Reciprocating Engine Theory 2

Question 1

The recommended maximum number of hours that an engine can run between overhauls.

Answer 1

Time between overhauls.

TBO

Question 2

The ratio of the weight of an aircraft engine to the brake horsepower it develops.

Answer 2

Specific weight.

Question 3

NASA

Answer 3

National Aeronautics and space administration.

Question 4

NACA

Answer 4

National advisory committee for aeronautics.

Question 5

This assures a good flow of cooling air over the engine cylinders and produces a forward aerodynamic force.

Answer 5

NACA cowling

Question 6

T/F

NACA cowlings actually produce a forward aerodynamic force.

Answer 6

True

Question 7

The ability of an engine to perform as the manufacturer has promised is known as the _______ of an engine.

Answer 7

Reliability.

Question 8

The durability of an aircraft engine may be indicated by the manufacturer’s recommended _______.

Answer 8

TBO

Question 9

A reciprocating engine with all the cylinders arranged in a straight line.

Answer 9

In-line engine.

Question 10

A form of reciprocating engine in which the cylinders are arranged in two banks which are separated by an angle between 45 and 90 degrees.

Answer 10

V-engine

Question 11

An in-line or v-engine in which the cylinders are mounted below the crankshaft.

Answer 11

Inverted engine.

Question 12

A radial engine in which the propeller, crankcase and cylinders revolve as a unit.

Answer 12

Rotary radial engine.

Question 13

The end of a reciprocating engine on which many of the accessories are mounted.

Answer 13

Accessory end.

Question 14

The end of a reciprocating engine to which the propeller mounts.

Answer 14

Propeller end.

Question 15

The end of a reciprocating engine that does not attach to the propeller.

Answer 15

Antipropeller end.

Question 16

T/F

All radial engines number the cylinders with the bottom cylinder as 1.

Answer 16

False.

Top cylinder is 1

Question 17

T/F

Radial engine cylinder numbering progresses consecutively around the engine in a counterclockwise direction.

Answer 17

False.

Direction of the crankshaft

Question 18

A reciprocating engine in which the cylinders are arranged like the spokes of a wheel radiating out from a small central crankcase

Answer 18

Radial engine.

Question 19

The firing order of a nine-cylinder radial engine is _______.

Answer 19

1-3-5-7-9-2-4-6-8

Question 20

The smoothness with which a reciprocating engine runs is determined by the ______.

Answer 20

Spacing and timing of the firing impulses.

Question 21

T/F

All cylinders fire in two revolutions of crankshaft rotation.

Answer 21

True.

Question 22

The reservoir on an aircraft engine that holds the lubrication oil.

Answer 22

Sump.

Question 23

Two basic types of lubrication systems used on aircraft reciprocating engines.

Answer 23

Wet sump.

Dry sump.

Question 24

________ lubrication systems are normally used by radial engines and inverted in-line and V-engines.

Answer 24

Dry-sump

Question 25

_______ engines carry all the lubricating oil in an integral sump that is part of the crankcase.

Answer 25

Wet-sump

Question 26

R =

Answer 26

Radial

Question 27

O =

Answer 27

Opposed

Question 28

A=

Answer 28

Aerobatic

Question 29

G=

Answer 29

Geared nose section

Question 30

H=

Answer 30

Horizontal, for helicopter

Question 31

I=

Answer 31

Fuel injected

Question 32

L (At beginning of sequence) =

Answer 32

Left hand engine rotation

Question 33

L (At end of sequence)

Answer 33

Liquid cooled

Question 34

S=

Answer 34

Supercharged

Question 35

T or TS =

Answer 35

Turbocharged

Question 36

V=

Answer 36

Vertical for helicopter

Question 37

F=

Answer 37

FADEC controlled

Question 38

The middle number in a reciprocating engine ID represents _________.

Answer 38

Piston displacement in cubic inches.

Question 39

Cylinder walls are hardened by either _______ or _______.

Answer 39

Chrome plating, | The process of nitriding.

Question 40

_______ have a surface with a spiderweb of tiny stress cracks.

Answer 40

Channel-chromed cylinders

Question 41

A method of case hardening steel using heat and ammonia gases.

Answer 41

Nitriding.

Question 42

Used to restore or reinforce threads of a bolt hole.

Answer 42

Heli-coil insert

Question 43

The internally threaded, cast aluminum top that is screwed onto the steel cylinder barrel.

Answer 43

Cylinder head.

Question 44

T-shaped valve with a circular head, used to cover the intake and exhaust openings in the cylinder head

Answer 44

Poppet valve

Question 45

Pivoted arm that forces poppet valves off their seats.

Answer 45

Rocker arm.

Question 46

Take more punishment than any other component in an engine.

Answer 46

Exhaust valves.

Question 47

Two or more springs are used on each valve to prevent _____.

