What type of engines do many new Boeing aircraft utilize for improved efficiency?

Many new Boeing aircraft utilize turbofan engines to improve fuel efficiency and overall performance. Turbofan engines are designed to provide a high bypass ratio, which means that a significant portion of the thrust is generated by the fans at the front of the engine through a large volume of air, rather than by the combustion of fuel in the core of the engine. This design not only enhances fuel efficiency, particularly at subsonic speeds where most commercial aircraft operate, but also reduces noise levels significantly, making them more environmentally friendly and compliant with stringent noise regulations.

In contrast, piston engines, turbojet engines, and rocket engines do not offer the same level of efficiency and are used in very different applications. Piston engines are typically found in smaller general aviation aircraft and are not suitable for the requirements of commercial air travel. Turbojet engines, while once popular in earlier jet airliners, have largely been replaced by turbofans for modern commercial aviation due to their lower efficiency and higher noise levels at subsonic speeds. Rocket engines, on the other hand, are primarily used for space exploration and have no application in commercial aviation. Thus, the turbofan engine is the optimal choice for modern Boeing aircraft, aligning with the industry's goals for better efficiency and sustainability.