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Flight PowerFlight Power
Warm-Up QuestionsWarm-Up Questions
CPS Questions 1-2 CPS Questions 1-2
Chapter 1, Lesson 5
Lesson OverviewLesson Overview
The principles of Boyle’s Law, Charles’s The principles of Boyle’s Law, Charles’s Law, and Gay-Lussac’s LawLaw, and Gay-Lussac’s Law
The characteristics of internal The characteristics of internal combustion enginescombustion engines
The mechanical, cooling, and ignition The mechanical, cooling, and ignition systems of reciprocating enginessystems of reciprocating engines
Chapter 1, Lesson 5
Lesson Overview, cont.Lesson Overview, cont.
How the different types of jet engines How the different types of jet engines workwork
The role of reversers and suppressors The role of reversers and suppressors used in jet aircraftused in jet aircraft
Reaction enginesReaction engines The development of new engine The development of new engine
technologytechnology
Chapter 1, Lesson 5
Quick WriteQuick Write
Which is the more significant achievement – Which is the more significant achievement – being the first to invent something, or the being the first to invent something, or the
first to make it practical? Or are both first to make it practical? Or are both equally important? equally important?
(Note to teacher: Use “Pick a Student” button in CPS) (Note to teacher: Use “Pick a Student” button in CPS)
Chapter 1, Lesson 5 © Laser143/Dreamstime.com
Boyle’s LawBoyle’s Law Relationship between pressure and volume of a Relationship between pressure and volume of a
confined gas at a constant temperatureconfined gas at a constant temperature When pressure increased, the volume decreased, When pressure increased, the volume decreased,
when pressure decreased, the volume increasedwhen pressure decreased, the volume increased
Chapter 1, Lesson 5Chapter 1, Lesson 5 Reproduced from NASA/Glenn Research Center
Charles’s LawCharles’s Law
The volume of a gas is directly proportional to The volume of a gas is directly proportional to its temperatureits temperature
If temperature of a gas rises, its volume If temperature of a gas rises, its volume increases; if temperature falls, the volume increases; if temperature falls, the volume decreasesdecreases
Chapter 1, Lesson 5Reproduced from NASA/Glen Research Center
Gay Lussac’s LawGay Lussac’s Law Relationship between pressure of a gas, and Relationship between pressure of a gas, and
temperature, when the volume is constanttemperature, when the volume is constant Pressure rises when temperature rises, and Pressure rises when temperature rises, and
pressure falls when temperature fallspressure falls when temperature falls
Chapter 1, Lesson 5Reproduced from NASA/Glen Research Center
Activity 1: Activity 1: Animated Gas LabAnimated Gas Lab
View the Animated Gas Lab at the NASA View the Animated Gas Lab at the NASA websitewebsite
Use the lab to work through the questionsUse the lab to work through the questions
Chapter 1, Lesson 5
The Characteristics of Internal Combustion Engines
Internal combustion engines Internal combustion engines turn propellers which turn propellers which generate thrustgenerate thrust
Combustion processCombustion process— chemical energy converts to chemical energy converts to mechanical energymechanical energy
The piston compresses fuel The piston compresses fuel and air before combustion; and air before combustion; then is forced back down the then is forced back down the cylinder following combustioncylinder following combustion
Chapter 1, Lesson 5Reproduced from NASA/Glen Research Center
Learning Check QuestionsLearning Check Questions
CPS Questions 3-4CPS Questions 3-4
Chapter 1, Lesson 5
Activity 2: Activity 2: Internal Combustion Engine PartsInternal Combustion Engine Parts
Observe the four-stroke internal Observe the four-stroke internal combustion engine animation combustion engine animation
Label the engine parts and provide a Label the engine parts and provide a short descriptionshort description
Chapter 1, Lesson 5
Activity 2Activity 2—Four Stroke Four Stroke Internal Combustion Engine Internal Combustion Engine
Chapter 1, Lesson 5Reproduced from NASA/Glen Research Center
Reciprocating EnginesReciprocating Engines
Internal combustion engine is a Internal combustion engine is a reciprocating engine reciprocating engine
