cessna system
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Aircraft SystemsAircraft Systems
Presented by:Presented by:
Carol Cushman & Kyle Carol Cushman & Kyle BlackBlack
Engine TypesEngine Types
Turbine EngineTurbine Engine– Found in transport Category aircraftFound in transport Category aircraft– Relatively costly but extremely Relatively costly but extremely
powerfulpowerful Reciprocating EngineReciprocating Engine
– Found in general aviationFound in general aviation– Economical, but still very reliable Economical, but still very reliable
Cessna EngineCessna Engine
Horizontally Horizontally OpposedOpposed
Direct DriveDirect Drive Air CooledAir Cooled 4 cylinder4 cylinder
Engine OperationEngine Operation
What are the four strokes of an What are the four strokes of an engine?engine?
Four Strokes on an Four Strokes on an EngineEngine
IntakeIntake
When the piston moves away When the piston moves away form the cylinder headform the cylinder head
Intake valve opensIntake valve opens Fuel/Air mixture is drawn into the Fuel/Air mixture is drawn into the
combustion chambercombustion chamber
CompressionCompression
Piston moves back toward the Piston moves back toward the cylinder headcylinder head
Intake valve closesIntake valve closes Fuel/Air Mixture is compressedFuel/Air Mixture is compressed
PowerPower
Compression nearly completeCompression nearly complete Spark plugs fireSpark plugs fire Compressed mixture is ignitedCompressed mixture is ignited Rapidly expanding gases drive Rapidly expanding gases drive
the piston, providing the power the piston, providing the power that rotates the crankshaftthat rotates the crankshaft
ExhaustExhaust
Expels the burned gases through Expels the burned gases through the exhaust valve, which opens at the exhaust valve, which opens at the end of the power strokethe end of the power stroke
Induction SystemInduction System
Brings outside air into the engine, Brings outside air into the engine, mixes it with fuel in the proper mixes it with fuel in the proper proportion and deliver it to the proportion and deliver it to the cylinders where combustion cylinders where combustion occurs.occurs.
ThrottleThrottle MixtureMixture Intake PortIntake Port
ThrottleThrottle
Controls Engine SpeedControls Engine Speed Regulates the amount of fuel/air Regulates the amount of fuel/air
mixture that flows into the mixture that flows into the cylinderscylinders
MixtureMixture
Controls the fuel/air ratioControls the fuel/air ratio
Intake PortIntake Port
Where outside air enters the Where outside air enters the induction systeminduction system
Normally contains an air filter to Normally contains an air filter to keep out dust and FODkeep out dust and FOD
Carburetor Carburetor
Mixes the incoming air with fuel Mixes the incoming air with fuel and delivers it to the combustion and delivers it to the combustion chamberchamber
CarburetorCarburetor
Air passes through a venturi, increases Air passes through a venturi, increases velocity and decreases pressurevelocity and decreases pressure
Fuel enters from a float chamber Fuel enters from a float chamber where it is maintained at a nearly where it is maintained at a nearly constant level by a float deviceconstant level by a float device
Discharge nozzle is located in an area Discharge nozzle is located in an area of low pressure created by the venturiof low pressure created by the venturi
Fuel is forced through the discharge Fuel is forced through the discharge nozzel by the higher atmospheric nozzel by the higher atmospheric pressure in the float chamberpressure in the float chamber
Overly Rich MixtureOverly Rich Mixture
What does it mean to have a What does it mean to have a “Rich” mixture?“Rich” mixture?– As altitude increases, the mixture will As altitude increases, the mixture will
get progressively richer due to the get progressively richer due to the decrease in air density.decrease in air density.
– Can result in engine roughness: Can result in engine roughness: excessive carbon buildup on the excessive carbon buildup on the spark plug will cause them to foul.spark plug will cause them to foul.
– High elevation airports, climb or High elevation airports, climb or cruise at high elevationcruise at high elevation
Overly Lean MixtureOverly Lean Mixture
What does it mean to have a What does it mean to have a “Lean” mixture?“Lean” mixture?– May result in high engine May result in high engine
temperatures causing excessive temperatures causing excessive wear or even failurewear or even failure
– Enrichen Mixture on descents from Enrichen Mixture on descents from high altitudeshigh altitudes
– Watch engine temperatureWatch engine temperature
Carburetor IceCarburetor Ice
Occurs due to the effect of fuel Occurs due to the effect of fuel vaporization and decreasing pressure vaporization and decreasing pressure in the venturi which causes a sharp in the venturi which causes a sharp temperature drop in the carburetortemperature drop in the carburetor
If water vapor in the air condenses If water vapor in the air condenses when the carburetor temperature is at when the carburetor temperature is at or below freezing, ice may form on or below freezing, ice may form on internal surfaces of the carburetor, internal surfaces of the carburetor, including the throttle valveincluding the throttle valve
Likely below 21C (70F), humidity Likely below 21C (70F), humidity above 80% above 80%
Carburetor IceCarburetor Ice
Carburetor IceCarburetor Ice
Carburetor Ice Carburetor Ice IndicationsIndications Why can Carburetor Ice be dangerous?Why can Carburetor Ice be dangerous? What are some indications of Carb Ice?What are some indications of Carb Ice?
