Powerplant

Question 1

The two major fixed-wing aircraft propulsion systems are?

Answer 1

Propellers or Jets

Question 2

Propeller or prop-driven airplanes, _______

Answer 2

generate thrust by using one or more propellers with two or more slanted blades that work in a corkscrew motion to push the air backwards, and according to Newton’s third law, push itself forward

Question 3

Often, the slant or pitch of propellers can be variable. That is?

Answer 3

the pilot can control the slant to decide much pull or thrust to generate from the propeller

Question 4

There are models that put the propellers in the back, such as the _______

Answer 4

original Wright Brothers 1903 model that had it in the back, hence given the name push prop, but these are in the minority

Question 5

The powerplant of a propeller-driven airplane is usually considered to include _______

Answer 5

both the engine and propeller.

Question 6

In propeller-driven airplanes, the primary function of the engine is to _______

Answer 6

turn the propeller, but it also generates electricity power, a vacuum source for some flight instruments, and a heat source for the pilot and passengers in most small single-engine airplanes

Question 7

Propellers can either be ______

Answer 7

Fixed-pitch or variable-pitch propellers

Question 8

Fixed-pitch propellers have _______

Answer 8

their blades fixed at an angle. These propellers turn directly with the engine crankshaft; the engine turns the crankshaft as well as the propeller, and the propeller turns the engine’s rotary power into thrust.

Question 9

Variable-pitch propellers, also known as _______are the _______

Answer 9

constant-speed propellers

efficient counterpart of fixed-propellers, because the pilot can adjust the blade’s angle for better efficiency

Question 10

Nacelle

Answer 10

nəˈsel

a streamlined housing or tank for something on the outside of an aircraft or motor vehicle.

Question 11

Single-engine propeller-driven airplanes usually have the engine in _______

Answer 11

front of the fuselage, covered by a cowling that streamlines airflow around the engine and ducts air around the engine’s cylinders to cool it off

Question 12

Multiple-engine airplanes, wether propeller-driven or jet, usually have the engines _______

Answer 12

mounted below the wings, covered by nacelles, which perform the same function as cowlings. Some airplanes have them on the empennage, but that’s in the minority.

Question 13

There several variations of jet engines, including _______

Answer 13

turbojet, turbofan, and ramjet

Question 14

All variations of jet engines work _______

Answer 14

under the same principles, but they differ in their distinct advantages and disadvantages

Question 15

What is an afterburner?

Answer 15

An afterburner can be equipped in turbojets and turbofans. It is a tube between the turbine and the rear exhaust nozzle where additional fuel is put to be ignited along with the exhaust for further thrust, but this consumes a lot of fuel, so they can only be used for short periods

Question 16

An ideal gas is a gas made up of what?

Answer 16

An ideal gas is a gas made up of molecules that only collide with each other and its container.

Question 17

Ideal gas formula:

Answer 17

PV = nRT

Question 18

Boyle’s law states what?

Answer 18

Boyle’s law states that pressure and volume are inversely proportional if temperature and amount of material stays the same.

Question 19

Boyle’s law formula:

Answer 19

P1/T1 = P2/T2

Any K

Question 20

Charles law states what?

Answer 20

Charles law states that the volume of a gas is directly proportional to the temperature if pressure and number of moles are constant.

Question 21

Charles law formula:

Answer 21

V1/T1 = V2/T2

Any K

Question 22

Gay-Lussac’s Law states what?

Answer 22

Gay-Lussac’s Law states that pressure is directly proportional to temperature if the volume is constant.

Question 23

Gay-Lussac’s Law formula:

Answer 23

P1/T1 = P2/T2

Any K

Question 24

A reciprocating engine produces power by what?

Answer 24

A reciprocating engine produces power by burning fuel inside cylinders

Question 25

How a reciprocating engine works:

Answer 25

1. The engine starter cranks the engine
2. Camshaft is timed for intake and exhaust openings
3. Intake valves open and let fuel/air mixture into the cyclinder
4. Intake valves closes, and mixture gets compressed
5. The compressed mixture is ignited by the spark plug, driving the piston downward and powering the crankshaft.
6. Exhaust valves open and let the waste gases out.
7. Power strokes repeat

Question 26

All rotary engines and reciprocating engines are what?

