YOUTUBE Flashcards
An aircraft engine classified as?
Heat Engine
1 BTU = ?
778 ft. lbs of work
33,000 ft lbs / min = ?
1 Horse Power (H.P.)
12 gal fuel burned / hr = ?
565 Horse Power
Aircraft Engine:
12 gal fuel burned / hr = ?
130 HP at 24% effieciency
Number of lbs fuel burned / hr to produce 1 brake HP = ?
Brake Specific Fuel Consumption / BSFC
determines the efficiency of engine operation.
Proper Fuel Metering
used to monitor engine behavior in flight.
Aircraft Instruments
What are the aircraft instruments:
Tachometer
Manifold Pressure Gauge
Exhaust Gas Temperature Indicator
provides an indication of the number of power strokes the engine is producing each minute.
Tachometer
indicates the pressure of the air forcing the combustible charge into the cylinders.
Manifold Pressure Gauge
lower the air density.
Altitude and High Humidity
Some of the power lost of this decrease in air density maybe regained simply by using a (?) to compress to the air before it enters the engine.
SUPERCHARGER
cause a light power loss from the back pressures created from the turbine.
TURBOCHARGERS
is determined by thr air presaure and compression ratio.
Final Pressure w/in Cylinder
increases efficiency and power.
HIGHER PRESSURE
When the critical pressure and temperature of fuel is reached, the fuel released its remaining energy instantaneously explodind rather than burning evenly, this explosion is called (?).
DETONATION
Detonation prevented by:
- Maintaining proper Manifold Pressure and RPM relationship
- Rich Fuel-Air Mixture
is a special blend of hydrocarbon fuel that contains additives to inhibits corrosion, improver storage capability, increase resistance into detonation.
AVIATION GASOLINE
OR AVGAS
A (?) added to the fuel to identify its anti detonation rating.
DYE
3 Grades of Aviation Gasoline
GRADE 80 - RED
GRADE 100 - GREEN
LOW LEAD 100 - BLUE
The difference is this fuels primarily the amount of the additive (?) which is used to suppress the detonation.
TETRAETHYL LEAD
has a maximum of 1/2 mL of te L/gal and is dyed red.
GRADE 80
is used for engines with low compression ratios and low power grade.
GRADE 80 FUEL
ia dyed green with as much as 4.6 mL of te L/gal added.
GRADE 100 FUEL
-for use in higher powered engines.
-high compression ratios.
GRADE 100 FUEL
a comprised fuel with the same anti detonation rating as the grade 100 but with only 2ml of te L/gal.
LOW LED-100 FUEL
is dyed blue.
LOW LED-100 FUEL
Never use fuel with a (?) than that approved for the engine.
LOWER RATING
is increased by the use of more tetraethyl lead, if a fuel is used with a higher octane rating than is approved for the engine there is posiibility that the extra led will foul the spark plugs.
ANTI DETONATION RATING OR OCTANE NUMBER OF A FUEL
it is used to help scavenge lead deposits left from Te L, this converts led oxides into volatile lead bromides that are scavenged with exhaust gases
ETHYLENE DIBROMIDE
It is a pressure of the air aboce the fuel that is needed to hold the vapors in liquid form or to keep it from boiling off.
VAPOR PRESSURE
Aviation gasoline vapor pressure cannot exceed (?) lbs/in2.
7 lbs/in2
is a major concern to a every aviation technician.
FUEL CONTAMINATION
needed to prevent watee rust or dirt from reaching the aircraft fuel system from storage tanks.
FILTERS AND FUEL TANKERS
Sufficient fuel must be drained from all aircraft (?) to be sure there is no water in the tanks.
tank sums and strainers
When fueling an aircraft be sure the (?) has not picked up any dirt that can be transferred to the airplane.
nozzle
One of the main secrets of successful fueling is to (?).
keep the fuel clean.
(?) commonly used in our modern lower powered aircraft engine.
FLOAT CARBURATOR
the heart of carburator
VENTURI
this specially shaped restrictor located in the air iblet to the engine speeds up the air as it passed through as tye velocity increases the pressure of the most narrow point deacreases.
