AEIS CHAPTER 4

Question 1

(ICAO) stands for

Answer 1

International Civil Aviation Organisation

Question 2

The ICAO defines the sea-level ISA as:
Pressure = ?
Temperature = ?
Humidity = ?

Answer 2

Pressure = 0 psi, Temperature: 15deg.celcius, Humidity: 0%

Question 3

Define lapse rate

Answer 3

rate of change in temperature with altitude

Question 4

Standard pitot-static head or probe is mainly used on i)

Answer 4

light aircraft

Question 5

what is the key disadvantage of a standard pitot-static head or probe and what is done to combat it?

Answer 5

pressure probe prone to be blocked by sand and insects. thus a special “trapped” form of pressure probe is used

Question 6

why is the electrically-heated pitot static tube used?

Answer 6

prevent ice formation at high altitudes or cold climates

Question 7

what will happen if an electrically-heated pitot static tube is not used in cold climates?

Answer 7

probe openings get blocked, causing false indications or complete failure to the indicators

Question 8

why is it better to seperate the static vent and pitot head?

Answer 8

static pressure obtained from pressure heads is not always a true value of still air pressure

Question 9

pitot tube is usually located at i) for aircrafts operating at speeds above sound

Answer 9

fuselage nose

Question 10

For aircrafts operating below speed of sound (343m/s), pitot tube is usually located i), ii), iii)

Answer 10

ahead of wing tip, ahead of vertical stablizer, or at side of fuselage nose section

Question 11

where are static vents located?

Answer 11

on the skin of fuselage, one on each side of the fuselage

Question 12

why are the static vents interconnected?

Answer 12

to minimise dynamic pressure effects

Question 13

sensitive altimeter works through the i) which will move the ii) that drive the iii)

Answer 13

i) expansion and contraction of the water capsule
ii) mechanical linkages that drive the
iii) altimeter needles accordingly

Question 14

when does the water capsule in a sensitive altimeter expands?

Answer 14

when aircraft is ascending, and static pressure decreases

Question 15

when does the water capsule in a sensitive altimeter contracts? and comment on the static pressure

Answer 15

when aircraft is descending, and static pressure increases

Question 16

compare the sensitive altimeters to a servo-assisted altimeter

Answer 16

servo-assisted altimeter are more accurate through use of electronics and motors

Question 17

(VSI) stands for

Answer 17

vertical speed indicators

Question 18

what is the function of a VSI

Answer 18

used to indicate if the aircraft is ascending, descending or in level-flight

Question 19

if the VSI indicates 0, what does it mean

Answer 19

it means that the aircraft is in level-flight

Question 20

VSI operates from i) , it is a ii) instrument

Answer 20

static pressure, differential pressure

Question 21

during descend, the capsule in the VSI i) to indicate a descend because static pressure ii)

Answer 21

expands, increases

Question 22

during ascend, the capsule in the VSI i) to indicate a ascend because static pressure ii)

Answer 22

contracts, decreases

Question 23

(ASI)

Answer 23

Airspeed indicator

Question 24

(ASI) measures the i) to indicate the speed of the aircraft

Answer 24

difference between pitot and static pressure

Question 25

when the aircraft is parked on the ground, the two pressures in the (ASI) is i)

Answer 25

equal

Question 26

which type of aircraft are required by the FAA to have Airspeed Indicator Markings?

Answer 26

aircraft weighing 12500 pounds or less

Question 27

What should be the ASI reading prior to takeoff

Answer 27

zero

Question 28

what should be the ASI reading prior to takeoff when there is a strong wind blowing into the pitot tube?

Answer 28

higher than zero

Question 29

what is used to measure the difference between pitot and static pressure in an ASI

Answer 29

a sensitive differential pressure gauge

Question 30

during acceleration at level flight, ascend or descent, the capsule in an ASI i)

Answer 30

expands

Question 31

during deceleration at level flight, ascend or descent, the capsule in an ASI i)

Answer 31

contracts

Question 32

when the pitot tubes are blocked when the aircraft is ascending at constant speed, the reading on the ASI will i) - read

Answer 32

over-read

Question 33

when the pitot tubes are blocked when the aircraft is descending at constant speed, the reading on the ASI will i) - read

Answer 33

under-read

Question 34

when the static ports are blocked when the aircraft is ascending at constant speed, the reading on the ASI will i) - read

Answer 34

under-read

Question 35

when the static ports are blocked when the aircraft is descending at constant speed, the reading on the ASI will i) - read

Answer 35

over-read

Question 36

when the pitot tubes leak when aircraft is ascending or descending, the reading on the ASI will i) - read

Answer 36

under-read

Question 37

when the static ports leak when aircraft is ascending or descending, the reading on the ASI will i) - read

Answer 37

over-read

Question 38

IAS refers to

Answer 38

indicated airspeed

Question 39

IAS =

Answer 39

airspeed indicator reading + instrument error correction

Question 40

CAS refers to

Answer 40

calibrated airspeed

Question 41

CAS =

Answer 41

IAS + pressure error correction

Question 42

EAS refers to

Answer 42

equivalent airspeed

Question 43

EAS =

Answer 43

CAS + compressibility error correction

Question 44

TAS refers to

Answer 44

True Airspeed

Question 45

TAS =

Answer 45

EAS + density error correction

Question 46

mach number is the ratio between i) and ii)

Answer 46

true airspeed(TAS) and the local speed of sound

Question 47

machmeter utilises the aircraft's i) system to generate M

Answer 47

pitot-static system

Question 48

high speed aircraft, including airlines and business jets, have i) mach numbers

Answer 48

critical

Question 49

what happens if the critical mach numbers is exceeded?

Answer 49

it will create shock waves on the aerofoils resulting in buffet or mach tuck

Question 50

what is mach tuck

Answer 50

aircraft nose pitching downwards

Question 51

what is buffeting

Answer 51

where wings experience aerodynamic turbulence

Question 52

when aircraft is at a higher altitude at the same TAS, the mach number will i) because speed of sound ii)

Answer 52

increase, decreases

Question 53

machmeter makes use of a i) capsule and a ii) capsule

Answer 53

altimeter, airspeed

Question 54

airspeed capsule in a machmeter accepts i) inputs

Answer 54

pitot-static

Question 55

altitude capsule in a machmeter accepts i) inputs

Answer 55

static

Question 56

when the pitot tubes are blocked and the aircraft is ascending at constant speed, the mach number will i)-read

Answer 56

over-read

Question 57

when the pitot tubes are blocked and the aircraft is descending at constant speed, the mach number will i)-read

Answer 57

under-read

Question 58

when the static ports are blocked and the aircraft is ascending at constant speed, the mach number will i)-read

Answer 58

under-read

Question 59

when the static ports are blocked and the aircraft is descending at constant speed, the mach number will i)-read

Answer 59

over-read

Question 60

pitot-static testers are used to i)

Answer 60

check for leaks

Question 61

how do pitot-static testers check for leaks?

Answer 61

by simulating pitot and static pressures at different airspeeds and altitudes to the flight instruments

Question 62

EFD refers to

Answer 62

electronic flight display

Question 63

the high tech smart sensors for aircraft instrumentation are more i) and require less ii) compared to analogue counterparts

Answer 63

reliable, maintenance