What Do I Need To Know About My Jet Engine Exhaust System?

Today’s modern planes are generally powered by jet engines, or to be exact, gas turbines. While these engines are also used in racing trucks, motorcycles, and cars, they have some subtle to notable differences, depending on the vehicles they power.

In a nutshell, a jet engine is any class of internal combustion engine that propels an aircraft (or wheeled vehicle) using the rearward discharge of a jet fluid, which is usually hot exhaust gas released by burning fuel.

But to function properly, jet engines need an exhaust system. And in aircraft, exhaust plays more critical functions compared to cars and motorcycles.

Scroll below to learn more about jet engine exhaust, especially interesting facts about this amazing piece of technology.

How Does an Aircraft’s Jet Engine Exhaust System Work?

While wheeled vehicles only need a simple exhaust system, planes require a more sophisticated design because they need exhaust to vent gases away from the engine and fuselage, which in turn prevents fire, carbon monoxide poisoning, and loss of engine performance.

Pilots and aircraft owners need to understand the importance of regular inspections and tune-ups to keep the exhaust in its best condition.

Meanwhile, jet engine exhaust also indirectly supplies cabin and carburetor heat.

Jet Engine Exhaust Noise

Did you ever wonder why planes are so loud in the sky, especially in bad weather conditions?

The noise comes from two sources – the jet engine itself and the exhaust’s reaction to the surrounding air. Take note that once the hot exhaust leaves the turbine and nozzle, it travels faster than the surrounding air, resulting in the “unmusical” and deafening roar.

During adverse weather conditions, the jet engine noise becomes louder due to the extra turbulence from the high-velocity air exiting the nozzle and slamming against the low-velocity air outside. Scientists have a fancy name for this: amplification of turbulence fluctuation.

Aside from the shifting wind that can carry noise to farther distances, cloud coverage can also make the jet engine noise louder (or even scarier) when you’re on the ground. This phenomenon occurs since sound waves from the aircraft rebound to the earth’s surface from the bottom of the clouds.

Jet Engine Exhaust Temperature and Pressure

The exhaust system in aircraft is consistently exposed to extreme temperatures – between 1,200 to 1,400 degrees Fahrenheit). Additionally, its surface is continuously bombarded with the corrosive properties of hydrocarbon fuels, which can leave significant damage over time.

Due to the constant exposure to extreme temperatures, corrosive leftovers, and pressure, aircraft maintenance should always include the exhaust system. And if any of the components have signs of wear and tear, they should be repaired or replaced immediately to prevent issues like leaks, fire, poor engine performance, and carbon monoxide poisoning.

A Final Word About Jet Engine Exhaust Systems

Unlike cars that only need a simple exhaust, aircraft exhaust systems play critical functions, especially in engine performance. For this reason, licensed maintenance technicians pay close attention to signs of wear and tear, obstruction, and corrosion during engine and exhaust inspections.

An engine exhaust system that is in optimal condition (i.e., it has no obstruction or any sign of damage or corrosion) results in a quieter aircraft and better engine performance.