The majority of a plane’s external components are more than just for visual appeal. They each serve a purpose. The winglets and flat-bottom engines, for instance, each have a specific function. Take the saw-toothed edges on the engines of the Boeing 787, the 737 MAX, and the 747-8. These distinctive edges, particularly noticeable on the engines of the 787 and 737 MAX, and the 747-8, are known as chevrons. They aren’t just for show; they were deliberately designed to fulfill a key function: minimizing engine noise.
Uncovering the Chevron Mystery
There’s an intriguing detail on Boeing 747-8, 787, and 737 MAX planes that often catches the attention of the untrained eye. These aircraft feature a unique design on their engines – the chevrons. These saw-tooth patterns aren’t just there for visual appeal; they serve a significant purpose related to engine noise reduction.
Understanding the Noise Challenge in Aviation
Noise reduction is a significant challenge in the aviation industry. High noise levels not only affect the passenger experience but also contribute to environmental noise pollution. It’s in the interest of airplane manufacturers like Boeing to minimize this as much as possible.
In an airplane engine, there are two types of airflow – the hot air coming from the combustion process inside the engine, and the cooler bypass air that flows outside the engine. When these two streams meet, they create noise. This is where chevrons come into play.
Role of Chevrons in Noise Reduction
The chevrons on the engines of Boeing 747-8, 787, and 737 MAX are engineered to reduce the noise generated during the aircraft’s operation. They work by smoothing the interaction between the hot air and the cooler bypass air. The saw-tooth pattern breaks down the cooler air into smaller “vortices,” reducing the noise created when the two streams meet. This ingenious solution helps to make the aircraft quieter, improving the flight experience for passengers and reducing noise pollution for those on the ground.
The Future of Chevrons
Boeing first introduced the chevron design in the 787 Dreamliner. The results were so impressive that the company decided to incorporate the feature into other aircraft, including the 747-8 and the 737 MAX. As a result, these planes have become some of the quietest in their classes.
Interestingly, the soon-to-be-released 777-9X and 777-8X are noticeably missing the distinctive chevrons. This modification comes as a result of substantial progression in engine technology.
The engines for Boeing’s 777X series are the product of General Electric Company (GE), and they’ve ushered in a new wave of engine innovation with their GE9X model. These ground-breaking engines employ a range of high-tech features that make it possible for them to function quietly and efficiently, removing the necessity for the chevron design.
The GE9X engines are adept at reducing noise, a feat achieved through refined aerodynamic design, an increased fan diameter, and a higher bypass ratio. The latter permits more air to go around the engine’s combustion section. As this bypass air is cooler and travels at a lesser speed, it reduces the noise produced when it comes into contact with the hot air that’s quickly exiting the combustion process.
First love never dies. I fell in love with airplanes and aviation when I was a kid. My dream was to become a pilot, but destiny led me to another path: to be an aviation digital media content creator and a small business owner. My passion for aviation inspires me to bring you quality content through my website and social accounts. Aviation is indeed in my blood and blog!
