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Jet engine

technology Maturity 9-11

A jet engine helps planes fly.

20140308-Jet engine airflow during take-off.jpg
20140308-Jet engine airflow during take-off.jpg
It blows hot air out the back. This push makes the plane go fast. It helps us travel far away. We can fly in big planes. Do you like to fly?
JT9D on 747.JPG
JT9D on 747.JPG

45 words

A jet engine helps planes fly.

20140308-Jet engine airflow during take-off.jpg
20140308-Jet engine airflow during take-off.jpg
It blows hot air out the back. This push makes the plane go fast.
Jet engine.svg
Jet engine.svg
The engine pulls in air. It uses a spinning part to squeeze the air. Then it burns fuel to make heat. This heat pushes the air out very fast.
JT9D on 747.JPG
JT9D on 747.JPG
This helps big planes fly far away. It is a very strong way to move.

74 words

A jet engine is a powerful tool. It helps planes fly long distances.

20140308-Jet engine airflow during take-off.jpg
20140308-Jet engine airflow during take-off.jpg
It works through jet propulsion. This means the engine blows hot gas out the back. That push makes the plane move forward.
Jet engine.svg
Jet engine.svg

Most jet engines are air-breathing. This means they take in air from outside. Inside, a part called a compressor squeezes the air. A turbine, which is a spinning part, helps power this.

Junkers Jumo 004.jpg
Junkers Jumo 004.jpg
Then, fuel is added and burned. This makes the air very hot and fast. The air leaves through a nozzle. This set of steps is called the Brayton cycle.
Turbofan operation lbp.svg
Turbofan operation lbp.svg

Many modern planes use a turbofan engine. These are very good at saving fuel. In the 1950s, engines were not as reliable. Now, they are much safer to use. They can even power big ships or even cars. Some engines are also used to make power for electricity. This makes the jet engine a very important part of our world.

169 words

A jet engine is a special kind of engine that creates movement. It works using jet propulsion. This means the engine pushes out a fast stream of hot gas. This push creates thrust, which moves the vehicle forward.

Jet engine.svg
Jet engine.svg
Most engines used on planes are air-breathing. They take in air from the sky to work. This allows them to travel very long distances.
20140308-Jet engine airflow during take-off.jpg
20140308-Jet engine airflow during take-off.jpg

These engines follow a specific way of working called the Brayton cycle. First, a rotating air compressor squeezes the incoming air. Next, fuel is added to this squeezed air and burned. This makes the air very hot and causes it to expand. The hot air then rushes through a propelling nozzle at the back. This final step provides the thrust needed to fly.

Turbofan operation lbp.svg
Turbofan operation lbp.svg

People have thought about jet power for a long time. In 1st-century Egypt, Hero of Alexandria described a spinning sphere powered by steam. Later, in 1633, a soldier named Lagâri Hasan Çelebi reportedly flew using a rocket. In the 1700s, John Barber patented a stationary turbine in England. By 1937, Hans von Ohain and his team flew the He 178. This was the world's first jet plane.

Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg

Engine technology has changed a lot over the years. In the 1950s, engines like the de Havilland Ghost were used. By the 1990s, the General Electric GE90 became a powerful turbofan. Reliability has improved greatly since then. In the past, there were 40 engine shutdowns per 100,000 flight hours. Now, there is less than 1 shutdown per 100,000 hours.

JT9D on 747.JPG
JT9D on 747.JPG

Today, you can see jet engines in many different places. Most large civilian planes use high-bypass turbofan engines. These engines are very good at saving fuel. Some jet designs even power fast cars or large ships. They can even be used to make electricity.

Junkers Jumo 004.jpg
Junkers Jumo 004.jpg
Even rockets use the same basic idea of jet propulsion to reach space.

329 words

A jet engine is a type of reaction engine that generates movement through jet propulsion. This process involves discharging a fast-moving jet of heated gas to create thrust. While the term can include rockets or water jets, it usually refers to air-breathing internal combustion engines. These engines are vital for modern aviation and long-distance travel. They allow aircraft to fly much faster and more efficiently than older propeller engines.

