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Re: Re: The 'Sting' In The Tale Of 15

I reckon I will start wearing masks on long haul flights OR just avoid them altogether.

Re: Re: Re: The 'Sting' In The Tale Of 15

According to some Australian researchers the oxygen levels are better on long-haul flights. They found 15% was a typical in-flight oxygen level, but on long-haul Boeing 747s, it was 17%.

link

Re: Re: Re: Re: The 'Sting' In The Tale Of 15

Was that with or without large sections of the fuselage?

Re: Re: Re: Re: The 'Sting' In The Tale Of 15

That piece is twaddle. They keep talking about higher when they obviously mean lower and v/v.

They say that cabin altitude pressure was higher on short flights. Well, that would mean more oxygen per breath, wouldn't it? - unless they meant that the cabin was pressurised to the pressure found in free air at a higher altitude. Either way, their writing skills need improvement.

Aircraft cabins are pressurised to the pressure found at about 8,000 feet (which saves carrying about a ton of air in a large airliner). However, since all gases are completely mixed in air at all levels (to a first approximation) the proportion of oxygen is still 21%. What matters for chemistry (and biochemistry), though, is the partial pressure, i.e. the pressure the gas would exert if it alone filled that volume. I think this is where our scientifically ignorant journalists are rather losing it.

is rubbish - it still contains 21% but because the pressure is lower that is less mass of oxygen than you would get at sea level and so the partial pressure of oxygen in the lungs is reduced.

Anyway, 8000 feet is only 50% higher than Denver, Colorado, USA and considerably lower than many locations in the Andes and Himalaya.

Re: The 'Sting' In The Tale Of 15

Know its been said before but… here goes. I have been a regular air traveller for the past 34 years , both long haul and short. I simply cannot remember there being all these problems for passengers prior to the smoking ban.

Re: Re: The 'Sting' In The Tale Of 15

But what other confounding factors?

I used to fly quite a bit on business back in the 80s and early 90s. Usually in smoking areas back then.

Rarely was a plane full, especially in business class. So risks emanating from other passengers were fewer. The same could be said for airports.

Secondly some parts of the world, or travel relating to them whether directly (visiting) or indirectly (fellow travellers from those areas or planes that regularly visit those areas) are more risk likely than others. Expansion of air travel to and from such locations has most likely expanded over about the same period that smoking has been reducing and ultimately banned.

On balance I would guess that the likely cause would be reduced maintenance for reasons of cost reduction (or profit enhancement to put the other spin on it) and that such would have been the case in any event.

I rarely fly these days. It has become such a disappointing experience compared to earlier times.


Grant