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Turbojet

technology Maturity 7-9

A jet engine helps planes fly fast.

JetEngineGraph2.PNG
JetEngineGraph2.PNG
It pulls in air. Then it makes the air hot. The hot air shoots out the back. This push makes the plane go.
J85 ge 17a turbojet engine.jpg
J85 ge 17a turbojet engine.jpg
Can you imagine flying that fast?

42 words

A jet engine helps planes fly very fast.

JetEngineGraph2.PNG
JetEngineGraph2.PNG

First, the engine pulls in air. A part inside squeezes the air tight. This makes the air very hot.

J85 ge 17a turbojet engine.jpg
J85 ge 17a turbojet engine.jpg

Next, fuel is added to the hot air. The fuel burns to make more heat. This makes the air grow and move.

The hot air shoots out the back. This push helps the plane fly.

Axial compressor.gif
Axial compressor.gif

Two men helped make these engines work. They lived a long time ago. Now, many planes use them to travel.

90 words

A turbojet is a type of engine used in many aircraft.

JetEngineGraph2.PNG
JetEngineGraph2.PNG
It works by using a gas turbine to create thrust. Thrust is the push that moves a plane forward.

First, the engine pulls in air through an intake. This air goes into a compressor. A compressor is a part that squeezes air into a small space. Squeezing the air makes it very hot and high in pressure.

Next, the air enters a combustion chamber. In this part, fuel is added and burned. This makes the hot air expand quickly. The air then flows through a turbine. A turbine is a set of blades that spins as the air passes through. This spinning turbine provides the power to run the compressor.

Finally, the air shoots out through a propelling nozzle. The air moves at a very high speed. This fast spray of air provides the push to fly.

Axial compressor.gif
Axial compressor.gif

Two engineers helped make this possible. Frank Whittle worked in the United Kingdom. Hans von Ohain worked in Germany. They both developed these engines in the late 1930s.

Frank Whittle CH 011867.jpg
Frank Whittle CH 011867.jpg
The first aircraft to fly using a turbojet was the Heinkel He 178.
Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg

201 words

A turbojet is an airbreathing engine used to power aircraft. It works by using a gas turbine to create thrust. Thrust is the push that moves a plane through the sky. These engines are very important for fast travel. They allowed planes to fly much faster than old propeller engines.

JetEngineGraph2.PNG
JetEngineGraph2.PNG
Most modern fighters use even newer versions called turbofans. However, turbojets are still used for medium range cruise missiles. This is because they are simple and have a small frontal area.
J85 ge 17a turbojet engine.jpg
J85 ge 17a turbojet engine.jpg

There is a specific way this engine works. First, air enters through an intake or a tube. This intake helps guide the air smoothly into the engine. Next, the air goes into a compressor. The compressor squeezes the air into a smaller space. This squeezing makes the air much hotter and increases its pressure.

Axial compressor.gif
Axial compressor.gif
Then, the air enters a combustion chamber where fuel is burned. The hot, expanding air flows through a turbine. This turbine spins and provides the power to run the compressor. Finally, the air shoots out of a propelling nozzle at high speed.
Turbojet operation- axial flow.png
Turbojet operation- axial flow.png

Two engineers developed this idea at the same time. Frank Whittle worked in the United Kingdom during the late 1930s. He submitted his first patent in England on 16 January 1930. His team ran the first liquid-fuelled engine on 12 April 1937. In Germany, Hans von Ohain was also working on engines. He patented a similar design in 1935.

Frank Whittle CH 011867.jpg
Frank Whittle CH 011867.jpg
While Whittle used a centrifugal compressor, von Ohain used an axial-flow design. Most manufacturers eventually chose the axial-flow type by the 1950s.

History shows many important first flights for these engines. The Heinkel He 178 was the first aircraft to fly on turbojet power. It used von Ohain's design and was flown by Erich Warsitz on 27 August 1939.

Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg
In Britain, the Gloster E.28/39 made the first jet flight in 1941. The first operational jets entered service in 1944. These were the Messerschmitt Me 262 and the Gloster Meteor. The Me 262 was produced in large numbers, with up to 1400 made.
Whittle Jet Engine W2-700.JPG
Whittle Jet Engine W2-700.JPG

Turbojets changed how we travel across the world. Before jets, planes were less reliable and had many engines. Many early planes had four engines to stay safe. Turbojets are much more reliable than older piston engines. Some models have a reliability rating of over 99.9 percent. This allowed planes to have only two or three engines.

Jumo 004.jpg
Jumo 004.jpg
Because of this, planes can now fly long, direct routes. The Concorde was a famous plane that used turbojets to fly very fast. It could travel at Mach 2.2 to reach its destination quickly.