Jet engine.svg
Jet engine.svg

Most air-breathing jet engines operate using the Brayton thermodynamic cycle. This cycle is a step-by-step process of energy conversion. First, a rotating air compressor pulls in air and squeezes it tightly. Next, fuel is mixed with this compressed air and ignited in a combustion chamber. This burning process makes the air extremely hot and causes it to expand rapidly. Finally, the expanding air rushes through a propelling nozzle at the back of the engine. This high-speed exhaust creates the thrust that pushes the aircraft forward.

Turbofan operation lbp.svg
Turbofan operation lbp.svg

Engine designers use different configurations depending on the speed of the vehicle. Early jet aircraft relied on turbojet engines, which were less efficient for subsonic flight. Most modern subsonic planes now use high-bypass turbofan engines. These engines are more complex but offer much greater fuel efficiency. For very high-speed applications, engineers use ramjets or scramjets. These specialized engines do not use a mechanical compressor. Instead, they use the ram effect caused by the vehicle's own high speed to compress the incoming air.

Gas turbine efficiency.png
Gas turbine efficiency.png

The history of jet propulsion spans many centuries and different cultures. A very early demonstration was the aeolipile in 1st-century Egypt. This device used steam to spin a sphere on its axis. Later, traditional Chinese rocket propulsion provided theoretical roots for these principles. In 1633, an Ottoman soldier named Lagâri Hasan Çelebi reportedly flew using a cone-shaped rocket. In 1791, John Barber in England patented a stationary turbine. However, it took many more years to create a self-sustaining gas turbine. The first successful one was built by Ægidius Elling in 1903.

Whittle Jet Engine W2-700.JPG
Whittle Jet Engine W2-700.JPG

The 20th century brought the breakthrough of practical aircraft engines. Frank Whittle submitted his ideas for a turbojet in England in 1930. At the same time, Hans von Ohain worked on similar designs in Germany. In 1939, Ohain’s team flew the He 178, the world's first jet plane. During World War II, the German Junkers Jumo 004 became the first jet engine used in service. It powered the Messerschmitt Me 262 fighter. Soon after, the British Gloster Meteor also entered service.

Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg

Engine technology has seen massive improvements in both power and reliability. In the 1950s, engines like the de Havilland Ghost were common. By the 1990s, the General Electric GE90 turbofan represented a massive leap in power. Reliability has grown significantly over these decades. In the mid-20th century, there were 40 in-flight shutdowns per 100,000 engine flight hours. By the late 1990s, that number dropped to less than one per 100,000 hours. This reliability, plus better fuel economy, made routine transatlantic flights possible.

JT9D on 747.JPG
JT9D on 747.JPG

Today, jet engine technology is used in many different fields beyond passenger planes. Some engines power cruise missiles or unmanned aerial vehicles. They are also used in rockets for spaceflight and military missiles. Engineers even use jet designs to power high-speed cars like the ThrustSSC. In industrial settings, gas turbines can generate up to 50,000 shaft horsepower. These machines can power water pumps, oil pumps, or electrical generators. Even helicopters use related gas turbine forms known as turboshafts.

Junkers Jumo 004.jpg
Junkers Jumo 004.jpg

591 words
🖼️ Images & Media (17)
File:20140308-Jet engine airflow during take-off.jpg
20140308-Jet engine airflow during take-off.jpg
File:CS-1 kisérleti repülőgép gázturbina.jpg
CS-1 kisérleti repülőgép gázturbina.jpg
File:Whittle Jet Engine W2-700.JPG
Whittle Jet Engine W2-700.JPG
File:Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg
File:Junkers Jumo 004.jpg
Junkers Jumo 004.jpg
File:Gloster Meteor III ExCC.jpg
Gloster Meteor III ExCC.jpg
File:JT9D on 747.JPG
JT9D on 747.JPG
File:Jet engine.svg
Jet engine.svg
File:Turbofan operation lbp.svg
Turbofan operation lbp.svg
File:Rocket thrust.svg
Rocket thrust.svg
File:Pump jet.PNG
Pump jet.PNG
File:Propulsive efficiency.png
Propulsive efficiency.png

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