– Drop in engine RPMDrop in engine RPM– Engine RoughnessEngine Roughness– Fuel starvationFuel starvation
What can we do to get rid of What can we do to get rid of carburetor ice or even prevent it from carburetor ice or even prevent it from happening in the first place?happening in the first place?– Carburetor HeatCarburetor Heat
Carburetor HeatCarburetor Heat
Carburetor ice is especially dangerous when Carburetor ice is especially dangerous when operating at low power settings, may go operating at low power settings, may go unnoticed until power is addedunnoticed until power is added
How does carburetor heat work?How does carburetor heat work?– Carburetor heat routes air across a heat source before Carburetor heat routes air across a heat source before
it enters the carburetorit enters the carburetor
How will carb heat affect engine performance?How will carb heat affect engine performance?– Causes a slight decrease in engine power (heated air is Causes a slight decrease in engine power (heated air is
less dense)less dense)– If ice is present, there will be a decrease followed by a If ice is present, there will be a decrease followed by a
gradual increase in rpmgradual increase in rpm
Carburetor HeatCarburetor Heat
Fuel InjectionFuel Injection
What is the benefit of a fuel What is the benefit of a fuel injected fuel system?injected fuel system?– No carburetorNo carburetor– More precision in metering and More precision in metering and
distributing fuel/air mixturedistributing fuel/air mixture– Injects the fuel directly into each Injects the fuel directly into each
cylinder separatelycylinder separately– Lower fuel consumption, increased Lower fuel consumption, increased
Horsepower, lower operating Horsepower, lower operating temperatures, longer engine lifetemperatures, longer engine life
Fuel InjectionFuel Injection
High Altitude FlightHigh Altitude Flight
SuperchargerSupercharger– Compresses the incoming air to the Compresses the incoming air to the
engine using a pump driven by the engine using a pump driven by the engineengine
TurbochargerTurbocharger– Pressurizes the air into the engine Pressurizes the air into the engine
using a mechanism driven by using a mechanism driven by exhaust gasesexhaust gases
TurbochargerTurbocharger
Ignition SystemIgnition System
What does the ignition system do?What does the ignition system do?– Provides spark that ignites the fuel/air Provides spark that ignites the fuel/air
mixture in the cylindersmixture in the cylinders List the parts of the ignition system.List the parts of the ignition system.
– MagnetosMagnetos– Spark PlugsSpark Plugs– Interconnecting wires Interconnecting wires – Ignition SwitchIgnition Switch
MagnetoMagneto
What is a Magneto?What is a Magneto?– Self contained, Engine drivenSelf contained, Engine driven– Supplies electrical current to the spark plugsSupplies electrical current to the spark plugs– Uses permanent magnet for electrical current Uses permanent magnet for electrical current
that is completely separate from the electrical that is completely separate from the electrical systemsystem
– Begins when you engage starter Begins when you engage starter – Operates whenever the crankshaft turnsOperates whenever the crankshaft turns– Normally two for redundancy/ improves Normally two for redundancy/ improves
combustioncombustion If you lose your battery/alternator in flight, If you lose your battery/alternator in flight,
will your engine stop working?will your engine stop working?
