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AVIATION HISTORY AVH 1104. WEEK 6: CHAPTER 4. Outlines. Basic Aircraft Propulsion System Aircraft Engines Aircraft Control System Basic Helicopter. A Brief History of Flight. 1. 1783, 1 st true hot-air balloon (Montgolfier bros in France).
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AVIATION HISTORYAVH 1104 WEEK 6: CHAPTER 4
Outlines • Basic Aircraft • Propulsion System • Aircraft Engines • Aircraft Control System • Basic Helicopter
A Brief History of Flight 1. 1783, 1st true hot-air balloon (Montgolfier bros in France) 2. 1804, 1st successful glider (George Cayley) 3. 1891, 1st glider in which the glider could be piloted (Otto Lilienthal) 4. 1903, 1st aircraft (Wright bros.)
A Brief History of Flight 5. 1927, 1st pilot set out on an historic flight across the Atlantic Ocean, form New York to Paris (Charles Lindbergh) 6. 1936, 1st helicopter (Focke-Wulf Fw 6) 6. 1939, 1st jet aircraft (Heinkel He-178) 7. 1947, 1st supersonic aircraft (Bell XS-1) 8. 1950s -Today……..the aircraft technologies continuously expanding and there are always many researches have been established in order to improve the aircraft performances.
Basic Aircraft • Fuselage: • Central body portion: To accommodate the crew, the passengers, and the cargo. • Streamlined as much as possible to reduce drag. • Wing (fixed): • The purpose of wing is to generate lift (because of the airfoil shape) • Ailerons (movable)= To provide roll control. • Flap = To create additional lift to the aircraft (especially during take-off) • Spoilers = To interrupt the air flow over the wing (to slow down the a/c during landing) Various shape of airfoils
Basic Aircraft • Tail: • Vertical Stabilizer , rudder (movable)-yaw control • Horizontal Stabilizer , elevator (movable)-pitch control • Power Plants (Engine/propeller) • To generate thrust that propels the aircraft • Propeller • Gas Turbine • Landing Gear: • Tricycle gear: nose wheel, two main wheels • Conventional gear: tail wheel, two main wheels • Unconventional gear: skis, skids, or floats
Aircraft Performance • Speed: What is the minimum and maximum speed of the aircraft. • Range: How far can the aircraft fly with a tank of fuel. • Endurance: How long can the aircraft stay in the air with a tank of fuel.
Forces on Aircraft • For flight, an aircraft's lift must balance its weight, and its thrust must exceed its drag. • A plane uses its wings for lift and its engines for thrust.
Forces on Aircraft • Lift • This force is generated by the flow of air around the aircraft, the major portion resulting from the wing. • Weight • The weigh includes the aircraft itself, the payload and the fuel. • Since fuel is consumed as the aircraft flies, the weight decreases. • Weight acts in a direction toward the center of the Earth. • Drag • Basically, any object that is moving through the air will experience resistance. This resistance is called drag. • Similar to lift, this force also arises from the flow around the aircraft but it is component of the resultant aerodynamic force along the line of flight. • Wing is designed to be smooth in order to reduce drag. • Drag important during landing in order to slow down the aircraft. • Thrust • The force that moves the aircraft through the air. • Generate by the propulsion system • (E.g., engine driver propeller, jet engine, rocket engine). • It may be taken to act along the longitudinal axis of the aircraft.
Lift Fast flowing air The shape of airfoil The greater surface area on the top makes the air velocity flows faster on the top & vice versa. Slow flowing air • An aircraft flies due to the aerodynamic reactions that happen when air passes over the wing.
