AIRCRAFT ENGINELecture 4

1903- 1940sPropeller + Piston

Engines Era

History of Aircraft Propulsion From 1903 (Wright bros.) until the Early 1940s, all aircraft

used the piston engine combined with propeller as their propulsion system.

Piston engine is just similar with car engine except with several different.

A propeller is essentially a type of fan which transmits power by converting rotational motion into thrust.

Aircraft Piston Engines

In-Line engineRotary Engine

Radial EngineV-type EngineOpposed

Propeller + PistonEngine Aircraft

The engine takes air from the surroundings, mixed it with fuel, burns the fuel, fuels energy release, the energy of the heated gas exhaust is used to move a piston that is attached to a crankshaft.

Crankshaft turn the propeller to generate the thrust.

Thrust

Propeller: Acts as a rotating wing, creating a thrust force because of its motion through

the air.

Car Engines

Car EnginesValves The intake and exhaust valves open at the proper time to

let in air and fuel and to let out exhaust. Spark plug The spark plug supplies the spark that ignites the air/fuel

mixture so that combustion can occur. Piston A piston is a cylindrical piece of metal that moves up and

down inside the cylinder.Crankshaft The crankshaft turns the piston's up and down motion

into circular motion.

What are the differences between piston engines and car engines

The differences between piston aircraft engines and car engines Crankshaft – The crankshaft in an piston aircraft engine

turns a propeller, crankshaft in car engine is used to move the wheels of the car.

Weight – the piston aircraft engine must be lightweight compare to car engine.

Power demand to run the engines- the piston aircraft engine demands high power for very long times compare to car engines

Numbers of engine parts - an aircraft engine has at least two sets for every parts, including ignition system (spark plugs and magnetos) and fuel pumps compare to car engine that only have one set.

Operating environment different- an aircraft engine no need radiator for air-cooling compare to the car.

Propeller Aircraft

Very efficient for low speed flight. Lower load capacity compared to similar sized jet

powered aircraft. Consumes less fuel, thus cheaper and much more

economic than jets. Quiet, but fly at lower speeds. The best option for people who need to transport a

few passengers and/or small amounts of cargo. Best choice for pilots who wish to own their own

aircraft. Propellers are not used on high speed aircraft.

1941- TodayJet Engines Era

Jet Aircraft History

1939: The 1st jet aircraft (Heinkel He 178) was developed in England and Germany

1943: The first jet fighter aircraft, Messerschmitt Me 262 went into service in the German Luftwaffe.

Heinkel He-178(1939): 1st jet engine aircraft

1931: 1st turbojet engine

designed 1930 by Sir

Frank Whittle

Jet Engines HistoryJet Engines History Used for Lockheed

SR71 Blackbird

Fastest in 1989 Now retired

• Dr. Hans von Ohain•designer of turbojet

engine

History of Aircraft Propulsion

1944 (After World War 2)-Today : Airplanes used jet engines to generate thrust. Jet engines also referred to as Gas Turbine

Engines. Various types (turbo-jet, turbo-prop, turbo-shaft,

turbo-fan , ramjet, scramjet) Messerschmitt Me-262 : 1st operational jet-powered

aircraft German V-1 bomb (pulse jet engine): 1st application

for military purposes. Bell P-59: 1st American aircraft MiG-15: 1st Soviet jet aircraft.

Jet Aircraft

Jet aircraft make use of turbines for the creation of thrust.

Consumes more fuel but provide much more thrust than a piston engine.

Fly faster than propeller driven aircraft. Greater weight capacity Example: Airbus A340 and Boeing 777, can carry

hundreds of passengers and several tons of cargo, and are able to travel for distances up to 13 thousand kilometers.

Noisy, this makes jet aircraft a source of noise pollution.

Turbo-jet Engine A turbojet is a type of gas turbine engine that

was originally developed for military fighters during World War II.

A turbojet is the simplest of all aircraft gas turbines.

Newton's 3rd law

The theory of jet propulsion is based on the Newton’s third Law, which state that For every action there is an equal and opposite reaction.

When the jet engine is operating, it draws a lot of air from the front and after air-fuel burns the gas ejects at high speed.

During this process, the engine applies force to the gas and lets the gas accelerate in the backward direction and in the meantime, the gas also gives the engine a reactive force to push the aircraft to move forward.

Turbo-jet Engine

Inlet- inlet is the opening at the front of engine, it allows the outside air to enter the engine.

Compressor – compressor is made up of fans with many blades, it compress the air and raises the pressure & temperature of the air, the compressed air then is delivered to the burner.

Burner – Burning process occur here. Fuel is sprayed to the compressed air .The mixture of the fuel + air will be burned. The results is heated gas with high energy, high pressure and high temperature.

Turbine- turbine used some of the heated gas energy to turn the compressor . This energy is transferred through the shaft.

Nozzle- The balance of heated gas energy exits through the nozzle at very high speed. This causes thrust. As the jets of gas shoot backward, the engine and the aircraft are thrust forward.

(Newton 3rd Law)

Thrust

Newton's 3rd law: For every action there is an equal and opposite reaction. This is called thrust.

Turbojet Engine

Turbojet Engine

Cross section of turbojet engine

Turbo-prop Engine

•The propeller located at the front of engine •The propeller converts the power developed by the engine into thrust as efficiently as possible under all operating conditions.These aircraft are popular with commuter and regional airlines, as they tend to be more economical on shorter journeys.

Hercules-1 C130

Turbo-prop Engine

Jetstream 32

PC-7 & PC-7 MkII  CN235-220M

C-130H

Turbo-fan Engine

Similar to the turboprop, except a fan replaces the turboprop propeller.

Larger fan at the front provides thrust in the same way as a propeller. The turbofan engine has a front fan, which runs at the same speed as

the compressor and fan turbine located at the back to drive the fan. Most modern airliners use turbofan engines because of they can

produce high thrust, lower fuel consumption and low engine-noise.

Turbo-fan Engine

Pratt & Whitney F100 turbofan engine for the F-15 Eagle and the F-16 Falcon

Ramjet & Scramjet

Ramjet & Scramjet aircraft are in the experimental stage.

Question?

What is the different between piston aircraft engine and car engine?

What is the different between a propeller aircraft and jet aircraft?