MagnetoMagneto
Ignition SwitchIgnition Switch
Controls the operation of the magneto Controls the operation of the magneto from the cockpitfrom the cockpit
Can select left, right or bothCan select left, right or both Engine can still fire even with the Engine can still fire even with the
battery and master switches off, if the battery and master switches off, if the magnetos are left on and the prop is magnetos are left on and the prop is moved because no outside electrical moved because no outside electrical power is requiredpower is required
Abnormal CombustionAbnormal Combustion
Name two types of Abnormal Name two types of Abnormal Combustion:Combustion:
– DetonationDetonation– Pre-ignitionPre-ignition
DetonationDetonation
What is Detonation?What is Detonation?– Explosive ignition of the fuel/air mixture Explosive ignition of the fuel/air mixture
within the cylinders combustion chamber within the cylinders combustion chamber – UncontrolledUncontrolled– Engine overheating, roughness or loss of Engine overheating, roughness or loss of
powerpower– Excessive temperatures and pressures Excessive temperatures and pressures
leading to failure of piston, cylinder or leading to failure of piston, cylinder or valvesvalves
– Engine overheat or lower than Engine overheat or lower than recommended fuel graderecommended fuel grade
Pre-IgnitionPre-Ignition
What is Pre-Ignition?What is Pre-Ignition?– Fuel/Air mixture is ignited in advance of Fuel/Air mixture is ignited in advance of
the normal timed ignitionthe normal timed ignition– Detonation can lead to pre – ignitionDetonation can lead to pre – ignition– Caused by a residual hot spot in the Caused by a residual hot spot in the
cylinder such as a small carbon deposit on cylinder such as a small carbon deposit on a spark plug , cracked ceramic spark plug a spark plug , cracked ceramic spark plug insulator, or any damage around the insulator, or any damage around the combustion chambercombustion chamber
Fuel SystemFuel System
What are the two different types What are the two different types of fuel systems found on small of fuel systems found on small airplanes?airplanes?
1. Fuel-Pump System1. Fuel-Pump System
2. Gravity Feed2. Gravity Feed
Fuel-Pump SystemFuel-Pump System
Engine Driven Engine Driven PumpPump
Electric Fuel pumpElectric Fuel pump Provides fuel under Provides fuel under
pressure from the pressure from the fuel tanks to the fuel tanks to the engineengine
Low wing airplanesLow wing airplanes
Fuel-Pump SystemFuel-Pump System
Fuel Pressure GaugeFuel Pressure Gauge– Gives and exact reading of the Gives and exact reading of the
pressure the fuel pump is providing pressure the fuel pump is providing the enginethe engine
– Helpful in detecting fuel pump Helpful in detecting fuel pump malfunctionsmalfunctions
Fuel-Pump System Fuel-Pump System
What is Vapor Lock?What is Vapor Lock?– When the fuel in the lines of a fuel When the fuel in the lines of a fuel
injected engine vaporizes due to injected engine vaporizes due to excessive heat, and prevents the excessive heat, and prevents the flow of fuel to the engineflow of fuel to the engine
– Common on a hot day in fuel Common on a hot day in fuel injected aircraftinjected aircraft
Gravity – Feed SystemGravity – Feed System
Fuel flows to the engine by Fuel flows to the engine by gravity from the fuel tanksgravity from the fuel tanks
High wing aircraftHigh wing aircraft
PrimerPrimer
What do we use a primer for?What do we use a primer for?– Used to pump fuel directly into the Used to pump fuel directly into the
intake system prior to engine startintake system prior to engine start– Useful in cold weather when fuel in the Useful in cold weather when fuel in the
carburetor is difficult to vaporizecarburetor is difficult to vaporize How do you prime a carbureted How do you prime a carbureted
engine?engine? How does this process differ in a fuel How does this process differ in a fuel
injected engine?injected engine?
Fuel TanksFuel Tanks
Where are the fuel tanks in most Where are the fuel tanks in most aircraft?aircraft?– Usually located in the wingsUsually located in the wings– Vented to allow for changes in Vented to allow for changes in
pressure inside the tank, prevents pressure inside the tank, prevents vacuum vacuum
Fuel Quantity GaugesFuel Quantity Gauges
Located on the instrument panelLocated on the instrument panel Shows the amount of fuel in each Shows the amount of fuel in each
fuel tankfuel tank
Fuel Selector ValveFuel Selector Valve
Allows you to select fuel from Allows you to select fuel from various tanksvarious tanks
Some may only have Left, Right Some may only have Left, Right and OFF – must monitorand OFF – must monitor
Fuel StrainerFuel Strainer
What is the Fuel Strainer use for?What is the Fuel Strainer use for?– Removes moisture and other sediments Removes moisture and other sediments
that might be in the systemthat might be in the system– In cold weather, moisture is hazardous In cold weather, moisture is hazardous
because it can freeze and block fuel linesbecause it can freeze and block fuel lines– In warm weather, it can flow into the In warm weather, it can flow into the
carburetor and stop the enginecarburetor and stop the engine Tanks should be filled each evening to Tanks should be filled each evening to
prevent condensationprevent condensation
Re- FuelingRe- Fueling
Red: 80/87 octaneRed: 80/87 octane Green: 100/130Green: 100/130 Blue: 100LLBlue: 100LL Clear: JetClear: Jet In emergency, always use next In emergency, always use next
higher grade (but never jet)higher grade (but never jet)
Oil SystemOil System
What are some functions of oil in What are some functions of oil in a reciprocating engine?a reciprocating engine?– LubricatesLubricates– CleansCleans– SealsSeals– Cools Cools – ProtectsProtects
Dry- Sump SystemDry- Sump System
Oil is contained in a separate tankOil is contained in a separate tank Circulated through the engine by Circulated through the engine by
pumpspumps
Wet Sump SystemWet Sump System
Oil is carried in a sumpOil is carried in a sump Integral part of the engineIntegral part of the engine Found on most small general Found on most small general
aviation aircraftaviation aircraft
Wet Sump Oil SystemWet Sump Oil System
Oil Pressure GaugeOil Pressure Gauge
Provides direct indication of the oil Provides direct indication of the oil system operationsystem operation
Below normal pressure may mean that Below normal pressure may mean that the oil pump is not putting out enough the oil pump is not putting out enough pressure to circulate oil throughout the pressure to circulate oil throughout the engine. engine.