Back-and-forth movement of the pistons Back-and-forth movement of the pistons produces mechanical energyproduces mechanical energy
Most small aircraft have reciprocating Most small aircraft have reciprocating enginesengines
Parts include cylinders, pistons, Parts include cylinders, pistons, connecting rods, a crankshaft, crankcase, connecting rods, a crankshaft, crankcase, intake and exhaust valves, and spark intake and exhaust valves, and spark plugsplugs
Chapter 1, Lesson 5Reproduced from US Department of Transportation/Federal Aviation Administration
Intake Stroke—First Stroke Intake Stroke—First Stroke
Piston moves down, intake Piston moves down, intake valve opens, drawing air and valve opens, drawing air and fuel in at constant pressurefuel in at constant pressure
Provides great deal of surface Provides great deal of surface area that reacts quickly with area that reacts quickly with the oxygen in the airthe oxygen in the air
Chapter 1, Lesson 5 Reproduced from NASA/Johnson Space Center
Compression Stroke—Compression Stroke—Second Stroke Second Stroke
The piston reaches the bottom, The piston reaches the bottom, the intake valve closes, sealing the the intake valve closes, sealing the cylindercylinder
Volume decreases, the piston Volume decreases, the piston compresses the fuel-air mixture, compresses the fuel-air mixture, raising temperature and raising temperature and increasing pressure increasing pressure
Gas particles are close together, Gas particles are close together, can react quickly when ignitedcan react quickly when ignited
Chapter 1, Lesson 5 Reproduced from NASA/Johnson Space Center
Power or Ignition Stroke—Power or Ignition Stroke—Third Stroke Third Stroke
As the piston nears the top, a surge of As the piston nears the top, a surge of current is sent to spark plugcurrent is sent to spark plug
The Spark ignites the compressed fuel-air The Spark ignites the compressed fuel-air mixturemixture
Fuel rapidly combines with oxygen and Fuel rapidly combines with oxygen and produces carbon dioxide gas and water produces carbon dioxide gas and water vaporvapor
Hot gases force the piston down turning Hot gases force the piston down turning the crankshaftthe crankshaft
The crankshaft turns the aircraft propeller
Chapter 1, Lesson 5 Reproduced from NASA/Johnson Space Center
Exhaust Stroke—Exhaust Stroke—Fourth Stroke Fourth Stroke
Piston reaches the bottom and Piston reaches the bottom and starts back up the cylinder, the starts back up the cylinder, the exhaust stroke beginsexhaust stroke begins
The exhaust valve opens, The exhaust valve opens, residual heat is released, and residual heat is released, and pressure returns to pressure returns to atmospheric conditionsatmospheric conditions
The piston pushes waste gas The piston pushes waste gas out of the cylinderout of the cylinder
Chapter 1, Lesson 5 Reproduced from NASA/Johnson Space Center
CoolingCooling Air cooled systemAir cooled system—air flows through openings at the front of air flows through openings at the front of the engine cowling into the engine compartment the engine cowling into the engine compartment Hot air leaves the engine through openings in lower, aft portionHot air leaves the engine through openings in lower, aft portion
of the cowlingof the cowlingLiquid-cooled Liquid-cooled —requires the additional weight of a radiator and requires the additional weight of a radiator and liquidliquidRadiators pump air-cooled liquid in pipes around hot parts of an Radiators pump air-cooled liquid in pipes around hot parts of an engineengine
Chapter 1, Lesson 5Reproduced from US Department of Transportation/Federal Aviation Administration
Ignition SystemIgnition System
Provides the spark that ignites the fuel-air mixture in Provides the spark that ignites the fuel-air mixture in cylinderscylinders
Firing of two spark plugs improves combustion and Firing of two spark plugs improves combustion and results in more power; if one magneto fails, other can results in more power; if one magneto fails, other can still work on its ownstill work on its own
Chapter 1, Lesson 5 Reproduced from NASA/Glen Research Center
Chapter 1, Lesson 5
Learning Check QuestionsLearning Check Questions
CPS Questions 5-6CPS Questions 5-6
TurbojetsTurbojets
Engine is an open tube that burns fuel Engine is an open tube that burns fuel continuouslycontinuously
