Recip Final

Question 1

what are the two cylinder valves

Answer 1

Intake - where air/fuel mixture enters the piston exhaust - where exhaust gasses leave the cylinder

Question 2

what is the otto cycle

Answer 2

standard compression cycle in a 2 or 4 stroke piston engine

Question 3

what is a compression ratio

Answer 3

the compression of the total volume of the cylinder when piston is at BDC and TDC. increase in manifold pressure = increase in compression ratio

Question 4

TDC stands for

Answer 4

Top dead center

Question 5

BDC stands for

Answer 5

Bottom dead center

Question 6

2 types of oil pumps are

Answer 6

gear pump and Gerotor pump

Question 7

how is compression ratio calculated

Answer 7

the cylinder volume at BDC divided b the volume at TDC

Question 8

what is horespower? how is it calculated

Answer 8

horsepower is a standard unit of mechanical power.

1HP = number of foot-pounds divided by 33,000

Question 9

what does PLANK stand for

Answer 9

P = IMEP (indicated manifold effective pressure)

L = length of stroke in feet

A = area of piston

N = # of power strokes per minute

K = Number of cylinders

Question 10

what is the difference between break and indicted horsepower

Answer 10

indicated HP - theoretical, does not account for friction.

Break HP - actual horsepower delivered by the engine to the propeller

Question 11

what are the 6 functions of oil

Answer 11

reduce friction
absorb heat
seals and cushions
cleans
protects against corrosion

Question 12

what is flash point

Answer 12

temperature at which oil gives off ignitable vapors

Question 13

what is cloud point

Answer 13

temperature at which wax separates and solidifies into crystals

Question 14

what is fire point

Answer 14

temperature at which there are sufficient vapors to support a flame

Question 15

pour point

Answer 15

the lowest temperature that oil can flow or be poured

Question 16

how are aircraft oils classified

Answer 16

oils are classified by viscosity levels. higher viscosity = a higher oil number

Question 17

what is viscosity

Answer 17

a liquids resistance to flow. high viscosity = a thicker liquid

Question 18

what are the four types of oil used for aircrafts

Answer 18

mineral
ashless dispersant
synthetic
multi viscosity

Question 19

what are the two types of oil systems

Answer 19

wet sump - oil is located within the crankcase. simpler

dry sump - oil is located in a separate oil tank. most common in radial engines. uses a scavenge pump to disperse oil

Question 20

what is a pressure relief valve

Answer 20

a valve that maintains a constant pressure within the oil system by bleeding off excess. can be adjusted using a screw or washers

Question 21

3 types of check valves

Answer 21

ball, cone, and swing

Question 22

what are bypass valves used for

Answer 22

allowing oil to bypass the oil cooler until it is brought up to temperature

Question 23

2 types of oil filters

Answer 23

full flow and bypass

Question 24

what is SOAP

Answer 24

Spectrometric oil analysis program

Question 25

what are the different types of icing

Answer 25

throttle ice fuel evaporation impact ice

Question 26

what is the idle valve in the pressure carburetor used for

Answer 26

maintaining fuel flow at idle speeds

Question 27

how is the mixture controlled in a carburetor

Answer 27

controlled by varying pressure between the two fuel chambers, A and B

Question 28

what is density altitude

Answer 28

the pressure altitude corrected for non standard temperature variations. affects the takeoff distance as well as rate of climb

Question 29

what effect does carb heat have on the fuel/air mixture

Answer 29

lowers the density of the air causing mixture to become more rich

Question 30

what happens when an aircraft climbs to altitude

Answer 30

mass and density of air will decrease. the same volume of air provides less oxygen

Question 31

what is MAP and where is it measured?

Answer 31

Maximum absolute pressure measured after the throttle plate (butterfly valve)

Question 32

engine operation on a clear cool day can lead to _______ if the relative humidity is too high

Answer 32

Carburetor icing

Question 33

why is the carburetor pre-heater not used on takeoff

Answer 33

causes loss of power, rough running engine and detonation

Question 34

where is the "hot spot" in the 0-320 engine

Answer 34

in the oil sump. heats air to improve vaporization

Question 35

what denotes a "standard day"

Answer 35

29.92 InHG | 15 degrees celcius

Question 36

what happens to engine power as an aircraft climbs to altitude

Answer 36

power reduces due to the reduced air density

Question 37

how does an increase in carburetor air temperature affect BMEP

Answer 37

warmer air will decrease BMEP