Oxygen

Question 1

why is oxygen important

Answer 1

lack of oxygen leads to hypoxia

Question 2

physiological Effects

Answer 2

above 33,000ft, the effects of hypoxia start to take effect. above 40,000ft the effects are more noticeable

Question 3

altitude effects with Oxygen at 30,000ft

Answer 3

Will full supply, no ill effects

Question 4

altitude effects with Oxygen at 35,000ft

Answer 4

With undilute oxygen, judgement and mental reactions, unimpaired

Question 5

altitude effects with Oxygen at 38,000ft

Answer 5

You can go above this height without pressurisation

Question 6

altitude effects with Oxygen at 43,000ft

Answer 6

Max alt with appropriate breathing equipment, can provide get down protection

Question 7

altitude effects with Oxygen at 63,000ft

Answer 7

without suitable pressurisation, bodily fluids boil at this height

Question 8

Pressure breathing equipment

Answer 8

aircrew personal equipment and the a/c oxygen supple must be capable at providing the same condition as that encounter at 40,000ft when breathing undiluted.

does this with pressure breathing, personal equipment and demand type regulators are used. 3 seconds after the loss of cabin pressure these systems will kick in.

Question 9

Altitude effects without oxygen at 4000ft

Answer 9

Night vision effected

Question 10

Altitude effects without oxygen at 10,000ft

Answer 10

Efficiency not seriously effected

Question 11

Altitude effects without oxygen at 15,000ft

Answer 11

Danger zone; over confidence and judgement affected

Question 12

Altitude effects without oxygen at 20,000ft

Answer 12

Loss of coordination, double vision and danger of collapse

Question 13

Altitude effects at without oxygen at 25000ft,

Answer 13

loss of consciousness after 25000ft, followed by death

Question 14

Pressure suit

Answer 14

must be worn to simulate pressurised cabin. all military a/c capable of 40,000ft are fitted with cabin pressurisation and the pressure equiptment is only used in emergency

Question 15

Effects on breaking cabin pressure (combat damage)

Answer 15

Since the pressure difference is so big suitable equipment must be worn to protect in the event that the cabin pressure is broken.

Question 16

Oxygen sources.

Answer 16

O2 is stored either in a gas form or liquid form, depending on the system. its highly volatile when it contacts oil, grease or any petroleum.

Must be 99.5% oxygen whatever the supply is and not contain more that 0.005mg of water per 1L of O2.

cant use other types of oxygen in a/c as they contains impurities which isnt suitable for breathing.

Question 17

Gaseous oxygen

Answer 17

Most commong form because its easy to work it and transport plus its available at most airports., disadvantage as you dealing with compressed gasses and the weight of the cylinders.

Question 18

Liquid oxygen (LOX)

Answer 18

Most military a/c carry LOX, expansion ration is 7 times greater than gas oxygen. need less space that gas systems but has its own problems when handling low temp liquids. needs to be refilled often because it losses from venting systems.

Question 19

Chemical or solid O2

Answer 19

Convenient method of carrying O2. many large a/c use solid oxygen generators as a supplemental source of O2. consist of a shapes block of chemical like sodium chlorate encased in protective steel case.

Question 20

How Chemical or solid O2 systems work

Answer 20

chemical is ignited and O2 is a by product of this. ignited by electrically or mechanically. safe to use and store because no high pressure is involved, downside being that the heat generate is enough to cause damage if its not dissapated correctly.

Question 21

Mechanically seperated O2

Answer 21

new process thats extracting O2 from the air by a mechanical process. air pull into molecular sleeve, nitrogen is caught oxygen rich gas passes through.

appears to replace all other types because economy of weight and space and A/c isnt dependant on ground facilities.

Question 22

O2 Warnings and safety.

Answer 22

Dont mix Aviation O2 with other types as they have a higher water precentage which would freeze

dont smoke near 02 station

dont use oil, grease etc near compresed 02 as it will combust

clean thoroughly and in accordance with regs

use approved adhesives and compounds only

use protective caps , sealed in polythene bad to stop damage from FoD

use only certified materials to stop contamination, dont be lax

only use specified lubes

only refill to set pressures to avoid damage to containers

read health and safety

Question 23

02 storage

Answer 23

only fill between 1800 and 2400 psi and there are safety systems in place to stop failure. pressure reducing valves etc. often repeat pipework to stop 1 leak causing failure

Question 24

Standard O2 system layout order

Answer 24

Charging vavle
filter
NRV to O2 tanks. (O2 tanks have cylinder valve)                                                 
Filters
content valve
reducing valve
delivery

Question 25

Continous flow

Answer 25

provides the earliest method of supplying oxygen. however its wasteful because it continuous. sometime used as emergency supplies

Question 26

Demand oxygen

Answer 26

fixes the downside of the continuous flow system., pressure demand system which varies the flow by the inspiratory rate of the user

most are demand systems, design and principles are all the same. can be panel mounted, man mounted and seat mounted

Question 27

02 regulators continuous flow

Answer 27

Low demand systems, Allows 02 from storage cylinders regardless of how much you breathing, simple and low cost. used when mask drop from ceiling in airlines.

Question 28

02 regulators Pressure demand

Answer 28

02 is fed from storage systems to demand regulators. amount depends on how much the user is breathing, the amount of oxygen is increased the higher the alt.

Question 29

3 switches on pressure demand regulator

Answer 29

-on/off lever, normally wire locked in ON position

-Normal/100% lever, allow 100% 02 regardless of alt
because of blanking off of air mix valve

-emergency /press to test mask toggle, allows delivery of additional pressure at all alts

Question 30

Distribution (panel mounted)

Answer 30

For seat mounted, delivery pipe work routed from 02 source via regulator which is panel mounted. hoses ether mount directly into seat or straight in PEC. inlet then goes into mask hose

Question 31

Distribution (seat mounted)

Answer 31

02 hoses passes mask and goes into man portion

Question 32

02 distribution order (non ejector seat)

Answer 32

Source
Reg p-m (panel mount)
mask

Question 33

02 distribution order ( ejector seat)

Answer 33

Source
reg p-m
pec
mask

or
source
PEC
reg s-m 
PEc
Mask

or

Source
PEC
reg-m-m
mask

Question 34

Wide bore 02 hoses

Answer 34

only used after pressure is stepped down. made of natural or vulcanise rubber, reinforces by galvanised steel wire and covered in rubber gauze. anti kink and multiple connector available

Question 35

Flow indicator

Answer 35

tappings allow the variations in pressure to operate flow indicator

Question 36

contents indicator

Answer 36

remote connector attached to liquid 02 systems to see the pressure. Gauge operated in pressure but calibrated in quantities of FULL

Question 37

charging

Answer 37

only use certified equipment and charge to full pressure. high pressure 02 canisters are dangerous to everyone

dont let

Question 38

Why cant canisters be completely emptied

Answer 38

Air can get in and create moisture, leading to corrosing in canister. this can free inside the mask and can fail with catastrophic results.