Aircraft Control System • Moving Surfaces of an aircraft • Yaw Control- Rudder : Turning the a/c to left or right. • Pitch Control- Elevators: Nosing the aircraft up and down. • Roll Control- Ailerons: Rolling the wing to the right or left. 13
Origins of Control Surfaces 1908 1st aircraft featured fixed vertical and horizontal tails with movable rudder and elevator surfaces attached to their trailing edges. 1910 1st aircraft equipped with four flap-like ailerons fitted at the outboard trailing edges of both the upper and lower wings. Henri Farman and the Farman III Léon Levavasseur and the Antoinette IV Glenn Curtiss, Alexander Graham Bell, and the June Bug showing its ailerons 14
History of Aircraft Propulsion • 1903 (Wright bros.) – 1943 : Piston Engines • Airplanes used internal combustion engines to turn propellers to generate thrust (propeller aircraft) • 1st aircraft by Wright bros.: Kitty Hawk A World War I wooden aircraft propeller • 1944 (After World War 2)-Today :Jet Engines • Airplanes used jet engines to turn propellers/shaft/fan to generate thrust. • Jet engines also referred to as Gas Turbine Engines. • Various types (turbo-jet, turbo-prop, turbo-shaft, turbo-fan , ramjet, scramjet) • German V-1 bomb (pulse jet engine): 1st application for military purposes. • Messerschmitt Me-262 : 1st operational jet-powered aircraft • Bell P-59: 1st American aircraft • MiG-15: 1st Soviet jet aircraft.
Propeller Aircraft Thrust • Propeller: Acts as a rotating wing, creating a thrust force because of its motion through the air. • Similar to automobile engines. • The engine takes air from the surroundings, mixed it with fuel, burns the fuel (fuels energy release), the heated gas exhaust is used to move a piston that is attached to a crankshaft. • **Automobile: shaft is used to move the wheels of the car. • **Airplanes: The shaft turns a propeller The propellers of an RAF Hercules C.4 in feather position
Propeller Aircraft • Very efficient for low speed flight. • Lower load capacity compared to similar sized jet powered aircraft. • 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.
Piston Engines • Piston Engine: • Converts the heat energy of the fuel and burns it into mechanical energy. • Inducing air and fuel mixture into a cylinder. Rotary Engine In-Line engine Radial Engine Opposed V-type Engine
Jet Aircraft • Jet aircraft make use of turbines for the creation of thrust. • Much more powerful than a piston engine. • Greater weight capacity and fly faster than propeller driven aircraft. • 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.
Jet Aircraft History • Sir Frank Whittle • 1st turbojet patent • 1930 (23 years old) • 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 engined aircraft
Jet Engines History Used for Lockheed SR71 Blackbird • Dr. Hans von Ohain • 1st designer of turbojet engine Fastest in 1989 Now retired
Gas Turbine Engine Thrust • All jet engines, which are also called gas turbines, work on the same principle. • Inletbrings free stream air into the engine. • A compressor raises the pressure & temperature of the air. • The compressor is made up of fans with many blades and attached to a shaft. • The blades compress the air. • In the burner, the compressed air is then sprayed with fuel and an electric spark lights the mixture. • The burning gases expand and blast out through the nozzle, at the back of the engine. • As the jets of gas shoot backward, the engine and the aircraft are thrust forward. Newton's 3rd law: For every action there is an equal and opposite reaction. This is called thrust.
Turbo-prop • Turboprop aircraft are a halfway house between propeller and jet: they use a turbine engine similar to a jet to turn propellers. • These aircraft are popular with commuter and regional airlines, as they tend to be more economical on shorter journeys. Hercules-1 C130
Turbo-fan Enlarged Fan Fan • Most modern airliners use turbofan engines because of their high thrust and good fuel efficiency. • The core engine is surrounded by a fan in the front and an additional fan turbine at the rear. • Larger fan at the front provides thrust in the same way as a propeller. • 1st engine to use multiple spools (concentric shafts which are free to rotate at their own speed-can quickly change the power requirements)
Supersonic Aircraft • If subsonic aircraft has Mach No.< 1, supersonic aircraft a/c has Mach No. >1 • Supersonic aircraft, such as military fighters and bombers, Concorde, and others, make use of special turbines (afterburners), that generate the huge amounts of power for flight faster than the speed of the sound. • Due to the high costs, limited areas of use and low demand there are no longer any supersonic aircraft in use by any major airline. The last Concorde flight was on 26 November 2003. 1975, 1st supersonic transport aircraft (Tupolev Tu-144)
Ramjet • Ramjet aircraft are mostly in the experimental stage.