Answer 47

Valve surge/float.

Question 48

Multiple springs are used in valves to prevent valve float caused by _______.

Answer 48

Resonant frequency of the spring.

Question 49

______maintain zero clearance in the valve operating train

Answer 49

Hydraulic valve lifters

Question 50

5 reciprocating engine traits:

Answer 50

``` Reliability, Operating flexibility, Durability, Specific weight, Streamline-ability ```

Question 51

Cylinder finish type identified by blue paint.

Answer 51

Nitride

Question 52

Cylinder finish type identified by orange paint.

Answer 52

Chrome plated

Question 53

T/F | The intake valve head is bigger than that of the exhaust valve.

Answer 53

True.

Question 54

T/F | The intake valve stem is bigger than that of the exhaust.

Answer 54

False

Question 55

Some valve stems are filled with sodium to _______.

Answer 55

Dissipate heat.

Question 56

4 types of reciprocating engines:

Answer 56

Radial, Horizontally opposed, V-engine, In-line

Question 57

Two types of cooling:

Answer 57

Air and liquid

Question 58

The purpose of the cylinders’ firing order is to ______.

Answer 58

Reduce vibration.

Question 59

Two companies that produce 4 and 6 cylinder horizontally opposed engines:

Answer 59

Continental, | Textron-Lycoming

Question 60

Cooling systems use a mix of water and ______.

Answer 60

Ethylene glycol.

Question 61

_______ is welded to the face of many exhaust valves that operate at high temps.

Answer 61

Stellite

Question 62

An assembly fit in which the hole is smaller than the part that fits into it.

Answer 62

Interference fit.

Question 63

A reciprocating engine piston that is not round.

Answer 63

Cam-ground piston

Question 64

4 types of piston heads:

Answer 64

Recessed. Truncated cone. Domed. Cupped.

Question 65

3 types of piston rings:

Answer 65

Compression. Oil control. Oil scraper/wiper.

Question 66

Almost all piston rings are made of _______.

Answer 66

Cast iron.

Question 67

T/F | Piston rings used in chrome plated cylinders must not be plated.

Answer 67

True

Question 68

The wear between the cylinder ring and cylinder wall produces a seal and allows the rings to ______.

Answer 68

Seat.

Question 69

3 methods of heat transfer:

Answer 69

Conduction. Radiation. Convection.

Question 70

A four cylinder crankshaft in a continental engine has 3 ______ and 4 _____.

Answer 70

Main journal bearings. | Throws.

Question 71

Component of a crankshaft that traps debris by centrifugal force.

Answer 71

Sludge plug.

Question 72

3 different methods of attaching props to engine crankshafts:

Answer 72

Splined shaft. Tapered shaft. Flanged shaft.

Question 73

Part of crankshaft that absorbs torsional vibrations.

Answer 73

Dynamic counterweights.

Question 74

Serves as the foundation of the engine and attaches the engine to the airframe.

Answer 74

Crankcase

Question 75

Horizontally opposed engine crankcases are cast of _____.

Answer 75

Aluminum alloy

Question 76

Crankshafts are supported in the crankcase by ______.

Answer 76

Plain bearings.

Question 77

T/F | Crankshafts do not use any type of ball bearing insert or bushing.

Answer 77

True.

Question 78

Parts of the valve train:

Answer 78

``` Camshaft, Cam lobe, Hydraulic valve lifter, Pushrod, Rocket arm, Valve springs, Poppet valve. ```

Question 79

Used to maintain zero clearance in the valve train:

Answer 79

Hydraulic valve lifter | Zero lash valve lifter

Question 80

T/F | Most radial engines use hydraulic valve lifters.

Answer 80

False.

Question 81

The valve clearance when the engine is hot is ________ than the clearance when it is cold.

Answer 81

Greater.

Question 82

The cylinder barrel of a modern reciprocating engine is made of _______ or _______.

Answer 82

Chrome moly. | Chrome nickel moly.

Question 83

The part of the cylinder that fits into the crankcase.

Answer 83

Skirt.

Question 84

A type of cylinder in which the diameter at the top is smaller than the diameter at the middle.

Answer 84

Choke-ground/bored

Question 85

T/F | The diameter of a cam-ground piston perpendicular to the wrist pin is smallest.

Answer 85

False.

Question 86

A pin that is not clamped to either the connecting rod nor the piston is called ______

Answer 86

Full floating wrist pin

Question 87

The bearing on the small end of a connecting rod is a ______.

Answer 87

Bronze bushing

Question 88

The throws on a crankshaft of a 4 cylinder HO engine are ______ degrees apart.

Answer 88

180

Question 89

The camshaft of a HO engine turns at _______ the speed of the crankshaft.

Answer 89

One half

Question 90

The bearing used in most rocker arms is a _____

Answer 90

Bronze bushing