Main parts: compressor, combustion chamber, Main parts: compressor, combustion chamber, turbine, inlet, shaft, and nozzleturbine, inlet, shaft, and nozzle
Large air mass enters the inlet and is drawn Large air mass enters the inlet and is drawn into a rotating compressorinto a rotating compressor
Chapter 1, Lesson 5Reproduced from US Department of Transportation/Federal Aviation Administration
Turbojets, cont.Turbojets, cont. Compressor raises air pressure and forces the gas into Compressor raises air pressure and forces the gas into
smaller volumes, gas pressure increases and heats upsmaller volumes, gas pressure increases and heats up Fuel is injected into the combustion chamber, where it Fuel is injected into the combustion chamber, where it
ignitesignites Heated gas passes over turbine blades causing them to Heated gas passes over turbine blades causing them to
rotate shaft connected to compressorrotate shaft connected to compressor Nozzle’s purpose is to convert chemical energy into Nozzle’s purpose is to convert chemical energy into
mechanical energy, thus producing thrustmechanical energy, thus producing thrust
Chapter 1, Lesson 5
Turbofans Turbofans Modified turbojet engine - has additional turbine to turn a fan at Modified turbojet engine - has additional turbine to turn a fan at
front of the enginefront of the engine Two-spool engine; one powers compressor, other turns the large Two-spool engine; one powers compressor, other turns the large
fanfan Air from large fan enters the engine core, where fuel burns to Air from large fan enters the engine core, where fuel burns to
provide some thrustprovide some thrust 90 percent of the air bypasses the engine core; as much as 75 90 percent of the air bypasses the engine core; as much as 75
percent of the total thrust is from bypass airpercent of the total thrust is from bypass air
Chapter 1, Lesson 5Reproduced from US Department of Transportation/Federal Aviation Administration
Turboprops Turboprops
Hybrid of a turbojet and a propeller engineHybrid of a turbojet and a propeller engine Has a turbojet core to produce power but with Has a turbojet core to produce power but with
two turbinestwo turbines First turbine powers the compressor; the second First turbine powers the compressor; the second
turbine powers the propellerturbine powers the propeller
Chapter 1, Lesson 5Reproduced from US Department of Transportation/Federal Aviation Administration
RamjetsRamjets Ramjets work with another power source for Ramjets work with another power source for
initial thrust, such as a rocketinitial thrust, such as a rocket Operates by combusting fuel in a stream of air Operates by combusting fuel in a stream of air
compressed by aircraft’s forward motion compressed by aircraft’s forward motion Airflow is subsonic, less than the speed of soundAirflow is subsonic, less than the speed of sound
Chapter 1, Lesson 5Reproduced from NASA/Johnson Space Center
ScramjetsScramjets
Scramjets overcome Scramjets overcome the speed limitationthe speed limitation
It is a supersonic-It is a supersonic-combustion ramjetcombustion ramjet
Needs another engine Needs another engine or vehicle to accelerate or vehicle to accelerate it to operating speedit to operating speed
Chapter 1, Lesson 5Reproduced from NASA's Dryden Flight Research Center
Thrust ReversersThrust Reversers
Diverts thrust to the opposite Diverts thrust to the opposite direction of the aircraft’s motiondirection of the aircraft’s motion
Clamshell reverser forms a shield Clamshell reverser forms a shield at the back of the nozzle, at the back of the nozzle, deflects exhaust so it no longer deflects exhaust so it no longer produces forward thrustproduces forward thrust
Cascade reverser is a series of Cascade reverser is a series of airfoils with a high degree of airfoils with a high degree of camber that opens, to change camber that opens, to change the airflow’s directionthe airflow’s direction
Chapter 1, Lesson 5Courtesy of Dan Brownlee
Noise SuppressorsNoise Suppressors Laws regulate how much noise an aircraft can Laws regulate how much noise an aircraft can
makemake Flow of exhaust creates much of the racketFlow of exhaust creates much of the racket Chevron noise suppressor has teeth cut in Chevron noise suppressor has teeth cut in
nozzle’s edge to reduce noisenozzle’s edge to reduce noise Corrugated noise suppressor has ridged Corrugated noise suppressor has ridged