VENTURI
this narrow point of the venturi.
causes amount of fuel flowing through the metering jet to be determined by the difference in pressure between the float ball and in pressure nozzle.
Fuel Discharger Nozzle
To control the amount of air flowing into the engine a (?) is installed in the air passage immeadiately after venturi.
disc type butterfly valve
this valve is actuated by the throttle control located in the cockpit.
disc type butterfly valve
To limit the fuel flow in any one position of the throttle valve ghe main metering jet uses an (?).
Orifice
(?) which introduces a measured amount of air into the stream of fuel between the main metering jet and the discharger nozzle.
Main Air Blade
This is used to break up the liquid fu into tiny bubbles so it will fully vaporize as it mixes with the induction air.
Main Air Blade
To control the correct amount of air entering the idling fuel just aftwr it passes through the idle jet an (?).
Idle Air Blade
is used this allows the proper mixture of air and fuel to be drawn up through the emulsion tube and discharged in the air through the idle discharge.
Idle Air Blade
Two separate systems for float carburators:
Idling System
Cruise System
(?) is determined by the # of lbs of fuel and air that are burned in its cylinders.
Power of an Aircraft
Only (?) can be followed in detail uaing only approved replacement parts specified in the service manuals.
manufacturers
The final part of any aircraft maintenance is an entry of the work performed in the (?).
Aircraft Maintenance Records
2 Types of Carburetors
Float-Type Carburetors
Pressure-Type Caburetors
- measures amount of air.
- meters proper amount of fuel.
- maintains mixture ratios.
-enriches the mixture.
FUEL METERING SYSTEM
Both (1) and (2) minimize icing and improve mixture distribution.
- Pressure Carburetors
- Fuel Injection Systems
is a closed fuel metering system with no point open to the atmosphere between the tank and the discharge nozzle.
Pressure Carburetor
Fuel is drawn from the tank pressurized by a (?) metered by the carburetor and sprayed into the induction air.
pump
Both act on a diaphragm to cause it to open a poppet valve.
Venturi Pressure
Impact Pressure
When it becomes necessary to lean the mixture the (?) is merely pulled out, this pulls on a tapered needle located in a passage between the two sidws of the diaphragm.
Manual Mixture Control
Types of Pressure Carburetors:
Manual Mixture Control
Automatic Mixture Control
(?) employs a reverse tapered needlw valve operated by an evacuated bellows as the air density decreases these bellows expand to force the needlw to open the passage between the two chambers and automatically maintain the fuel air mixture ratio set by the pilot.
Automatic Mixture Control
(?) is used to force additional fuel through the discharge nozzle.
Acceleration Pump
it sucks the fuel to booster pump through the engine.
Low Pressure Pump
it pushes the fuel through the engine.
Booster Pump
pump that drive by the engine or in the oxiliary box.
Engine-Driven Pump
the second type of metering is a (?) this uses a step-cut idle valve when the throttle is in the idle position this valve is almost closed by the larger taper on the needle during cruise the crews step of the needle restricts the flow but for full power this needle is completely withdrawn from the orifice creating an opening larger than the main metering jet which will do the actual metering.
manual power enrichment system
(?) improves fuel/air mixture distribution.
Fuel Injection Systems
(?) is designed to limit the amount of air flowing into the engine this slows the engine rpm to idle at the same time the length of the connector between the air vaive and the fuel valve controls the amount of fuel that can flow providing the proper mixture for idling.
Throttle Air Valve Stop
(?) WILL INDICATE AN INCREASE OF FLOW.
CLOGGED INJECTOR NOZZLE
(?) to measure the difference in pressure between the metered fuel and discharged air pressure.
Differential Pressure Gauge
the main benefit of fuel injection systems over (?) is that they provide a uniform mixture distribution .
carburetors
(?) high pump discharge pressure.
SMALL ORIFICE
(?) low pump discharge pressure.
LARGE ORIFICE
