Oxygen requirments
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Oxygen requirments
Any one help with the requirements for the use of oxygen in light aircraft.
Aviation theory centre book Human performance and limitations says anything over 10,000 feet. BoB Taits sought of concludes the same however in their sample test questions thay have the correct answer as 14,000ft
Anyone know which publication has the casa ruling?
thanks
Aviation theory centre book Human performance and limitations says anything over 10,000 feet. BoB Taits sought of concludes the same however in their sample test questions thay have the correct answer as 14,000ft
Anyone know which publication has the casa ruling?
thanks
Try this link http://casa.gov.au/download/orders/Cao20/2004.pdf
if it doesn't work try this one and loom at CAO 20.4 http://casa.gov.au/rules/orders/020.htm
In any case this is the section you need.
if it doesn't work try this one and loom at CAO 20.4 http://casa.gov.au/rules/orders/020.htm
In any case this is the section you need.
6 SUPPLEMENTAL OXYGEN REQUIREMENTS FOR UNPRESSURISED AIRCRAFT
Supplemental oxygen for flight crew members
6.1 A flight crew member who is on flight deck duty in an unpressurised aircraft must be provided with, and continuously use, supplemental oxygen at all times during which the aircraft flies above 10 000 feet altitude.
6.2 A flight crew member must, in respect of any period during which the member is not on flight deck duty, be provided with the amount of supplemental oxygen that is provided to a crew member in accordance with paragraph 6.3.
Supplemental oxygen for flight crew members
6.1 A flight crew member who is on flight deck duty in an unpressurised aircraft must be provided with, and continuously use, supplemental oxygen at all times during which the aircraft flies above 10 000 feet altitude.
6.2 A flight crew member must, in respect of any period during which the member is not on flight deck duty, be provided with the amount of supplemental oxygen that is provided to a crew member in accordance with paragraph 6.3.
10k for pilots at control seat 14k for pax and cabin crew
While the regulation may be as stated above, having spent a fair bit of time in the last few months flying around with an oximeter attached to my finger, I would question the scientific basis of this regulation. The reg. doesn't specify, but it probably should be "density altitude of 10k/14k".
On a summer's day in northern Australia the Density Altitude may well be closer to 12,000' - it was 18o C at 10,000' between YEML and YBTL about 13:00 last Sunday. 14,000' may well be more like 16'000' DA - which I suspect would have the majority of pax and cabin crew off in the Land of Nod before long.
My understanding is that to for the brain to function effectively, the oxygen saturation of the blood should be 90% or better.
At 10,000' my % O2 saturation tends to sit around 90 (deliberate deep breathing brings it up to about 96%) and my young (?) mate Jaba is only marginally better. At 14,000' a couple of weeks ago a conserver nasal cannula would not keep my O2 saturation above 90% and I had to change to a full face mask.
After a few hours of flying at 9 or 10,000' in summer I suspect one's brain function may well be less than ideal. My understanding is that at night one's brain is even more sensitive to O2 deprivation, and women have a higher demand for O2 than men - which may explain why Mrs FTDK goes to sleep whenever she travels with me.
Dr
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The 'book' answer might not be right for you. People vary, some people need to use oxygen before the 'book' height just as some people have a lot more problems with altitude sickness and adjusting to altitude. If you are planning lots of flying high enough for it to be an issue, you could consider getting a finger-tip pulse oximeter. The following URL tells you more about this:
http://www.aeromedix.com/aeromedix_a...eox/index.html
This article has some links to other articles that are worth reading.
http://www.aeromedix.com/aeromedix_a...eox/index.html
This article has some links to other articles that are worth reading.
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Excellent posts regarding this sometimes insidious hazard.
Someone ('cats_five')mentioned it's effect people differently. That's spot on. Also a human being at rest requires less O2 than someone dealing with an emergency at ALT, the latter requiring more, esspecially at night seeing (pun not intended) the eyes need more O2 to function correctly.
CW
p.s............hey Dr, don't forget the 'Conty' up that high, she'll be gasping also !
Someone ('cats_five')mentioned it's effect people differently. That's spot on. Also a human being at rest requires less O2 than someone dealing with an emergency at ALT, the latter requiring more, esspecially at night seeing (pun not intended) the eyes need more O2 to function correctly.
CW
p.s............hey Dr, don't forget the 'Conty' up that high, she'll be gasping also !
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12000?
The rest of the world only needs oxygen above 12000 ft, but Australians are "uniquely different", and need it above 10000 ft.