Above normal may indicate a clogged Above normal may indicate a clogged oil lineoil line
Shut down engine if oil pressure does Shut down engine if oil pressure does not begin to rise within 30 seconds for not begin to rise within 30 seconds for warm starts/60 seconds cold startswarm starts/60 seconds cold starts
Oil Temperature GaugeOil Temperature Gauge
Measures temperature of the oil Measures temperature of the oil as it enters the engineas it enters the engine
Slow changesSlow changes
Cooling SystemsCooling Systems
Excessively high engine temperatures Excessively high engine temperatures can result in a loss of power, high oil can result in a loss of power, high oil consumption and engine damage.consumption and engine damage.
Internal cooling is done by oil, but Internal cooling is done by oil, but more is needed to maintain normal more is needed to maintain normal temperaturestemperatures
Remaining heat dissipated by exhaust Remaining heat dissipated by exhaust and through outside air flowing around and through outside air flowing around the enginethe engine
Cowl FlapsCowl Flaps
Create a large path for air to Create a large path for air to escape from the engine escape from the engine compartmentcompartment
Flaps that open on the bottom of Flaps that open on the bottom of the engine cowlingthe engine cowling
Increases cooling air flowIncreases cooling air flow
Cowl FlapsCowl Flaps
Cylinder Head Cylinder Head Temperature GaugeTemperature Gauge Usually in airplanes with Cowl Usually in airplanes with Cowl
FlapsFlaps Direct temperature reading from Direct temperature reading from
one of the cylindersone of the cylinders Reducing Engine TemperaturesReducing Engine Temperatures
– Enrichen mixtureEnrichen mixture– Reduce rate of climbReduce rate of climb– Increase airspeedIncrease airspeed– Decrease power settingDecrease power setting
Exhaust SystemExhaust System
Vent burned gasesVent burned gases Provide heat for cabinProvide heat for cabin Directs exhaust out below the engine Directs exhaust out below the engine
compartment through a muffler and compartment through a muffler and tailpipe tailpipe
As the hot exhaust gases heat the As the hot exhaust gases heat the muffler, metal shrouds around the muffler, metal shrouds around the muffler capture the heat and duct it to muffler capture the heat and duct it to the cabin. the cabin.
PropellersPropellers
Provides thrust to propel the Provides thrust to propel the airplane through the air.airplane through the air.
Each blade is an airfoil that acts Each blade is an airfoil that acts like a rotating winglike a rotating wing
Amount of thrust produced is a Amount of thrust produced is a function of shape, rotation speed function of shape, rotation speed and position relative to the and position relative to the relative windrelative wind
PropellersPropellers
Each small section of blade is set Each small section of blade is set at a different angle to the plane at a different angle to the plane of rotationof rotation
Gradual decrease in blade angle Gradual decrease in blade angle gives twisted appearancegives twisted appearance
Allows the propeller to provide Allows the propeller to provide more uniform thrust throughout more uniform thrust throughout most of the length of the blademost of the length of the blade
PropellersPropellers
Climb PropellerClimb Propeller
Low blade angleLow blade angle Best performance for takeoff and Best performance for takeoff and
climbclimb
Cruise PropellerCruise Propeller
High blade angleHigh blade angle High speed cruiseHigh speed cruise High altitude flightHigh altitude flight
Fixed – Pitch PropellerFixed – Pitch Propeller
Blade angle is selected on the Blade angle is selected on the basis of what is best for the basis of what is best for the primary function of the airplaneprimary function of the airplane
Cannot be changed by the pilotCannot be changed by the pilot
Constant Speed Constant Speed PropellerPropeller Pilot can adjust the blade angle Pilot can adjust the blade angle
for the most efficient operationfor the most efficient operation
Electrical SystemElectrical System
Electrical System Electrical System DefinitionsDefinitions Amp: flow rateAmp: flow rate Volt: measure of electromagnetic Volt: measure of electromagnetic
force. Volts are pressure that force. Volts are pressure that push amps to give powerpush amps to give power
Volts X Amps = WattsVolts X Amps = Watts
Alternators v. Alternators v. GeneratorsGenerators AlternatorsAlternators
– Produces sufficient Produces sufficient amount of electrical amount of electrical current at slower RPM current at slower RPM by producing AC by producing AC current that is current that is converted to DCconverted to DC
– More constant at More constant at different ranges of different ranges of engine speedsengine speeds
– Lighter weightLighter weight– Less costly to maintainLess costly to maintain– Less prone to Less prone to
overloadingoverloading
GeneratorsGenerators– Do not produce Do not produce
enough electrical enough electrical current at low engine current at low engine RPM to operate RPM to operate entire electrical entire electrical system.system.
