lionel wrote:
Aithre doesn’t give any weight, but it is an order of magnitude smaller in volume, so…
The article mentions 5lb weight.
chflyer wrote:
The article mentions 5lb weight.
Ah, my own “rest of the world”-centrism, I did a search for “kg” not for “lb”. 
Peter wrote:
get the claimed 97% O2 just by pushing air through the zeolite crystals
It is the same principle in the Inogen systems.
Arne wrote:
It is the same principle in the Inogen systems.
So the big difference between the Inogen systems and the Aithre system is that one uses a rechargeable battery for power and other requires permanent direct power supply? Given the increasing safety of the batteries being used, one could wonder if the avoidance of a battery justifies the >4x price difference, unless there is something else.
Once one has invested in an O2 system with tank(s) and “smart” delivery system such as the MH EDS there would seem to be little incentive to migrate, given the large cost investment. One would really want to get away from having to manage O2 supply.
chflyer wrote:
So the big difference between the Inogen systems and the Aithre system is that one uses a rechargeable battery for power and other requires permanent direct power supply?
The Inogen systems are (portable) medical systems, and is priced in general monetary units. The Aithre system is an aviation system and is priced in AMUs.
I tested 2 Inogen G6 units this summer flying until 17kft on different configuration in long flights (+4h), 1by1 and 2by1 (2pax per unit) and the results were very good. It is a on demand equipment so it is mean that the optimun way or working is 1by1 but in 2by1 it maintains for the 2 persons the level of 90% at power level 4 (it has 6 level). Of course, it depends of several factor and specially on pilot adaptability to hipoxia.
I continue testing.
JL_TM wrote:
I continue testing.
Keep us posted. I have not yet tested 2 people on my G5 but I have all the splitters. Just need one of the girls to want to go on a test flight with me around the Matterhorn.
I use my G5 much more than I had originally anticipated. Any time I’ll be over FL75 for a while I put it on – keeps the o2 at 98-99%, and I feel good.
IIUC oxygen generators work by taking in the surrounding air and concentrating it.
Does it therefore have to work much harder the higher you get and the more people in the aircraft?
Secondly, if you have more than one concentrator for say 2 or 3 passengers, wouldn’t each concentrator be fighting for the same air?
Sorry if it seems a silly question but my only experience of an oxygen generator was the one my dad had for medical reasons. It was electrically driven and would use more power some days than others.
The ones in this discussion work by removing most of the nitrogen, using a process of absorption by zeolite crystals which are then vented to get rid of the absorbed stuff.
There is plenty of air available in the cockpit
Just as well, since the nitrogen is just vented back into the cockpit… So if you ran 100 of these O2 generators in a TB20 you would probably find the cockpit air is 99% nitrogen and a) the generator cannot extract any oxygen and b) the occupants are dead because even when you are on O2 most of the air inhaled is just ambient air