nozzles; breaks noise in a large exhaust flownozzles; breaks noise in a large exhaust flow Ejector-type noise suppressor directs Ejector-type noise suppressor directs
surrounding air so it mixes with the high-surrounding air so it mixes with the high-velocity exhaust to reduce noisevelocity exhaust to reduce noise
Chapter 1, Lesson 5Copyright © Boeing. All Rights Reserved
Chapter 1, Lesson 5
Learning Check QuestionsLearning Check Questions
CPS Questions 7-8CPS Questions 7-8
Activity 3: Activity 3: Jet Engine CharacteristicsJet Engine Characteristics
View the various animations of a jet engine View the various animations of a jet engine to observe the parts and their functionsto observe the parts and their functions
Label the parts and provide a short Label the parts and provide a short description of characteristicdescription of characteristic
Chapter 1, Lesson 5
Activity 3: EngineActivity 3: Engine
Chapter 1, Lesson 5 Reproduced from NASA/Glen Research Center
Activity 3: CompressorActivity 3: Compressor
Chapter 1, Lesson 5 Reproduced from NASA/Glen Research Center
Activity 3: TurbineActivity 3: Turbine
Chapter 1, Lesson 5 Reproduced from NASA/Glen Research Center
Reaction EnginesReaction Engines
Reaction engine develops Reaction engine develops thrust by its reaction to a thrust by its reaction to a substance ejected from itsubstance ejected from it
Operates according to Operates according to Newton’s third law of Newton’s third law of motion motion
Rocket engines are also Rocket engines are also reaction enginesreaction engines
Chapter 1, Lesson 5Courtesy of NASA
The Development of The Development of New Engine TechnologyNew Engine Technology
Aerospace engineers are working on new engine Aerospace engineers are working on new engine technologies that cut fuel use and reduce emissionstechnologies that cut fuel use and reduce emissions
Geared turbofan engine reduces fuel consumption, Geared turbofan engine reduces fuel consumption, emissions, engine noise, and operating costsemissions, engine noise, and operating costs
Open rotor jet engine focuses on fuel efficiency, Open rotor jet engine focuses on fuel efficiency, reduced emissions, and noise reductionreduced emissions, and noise reduction
Chapter 1, Lesson 5 Courtesy of NASA/Glenn Research Center
Thrust VectoringThrust Vectoring
Thrust vector engine has nozzles that turn to Thrust vector engine has nozzles that turn to redirect thrust; lets aircraft maneuver with redirect thrust; lets aircraft maneuver with greater precisiongreater precision
The aim of this technology is maneuverability, The aim of this technology is maneuverability, not fuel efficiencynot fuel efficiency
Chapter 1, Lesson 5 Courtesy of NASA/Glenn Research Center
Chapter 1, Lesson 5
Learning Check QuestionsLearning Check Questions
CPS Questions 9-10CPS Questions 9-10
Activity 4: Flight PowerActivity 4: Flight Power
Create a presentation on a jet engine (current Create a presentation on a jet engine (current model or one under development)model or one under development)
Research sources and describe how the Research sources and describe how the engine works, and why the engine is suited for engine works, and why the engine is suited for the aircraft’s purposethe aircraft’s purpose
Chapter 1, Lesson 5
SummarySummary
The principles of Boyle’s Law, Charles’s The principles of Boyle’s Law, Charles’s Law, and Gay-Lussac’s LawLaw, and Gay-Lussac’s Law
The characteristics of internal The characteristics of internal combustion enginescombustion engines
The mechanical, cooling, and ignition The mechanical, cooling, and ignition systems of reciprocating enginessystems of reciprocating engines
Chapter 1, Lesson 5
Summary, cont.Summary, cont.
How the different types of jet engines How the different types of jet engines workwork
The role of reversers and suppressors The role of reversers and suppressors used in jet aircraftused in jet aircraft
Reaction enginesReaction engines The development of new engine The development of new engine
technologytechnology
Chapter 1, Lesson 5
Chapter 1, Lesson 5
Review QuestionsReview Questions
CPS Questions 11-12CPS Questions 11-12
Next….Next….
Done – Done – flight powerflight power
Next – aviation innovationNext – aviation innovation
Chapter 1, Lesson 5 Copyright © Boeing. All Rights Reserved