– Electrical needs often Electrical needs often rely on battery, rely on battery, which is quickly which is quickly depleteddepleted
AlternatorAlternator
Engine DrivenEngine Driven Supplies engine when running Supplies engine when running
with electrical supplywith electrical supply Usually 14-28 voltUsually 14-28 volt
Alternating Current Alternating Current (AC)(AC) Type of current produced by an Type of current produced by an
alternatoralternator Current that changes directionCurrent that changes direction
Direct Current (DC)Direct Current (DC)
Current that flows in one directionCurrent that flows in one direction Aircraft run off of direct currentAircraft run off of direct current AC must be converted to DCAC must be converted to DC Battery is DC currentBattery is DC current
BatteryBattery
Main purpose is to provide a Main purpose is to provide a means of starting the enginemeans of starting the engine
Limited operation of electrical Limited operation of electrical components (Clock, hourmeters)components (Clock, hourmeters)
Source of standby or emergency Source of standby or emergency electrical power in case of electrical power in case of alternator malfunctionalternator malfunction
AmmeterAmmeter
Used to monitor the electrical current Used to monitor the electrical current in amperes within the systemin amperes within the system
Positive value means battery is being Positive value means battery is being chargedcharged
Negative value means you are drawing Negative value means you are drawing off of the batteryoff of the battery
Two typesTwo types– One reflects current flowing to or from the One reflects current flowing to or from the
batterybattery– Other type displays the load placed on the Other type displays the load placed on the
alternator and is often called a loadmeteralternator and is often called a loadmeter
AmmeterAmmeter
Two Types:Two Types:– One reflects current flowing to or One reflects current flowing to or
from the batteryfrom the battery– One displays the load placed on the One displays the load placed on the
alternator and is often called a load alternator and is often called a load metermeter
Master SwitchMaster Switch
Controls the entire electrical Controls the entire electrical systemsystem– Except battery and magnetosExcept battery and magnetos
Battery and Alternator SwitchesBattery and Alternator Switches– Similar to MasterSimilar to Master– You can turn of the Alternator in the You can turn of the Alternator in the
event of failure, at which point all event of failure, at which point all current will be drawn the battery. At current will be drawn the battery. At that point, you will need to load shedthat point, you will need to load shed
Circuit Breakers/FusesCircuit Breakers/Fuses
Protect various components from Protect various components from overloadsoverloads
Resetting a breaker will usually Resetting a breaker will usually re-activate the circuitre-activate the circuit
In the event of an alternator In the event of an alternator failure, you may have to reduce failure, you may have to reduce the load on the battery by pulling the load on the battery by pulling certain non – essential circuit certain non – essential circuit breakers.breakers.
Circuit BreakersCircuit Breakers
Bus BarsBus Bars
Tie Bus
Avionics (40) Non – Essential (40)l Main Bus (60)
AP Com. 1 Rec. lts Heater Strobe Pitot
Voltage Regulator Voltage Regulator
Controls the rate of charge to the Controls the rate of charge to the battery by stabilizing battery by stabilizing generator/alternator electrical generator/alternator electrical output.output.
Alternator voltage is normally Alternator voltage is normally slightly higher than battery slightly higher than battery (otherwise, the battery would be (otherwise, the battery would be charging the alternator)charging the alternator)
Overvoltage RelayOvervoltage Relay
Located in alternatorLocated in alternator Takes the alternator offline if the Takes the alternator offline if the
output exceeds a predetermined output exceeds a predetermined valuevalue
QuestionsQuestions
Any questions?Any questions?
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