I once flew a south american man around for about a week, and he told me he and his family lived in a village that was 18000 ft amsl. It's interesting.
I also remember RFDS pilots who used oxygen after takeoff at night, because it improves night vision.
Ed Hilary wrote that the 80 lb backpack "seemed much lighter when he turned on the oxygen." He was about 25000ft amsl.
It's very real, and must be taken seriously. But we need to have a good look at the oxygen legislation, and the transition level in Australia. Turbocharged engines have very limited advantage here, as they are often limited to 8500 ft amsl.
We should lift the oxygen level to 12000,like the rest of the world, and lift the transition level to about 18,000ft.
I once flew a south american man around for about a week, and he told me he and his family lived in a village that was 18000 ft amsl. It's interesting.
I also remember RFDS pilots who used oxygen after takeoff at night, because it improves night vision.
Ed Hilary wrote that the 80 lb backpack "seemed much lighter when he turned on the oxygen." He was about 25000ft amsl.
It's very real, and must be taken seriously. But we need to have a good look at the oxygen legislation, and the transition level in Australia. Turbocharged engines have very limited advantage here, as they are often limited to 8500 ft amsl.
We should lift the oxygen level to 12000,like the rest of the world, and lift the transition level to about 18,000ft.
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US Navy many years ago pilot oxygen was required above 10,000 day and 5,000 night (night vision). Under the bag in the back seat doing instrument as students many never bothered with oxygen (mask a pain to wear) and operating up to near 20,000. Didn't seem to bother - comes from being young and super fit I guess. WW1 tales often mention of operating at 20,000 - once again young men.
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US Navy many years ago pilot oxygen was required above 10,000 day and 5,000 night (night vision). Under the bag in the back seat doing instrument as students many never bothered with oxygen (mask a pain to wear) and operating up to near 20,000. Didn't seem to bother - comes from being young and super fit I guess. WW1 tales often mention of operating at 20,000 - once again young men.
BTW the 18,000' mentioned in another post is pretty close to the limit that humans can acclimatise to for long-term occupation. However part of the physiological acclimatising is increasing the density of red blood cells in the blood which makes it thicker, so strokes / embolisms become more of a problem, especially if one gets dehydrated.
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The reg. doesn't specify, but it probably should be "density altitude of 10k/14k".
Time of Useful Consciousness etc are all predicated on the partial pressure of oxygen (ppO2) and therefore it's ability to move from the lungs into the bloodstream. ppO2 is of course directly proportional to the atmospheric pressure.
Therefore you could say that the regs should read "FL100 and FL140", but hopefully anywhere over A100 we are on pressure altitude anyway!
Happy to have my meagre HF knowledge shot down by the doctor or anyone else!
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8500???
FTDK
If you were flying west, VFR without oxygen what is the max height you could fly at?(Without being "non standard)
There is a gap from 8500 to 12500 that is unusable. The transition layer should be much higher.
If you were flying west, VFR without oxygen what is the max height you could fly at?(Without being "non standard)
There is a gap from 8500 to 12500 that is unusable. The transition layer should be much higher.
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Bushy
You should know that the good Dr only ever experiences VFR under the most desperate of circumstances (like if I fly it
).
The only reason he flies IFR.......is coz there is nothing better!
J
You should know that the good Dr only ever experiences VFR under the most desperate of circumstances (like if I fly it
).The only reason he flies IFR.......is coz there is nothing better!
J
FTDK
If you were flying west, VFR without oxygen what is the max height you could fly at?(Without being "non standard)
There is a gap from 8500 to 12500 that is unusable. The transition layer should be much higher.
If you were flying west, VFR without oxygen what is the max height you could fly at?(Without being "non standard)
There is a gap from 8500 to 12500 that is unusable. The transition layer should be much higher.
Ya need to read the SOPs for ForkAir - "No VFR operations above 1500' AGL"!
Dr
Last edited by ForkTailedDrKiller; 19th Feb 2008 at 08:22.
Not to pick a fight with a Doctor, but wouldn't it be pressure altitude, rather than density altitude that matters most in this regard???
Dr
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The rest of the world only needs oxygen above 12000 ft
Although the same regulations also "recommend" oxygen above 10,000 during day and 5,000 at night.
I worked with some guys that were heavy smoker's and on night freight they wouldn't and didn't like going above 5000'.
I like the RFDS technique Bushy, unless it was used to cure the old hangover!
I like the RFDS technique Bushy, unless it was used to cure the old hangover!