Answer 26

All rotary engines and reciprocating engines are types of internal combustion engines

Question 27

A starter (engine) is a what?

Answer 27

A starter (also self-starter, cranking motor, or starter motor) is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine’s operation under its own power. Starters can be electric, pneumatic, or hydraulic.

Question 28

The four stroke cycle:

Answer 28

1. Intake
2. Compression
3. Ignition (Power)
4. Exhaust

Question 29

What do all airplanes require to produce thrust?

Answer 29

All airplanes require a propulsion system to produce thrust

Question 30

Engines turn fuel into what?

Answer 30

Engines turn fuel into heat energy, which is then turned into mechanical energy to generate thrust

Question 31

There are different types of propulsion systems, such as:

Answer 31

reciprocating engines, turbine engines, and electric engines

Question 32

A reciprocating engine produces power by doing what?

Answer 32

A reciprocating engine produces power by burning fuel inside cylinders

Question 33

The crankshaft and connecting rod do what?

Answer 33

The crankshaft and connecting rod, turn the straight piston motion into rotary motion, but the crankshaft is what runs the engine and turns the propeller

Question 34

The crankcase encloses what?

Answer 34

The crankcase encloses the crankshaft

Question 35

There are four main different types of arrangements used to classify reciprocating engines:

Answer 35

Inline engines, V-type engines, Opposed or O-type engines, and Radial engines

Question 36

Inline engines:

Answer 36

Inline engines are found in very old light aircraft, and they don’t produce a lot of horsepower. They have an even number of cylinders in one line, attached to one crankshaft, and can be air or liquid cooled.

Question 37

V-type engines:

Answer 37

V-type engines are commonly found on motorcycles. Their basic design is two inline engines joined by a v-shape, which have a common crankshaft and can be air or liquid cooled.

Question 38

O-type or opposite type engines:

Answer 38

O-type or opposite type engines have two banks of cylinders opposite to each other, and the crankshaft in the middle. These can be air or liquid cooled, and are mainly found in light general aviation aircraft, such as the Cessna 172 and Piper Cherokee

Question 39

Radial engines:

Answer 39

Radial engines have a circular row of cylinders with the crankshaft in the center. This arrangement allows for efficient airflow cooling, and has a better power to weight ratio than the other designs. Many still exist today, but their use is limited. Many older cargo aircraft still use the radial engine. They were common in WW2 aircraft, such as the Boeing B-29

Question 40

The gas turbine engine is the preferred type of engine because?

Answer 40

The gas turbine engine is the preferred type of engine because it offers a tremendous amount of thrust to fly faster

Question 41

There are four main types of gas turbine engines:

Answer 41

turbojet, turboprop, turbofan, and turboshaft.

Question 42

All gas turbine engines have similar components:

Answer 42

air inlet, compressor, combustion section, turbine, and nozzle. Also, the cold section and the hot section

Question 43

At high speeds, the air intake section keeps the airflow under what speeds?

Answer 43

At high speeds, the air intake section keeps the airflow under Mach 1 speeds, which is essential for all aircraft no matter how fast they fly.

Question 44

Turboprop engine:

Answer 44

the turboprop engine is a form of the turbojet engine, but it is connected to a propeller. In the engine, the turbine is connected to a shaft, and the shaft connected to a gearbox. The gearbox slows the spinning and allows the propeller to spin. The propeller’s spinning motion produces thrust.

Question 45

The main advantage and some disadvantages of turboprop engines are what?

Answer 45

The main advantage of turboprop engines is that they are more fuel efficient than turbojet engines. Some disadvantages are that it limits forward airspeed, and that the gear system is heavy and prone to break down.

Question 46

Turboprop engines are most efficient between what speeds and altitudes?

Answer 46

Turboprop engines are most efficient between 200 to 450 knots and 18,000 to 30,000 feet of altitude.