456 words

A turbojet is an airbreathing jet engine used to power aircraft. It is a type of gas turbine engine that creates thrust to move a vehicle forward. This engine is essential for high-speed flight because it replaces traditional propellers with a high-speed jet of exhaust. While turbojets are less efficient at low speeds, they are perfect for supersonic travel. Today, they are still used in medium-range cruise missiles due to their simplicity and small frontal area.

JetEngineGraph2.PNG
JetEngineGraph2.PNG

The engine works through a specific sequence of steps to turn air into motion. First, air enters through an intake or tube. This intake directs air smoothly into the engine and helps manage pressure. Next, the air enters a compressor. The compressor uses rotating blades to squeeze the air into a smaller space, which increases its pressure and temperature.

Axial compressor.gif
Axial compressor.gif
After compression, the air moves into a combustion chamber. Here, fuel is mixed with the compressed air and burned. The resulting hot, expanding gases flow through a turbine. This turbine extracts energy from the gas to spin the compressor, keeping the cycle going. Finally, the remaining gas expands through a propelling nozzle. This nozzle accelerates the exhaust to a very high speed to provide thrust.
Turbojet operation- axial flow.png
Turbojet operation- axial flow.png

There are two main types of compressors used in these engines: centrifugal and axial. A centrifugal compressor, like the one used in early Whittle engines, throws the air outward from the center. An axial compressor, like the one in the Junkers Jumo 004, keeps the airflow parallel to the axis of thrust.

Jumo 004.jpg
Jumo 004.jpg
Most manufacturers eventually moved toward axial designs by the 1950s because they allow for a smaller engine diameter. While turbojets provide direct thrust, a related design called a turboshaft uses an extra turbine to drive a rotating shaft. Turboshafts are commonly used to power helicopters and hovercraft.

The history of the turbojet involves two engineers working independently in the late 1930s. In the United Kingdom, Frank Whittle developed the concept and filed his first patent in 1930. His team successfully ran the first liquid-fuelled Power Jets WU engine on 12 April 1937. In Germany, Hans von Ohain patented a similar engine in 1935. On 27 August 1939, the Heinkel He 178 became the first aircraft to fly using von Ohain's turbojet design.

Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg
In Britain, the Gloster E.28/39 made the first jet-engined flight in 1941.
Whittle Jet Engine W2-700.JPG
Whittle Jet Engine W2-700.JPG

By 1944, the first operational turbojet aircraft entered service. The Messerschmitt Me 262 entered service in April, while the Gloster Meteor followed in July. The Me 262 was produced in large numbers, with up to 1,400 units manufactured. These engines changed aviation by allowing much higher speeds than piston engines. However, early engines faced challenges with heat. Without advanced materials, early non-UK engines had to be overhauled every 10 to 20 hours to prevent damage. British engineers used Nimonic alloys to improve durability, allowing some engines to run for 500 hours without maintenance.

The development of high-temperature materials was vital for engine progress. Engineers had to create superalloys and cooling designs to handle the intense heat of the turbine. In the early days, pilots even had to monitor turbine temperatures manually to avoid damage. Some early engines used water injection during takeoff to increase thrust without exceeding temperature limits. This method increased thrust but often left a visible smoke trail because it prevented complete combustion. As technology improved, automatic temperature limiting was introduced to help pilots.

J85 ge 17a turbojet engine.jpg
J85 ge 17a turbojet engine.jpg

Turbojets had a massive impact on the reliability of commercial aviation. Older piston engines were less reliable, often requiring planes to carry four engines for safety. Turbojets can reach dispatch reliability ratings of over 99.9 percent. This high reliability allowed designers to build planes with only two or three engines. This change enabled more direct, long-distance flight paths. The Concorde is a famous example of a plane that used turbojets to maintain supersonic speeds.

Frank Whittle CH 011867.jpg
Frank Whittle CH 011867.jpg
Even at Mach 2.2, the engine efficiency of the Concorde helped manage the high drag of supersonic flight.

682 words
🖼️ Images & Media (10)
File:Jumo 004.jpg
Jumo 004.jpg
File:JetEngineGraph2.PNG
JetEngineGraph2.PNG
File:Frank Whittle CH 011867.jpg
Frank Whittle CH 011867.jpg
File:Ohain.jpg
Ohain.jpg
File:Ohain USAF He 178 page61.jpg
Ohain USAF He 178 page61.jpg
File:Whittle Jet Engine W2-700.JPG
Whittle Jet Engine W2-700.JPG
File:J85 ge 17a turbojet engine.jpg
J85 ge 17a turbojet engine.jpg
File:Axial compressor.gif
Axial compressor.gif
File:Turbojet operation- centrifugal flow.png
Turbojet operation- centrifugal flow.png
File:Turbojet operation- axial flow.png
Turbojet operation- axial flow.png
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