military aircraft, playing a key role in the expansion of long-haul air travel and modern air forces. This dual presence in civilian and defense markets allowed Pratt & Whitney to continuously invest in advanced materials, aerodynamics, and manufacturing processes.

Today, Pratt & Whitney is a subsidiary of RTX Corporation and has focused on improving engine efficiency, most notably through the development of the Geared Turbofan (GTF). By introducing a reduction gearbox between the fan and low-pressure turbine, the GTF represented a significant departure from traditional engine design. This innovation reflects Pratt & Whitney’s willingness to pursue transformative technologies and the greater emphasis on engine innovation in the aerospace industry.

CFM: A Brief History

CFM International was founded in 1974 as a 50/50 joint venture between the American company, GE Aerospace, and the French company, SNECMA, which is now Safran Aircraft Engines. The company is now headquartered in Cincinnati, OH. This transatlantic partnership was unusual at the time but proved strategically powerful, combining GE’s engine design expertise with Safran’s manufacturing capabilities and European market access. From the beginning, CFM was structured as a global supplier rather than a national champion, positioning it well for long-term commercial success.

The company’s first defining product was the CFM56 engine (pictured above). Although early sales were limited, the engine gained traction in the 1980s as airlines sought quieter and more fuel-efficient powerplants to meet stricter noise regulations and rising fuel costs. Boeing selected the engine for the Boeing 737 Classic and Next Generation families, which was a huge win for CFM. This, along with Airbus choosing the CFM56 for its original Airbus A320family, transformed CFM’s fortunes. Over time, the CFM56 earned a reputation for durability, ease of maintenance, and strong dispatch reliability, becoming the most-produced commercial jet engine family in history.

Source: CFM

More recently, CFM transitioned to the LEAP engine family as the successor to the CFM56. LEAP incorporated advanced materials and manufacturing techniques, including composite fan blades, ceramic matrix composites, and additive manufacturing, while maintaining a conventional engine architecture. Chosen as the sole engine for the Boeing 737 MAX and one of two options for the Airbus A320neoLEAP solidified CFM’s dominance in the narrowbody market and reinforced its reputation for evolutionary innovation and operational reliability.

Design Philosophies

Pratt & Whitney and CFM approach engine design from different philosophical starting points. Pratt & Whitney is most known for its Geared Turbofan (GTF) concept. This allows the fan and turbine to operate at their optimal speeds independently by inserting a reduction gearbox between the fan and the low-pressure spool. This prioritizes aerodynamic efficiency, lower fuel burn, and reduced noise, even if it introduces additional mechanical complexity.

On the other hand, CFM’s design philosophy places a strong emphasis on advanced materials, particularly composites, as a means of achieving efficiency without radically changing engine architecture. The LEAP engine was the first commercial turbofan to feature a full composite fan blade and fan case, produced using resin transfer molding. The turbine shrouds were made out of ceramic matrix composites (CMCs), which are able to withstand much higher temperatures than traditional metal components. These elements are also much lighter, contributing directly to improved fuel efficiency.

Source: Simple Flying

Each manufacturer has different points of focus on engine design. Pratt & Whitney focuses on new engine architecture, whereas today, CFM prioritizes innovating existing structures with modern technology, such as composites. In other words, Pratt & Whitney has a disruptive philosophy, and CFM has an evolutionary philosophy. The contrast between these approaches helps explain not only performance differences but also how airlines perceive, operate, and support engines from each manufacturer.

A320neo Engine Options

A good case study for comparing each manufacturer’s engines is the Airbus A320neo. This aircraft has the option to be fitted with either a Pratt & Whitney engine or a CFM engine. Developed from the original A320 family, the A320neo offers lower fuel burn, among other advantages for operators. In particular, Airbus advertises up to 20% lower fuel burn on the A320neo compared to its predecessor, mostly thanks to the two new engine options.

The two engines available on the A320neo are the CFM International LEAP-1A and Pratt & Whitney PW1100G-JM. Both engines contain advanced technology that makes the A320neo much more attractive than its predecessors. The PW1100G-JM is a variant made for the A320neo and features the aforementioned geared turbofan architecture. The LEAP-1A is a non-geared turbofan that uses composite materials, such as ceramics and carbon fiber, in its fan blades to make the engine lighter. The table below compares the two engines.

Source: CFM, Pratt & Whitney

The true engine option nature of the A320neo is a great benefit to airlines and operators. While both engines are solid choices, operators may prefer one manufacturer for any number of reasons. Much like how each engine offers different design philosophies, each airline will have a different operational philosophy to justify the selection of one or the other.

Airline Perspectives And Other Considerations

For Airlines, engine selection extends well beyond design philosophy and advertised performance. Reliability, maintenance costs, spare engine availability, and global support infrastructure all play critical roles in daily operations. Fleet commonality is another major factor. Unlike the A320neo, the Boeing 737 MAX is exclusively powered by the CFM LEAP-1B, eliminating engine choice entirely for airlines committed to flying the aircraft. This is a major consideration for airlines considering the 737 MAX family.

Noise is another important consideration, particularly for airlines operating at noise-sensitive airports or during night curfews. Both the PW1100G-JM and LEAP-1A offer significant noise reductions compared to previous-generation engines, but the geared turbofan’s slower-spinning fan gives Pratt & Whitney a measurable advantage in perceived noise levels. This can translate into greater operational flexibility and improved community relations, benefits that are difficult to quantify but increasingly valued by regulators and airport authorities.

Lastly, fuel consumption is the central driver of engine choice, as even small percentage differences can translate into substantial cost savings over the lifespan of an engine. The Pratt & Whitney GTF typically demonstrates slightly better fuel efficiency in ideal operating conditions, while the LEAP’s fuel burn is competitive and often favored for its consistency across varying mission profiles. However, Pratt & Whitney’s GTF engines have been plagued by persistent issues in recent years. In short, a manufacturing defect caused contaminated powdered metal in internal engine components. This has affected many airlines, and has even led Air Austral to retire its entire Airbus A220-300 fleet by Summer 2026, which is powered by the PW1500G. These issues are perhaps the greatest consideration for operators comparing the two engine manufacturers at the moment.

Future Outlook

The future of both these companies will certainly be interesting. On one hand, Pratt & Whitney has real manufacturing hurdles to work through with the issues on the GTF. For them, the future looks to be one of greater scrutiny and pressure from airlines to resolve issues. On the contrary, CFM is not facing problems like Pratt & Whitney. The most interesting future development for CFM is its RISE program, which was announced in June 2021. It features an open-rotor engine design and is slated to be the successor to the LEAP program. None has been formally introduced onto the market yet. Overall, both Pratt & Whitney and CFM represent decades of aircraft engine innovation and achievement. Together, they power thousands of narrowbody aircraft that fly all over the world every day.