ENVIRONMENTAL

Question 1

is a process in which conditioned air is pumped into the cabin of an aircraft or spacecraft, in order to create a safe and comfortable environment for passengers and crew flying at high altitudes

Answer 1

Cabin pressurization

Question 2

Aircraft are flown at high altitudes for two reasons

Answer 2

1. An aircraft flown at high altitude consumes less fuel for a given airspeed than it does for the same speed at a lower altitude because the aircraft is more efficient at a high altitude.
2. Bad weather and turbulence may be avoided by flying in relatively smooth air above the storms.

Question 3

An aircraft flown at _____ consumes ____ fuel for a given airspeed than it does for the same speed at a lower altitude because the aircraft is more efficient at a high altitude

Answer 3

high altitude, less

Question 4

________ may be avoided by flying in relatively smooth air above the storms

Answer 4

Bad weather and turbulence

Question 5

typically maintains a cabin pressure altitude of approximately 8,000 feet at the
maximum designed cruising altitude of an aircraft. . This
prevents rapid changes of cabin altitude that may be
uncomfortable or cause injury to passengers and crew

Answer 5

cabin pressurization system

Question 6

In addition, it permits a reasonably
fast exchange of air from the inside to the outside of the
cabin. This is necessary to eliminate odors and to remove
stale air.

Answer 6

cabin pressurization system

Question 7

In airliner, cabin pressure is ______ to the pressure
outside the aircraft, in order to reduce the stress in the
aircraft fuselage

Answer 7

proportional

Question 8

In typical ________, the cabin altitude is programmed to rise gradually from the
altitude of the airport of origin to a regulatory maximum of 8,000feet or 2,400 meter.

Answer 8

commercial passenger flight

Question 9

The _________ is maintained
while the aircraft is cruising at its max altitude then gradually reduces during the decent of the aircraft, until it matches
the ambient air pressure at the destination

Answer 9

cabin pressure

Question 10

the actual height above sea level at which the aircraft is flying

Answer 10

Aircraft altitude

Question 11

the temperature in the area immediately surrounding the aircraft.

Answer 11

Ambient temperature

Question 12

cabin pressure in terms of equivalent altitude above sea level.

Answer 12

Cabin altitude

Question 13

the pressure in the area immediately surrounding the aircraft .

Answer 13

Ambient pressure

Question 14

the difference in pressure between the pressure acting on one side of a wall and the pressure acting on the other side of the wall.

Answer 14

Differential pressure

Question 15

In aircraft air-conditioning and pressurizing systems, it is the difference between cabin pressure and atmospheric pressure.

Answer 15

Differential pressure

Question 16

The lower partial pressure of oxygen at altitude reduces the alveolar oxygen tension in the lungs and subsequently in the brain, leading to sluggish thinking, dimmed vision, loss of consciousness, and ultimately death.

Answer 16

Hypoxia

Question 17

Hyperventilation, the body’s most common response to hypoxia, does help to partially restore the partial pressure of oxygen in the blood, but it also causes carbon dioxide (CO2) to out-gas, raising the blood pH and inducing alkalosis.

Answer 17

Altitude sickness

Question 18

The low partial pressure of gases, principally nitrogen (N2) but including all other gases, may cause dissolved gases in the bloodstream to precipitate out, resulting in gas embolism, or bubbles in the bloodstream.

Answer 18

Decompression sickness

Question 19

As the aircraft climbs or descends, passengers may experience discomfort or acute pain as gases trapped within their bodies expand or contract

Answer 19

Barotrauma

Question 20

provides cabin
pressure regulation, pressure relief, vacuum relief, and the means for selecting the desired cabin altitude in the isobaric and differential range.

Answer 20

cabin pressure control system

Question 21

dumping of the cabin pressure is a function of
the _______. A cabin pressure regulator, an outflow valve, and a safety valve are used to accomplish
these functions.

Answer 21

pressure control system

Question 22

controls cabin pressure to a selected value in the isobaric range and limits cabin pressure to a preset differential value in the differential range.

Answer 22

cabin pressure regulator

Question 23

When an aircraft reaches
the altitude at which the difference between the pressure inside and outside the cabin is equal to the highest differential pressure for which the fuselage structure is designed, a further increase in aircraft altitude will result in a corresponding increase in cabin altitude.

Answer 23

cabin pressure regulator

Question 24

is used to PREVENT the MAXIMUM DIFFERENTIAL PRESSURE , for which the fuselage was designed, from being exceeded.

Answer 24

Differential control

Question 25

is determined by the structural strength of the cabin and often by the relationship of the cabin size to the probable areas of rupture, such as window areas and doors.

Answer 25

Differential pressure

Question 26

is a combination pressure relief, vacuum relief, and dump valve.

Answer 26

cabin air pressure safety valve

Question 27

prevents cabin pressure from EXCEEDING A PRE DETERMINED differential pressure above ambient pressure

Answer 27

pressure relief valve

Question 28

prevents ambient pressure from exceeding cabin pressure by allowing external air to enter the cabin when ambient pressure exceeds cabin pressure

Answer 28

vacuum relief

Question 29

actuates the dump valve. When this switch is positioned to ram, a solenoid valve opens, causing the valve to dump cabin air into the atmosphere.

Answer 29

flight deck control switch

Question 30

The degree of _____ and the _____ of the aircraft are limited by several critical design factors. Primarily, the fuselage is designed to withstand a particular maximum cabin differential pressure.

Answer 30

pressurization, operating altitude

Question 31

indicates the difference between inside and outside pressure. This gauge should be monitored to assure that the cabin does not exceed the maximum allowable differential pressure

Answer 31

cabin differential pressure gauge

Question 32

is also provided as a check on the performance of the system. In some cases, these two instruments are combined into one. A third instrument indicates the cabin rate of climb or descent.

Answer 32

cabin altimeter

Question 33

Advantages of Cabin Pressurization System

Answer 33

This system helps to maintain aircraft cabin pressure at high altitude with great precision and accuracy. It responds to minor changes in cabin pressure with respect to aircraft altitude. It generates ambient atmosphere for passengers and prevents passengers from physiological problems. It also maintains and monitor cabin air quality as per directed by World Health Organization (WHO).

Question 34

Disadvantages of Cabin Pressurization System

Answer 34

decompression

Question 35

is defined as the inability of the aircraft’s pressurization system to maintain its designed pressure differential. This can be caused by a malfunction in the pressurization system or structural damage to the aircraft.

Answer 35

Decompression

Question 36

Decompressions fall into the following two categories:

Answer 36

Explosive decompression Rapid decompression

Question 37

a change in cabin pressure faster than the lungs can decompress, possibly resulting in lung damage. Normally, the time required to release air from the lungs without restrictions, such as masks, is 0.2 seconds. Most authorities consider any decompression that occurs in less than 0.5 seconds to be explosive and potentially dangerous.

Answer 37

Explosive decompression

Question 38

a change in cabin pressure in which the lungs decompress faster than the cabin

Answer 38

Rapid decompression