Scramjet • Scramjet aircraft are in the experimental stage. • The Boeing X-43 is an experimental scramjet with a world speed record for a jet-powered aircraft - Mach 9.6, or nearly 7,000 mph. The X-43A set the flight speed record on 16 November 2004.
Aircraft Fuel • For the first few decades of flight, aircraft engines simply used the same kind of gasoline that powered automobiles. • But simple gasoline was not necessarily the best fuel for the large and powerful engines used by most piston-engines airplanes that were developed in the 1930s and 1940s. • Thereby, most airplanes carried AvGas (Aviation Gasoline) • Jet fuel (AvTur: Aviation Turbine Fuel) is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. • The most common fuels are Jet A and Jet A-1’ • Jet B is commonly used in civilian turbine engine-powered and is used for its enhanced cold-weather performance.
Question? • What is the different between a propeller aircraft and jet aircraft?
Rocket History • A rocket or rocket vehicle is a missile, aircraft or other vehicle which obtains thrust by the reaction of the rocket to the ejection of fast moving fluid exhaust from a rocket engine. • 1926: 1st Rocket launched by Robert H. Goddard (liquid-fueled), reached only modest height of 12.5m. • 1957: 1st satellite (Sputnik-1) launched to the space by the Russian
Rocket Engine • A rocket engine produces thrust by burning a fuel at high pressure and exhausting the gas through a nozzle. The oxygen for combustion is carried with the propulsion system. • Operate with either solid or liquid propellants. • Solid-propellant: contain both the fuel (H2+C) & oxidizer(O2 )combined together in the chemicals. • Liquid-propellant: liquid fuel and oxidizers kept in different tanks. • High temperatures and pressures is built up, the are used to accelerate the exhaust gases through a rocket nozzle to produce thrust. • The heavier the rocket , the greater thrust needed to get it off the ground. • Newton 3rd Law: “To every action there is an equal and opposite reaction."
Basic Helicopter Blades The cross section of the helicopter blades have the same shape as the airfoil on the airplane wings, thus the principle on how lift is created is similar for both of helicopter and airplane
How Helicopter Flies • A helicopter can take off and land vertically (straight up and down). • It can fly in any direction, even sideways and backwards. • It can also hover or hang in the air above a given place. • A helicopter gets its power from rotors or blades. • When its rotors are spinning, a helicopter doesn't look much like an airplane. • But the rotor blades have an airfoil shape like the wings of an airplane. • So as the rotors turn, air flows more quickly over the tops of the blades than it does below. • This creates enough lift for flight.
Airplane Vs Helicopter • A helicopter engine rotates the airfoil (rotor blade) that produces the lift so that the machine can lift itself vertically. • An airplane generates lift over its wings by the engine translating the airfoil (wing) through the air. • The helicopter engine rotates the "wing" to produce lift and the airplane engine pulls (or pushes) the wing through the air to generate lift. • The operational differences come from the aerodynamic physics associated with these two different ways of moving the airfoil. The helicopter rotors (wings) must change their relative angle to the air flows as they rotate . This makes the blade positioning system very complex, heavy and expensive, and the helicopter more difficult to stabilize than a conventional airplane. • Thus, the helicopter is heavier and more expensive than a conventional airplane (and therefore can carry less payload with the same engine power), • However, its ability to land and take-off vertically, and hover in mid-air, give it an advantage in certain applications.
ASSIGNMENT QUESTION FOR AVIATION HISTORY Aviation has progressed so fast since the Wright Brothers first flew in 1902. Airline aircrafts have become faster and more economical to operate; and from single aisle to wide cabin and from canvas to composite and from subsonic to supersonic and single to double deck and from mechanical instruments to glass cockpit etc. Explain what are the future challenges that the civil aviation would face. All assignments must have font 12, not be more than 15 pages at 1.5 line spacing. Provide table of content and bibliography at the end of the end of the assignments together with the declaration format. No plagiarism, therefore those with duplicated assignments will be penalised. Deadline: 15 October 2009 (Thursday) at 5.30pm. Delay penalty: one mark each day.