Van's Air Force
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Practical Oxygen Use
- Thread starter JBHansen
- Start date
Auburntsts
Well Known Member
91.211 lists the legal requirement, right? That said I generally go on O2 above 10K daytime and 8K at night (but I rarely flight at night) . A lot depends on your specific physiology but lower than required by 211 is not a bad idea IMO.
How often depends on your oxygen saturation measured with a pulse oximeter.
I carry my Inogen G5 oxygen concentrator with me on almost all flights, and put o2 on if I'm going to be above about 7-8k for any length of time. It's free, takes about 10 seconds to don, and I just feel better if I fly with o2. As suggested, using a quality pulse oximeter will help you understand your saturation. I think a lot of the "smart" watches have this capability as well. One thing to keep in mind is that oxygen saturation levels are one measurement, and people respond differently to lower levels of oxygen saturation. I have no idea how I will respond, because I just keep my levels in the high 90s. I'd like to get tested in an altitude chamber to see how my body reacts.
David Paule
Well Known Member
In addition to your own physiology, age is a factor. Older and more O2. Another is home elevation. Higher and less O2.
The use of your pulse oximeter will guide you But pay attention to the way you feel, too. Oxygen deprivation is a bit insidious.
Dave
The use of your pulse oximeter will guide you But pay attention to the way you feel, too. Oxygen deprivation is a bit insidious.
Dave
Dan 57
Well Known Member
went around the Mt Blanc today, slightly above FL160 (yes, I'm on the old continent right now), then along the Alps towards Matterhorn, Monta Rosa, and so on, on a 1:40 flight, and my EDS O2D2 started tickling my nostrils with O2 above 10K as selected. Good stuff to have along 
As to when you should "take a hit"? plug in a set of nose canulas and turn on the flow. Let it on until you descend below 8K. I never liked the plastic "hospital mask". can't talk. The "nose hose" works good up to 20K+ above that you need a seal and pressure..... (and a jet)
Auburntsts
Well Known Member
Be cognizant of manufacturer system limitations. For example Mountain High for their pulse demand system states that cannulas can only be used to FL180. Above that a mask must be used.
Personally I've found that even at 10 or 11k for more than an hour, and I'm liable to get a headache unless I'm on oxygen so I generally run it for a cross-country at 10 or above. At night I use it above 8000, I've noticed the difference in my vision, especially color perception at night, between using it and not.
O2 is cheap, use it.
O2 is cheap, use it.
The FAA does not allow canulas above FL180. My guess is that they’re okay if you don’t constantly have your mouth open (but check your pulse oxymeter). And no, you don’t need a pressure mask until much higher than 20K. Nor do you need a jet; I know some who have has their RV10s up to 22000’ or so.
Dugaru
Well Known Member
Another oxygen addict here. I apparently lost the genetic pulmonary lottery and have “naturally” low O2 saturation (makes me glad I never smoked…). So I just set my O2D2 to turn on/off automatically at 5,000 feet so that I don’t forget it. I love that gadget. I fly on BasicMed, so I’m never above 18,000.
PilotjohnS
Well Known Member
There I was, at 10k, cruising back home at night, little moonlight, straining to see if the valley lights would appear through the haze. If I see the valley lights, it means I can come home VFR, if all I see is a hazy glow, it means the coastal fog has returned, and I am doing an IFR approach, or looking ove my shoulder for Mr FAA when I land.
So strainining to see the city lights, I am glad I was on O2 the whole way back. Sharp vision, good brain function, and seeing colors at night makes all the difference.
O2 is cheap insurance.
So strainining to see the city lights, I am glad I was on O2 the whole way back. Sharp vision, good brain function, and seeing colors at night makes all the difference.
O2 is cheap insurance.
Carl Froehlich
Well Known Member
I’m on oxygen any time at 8K’ or above. Using the mountain high O2D2 system with the larger 24.2 cu-ft AL-682 cylinder. Close to all my cross country runs are at 8K’ or above.
Make the investment to have a charging station in your hangar. Get a group of 3-6 people to each get a cylinder from the local gas place (~$44 to exchange for a new tank). I have three tanks and exchange one every two years or so when it gets down to ~1000psig.
Once you make the initial investment to have cylinders cascade in series (so you alway charge from the low tank first), oxygen in the plane is about the cheapest thing you will ever put in it.
Carl
Make the investment to have a charging station in your hangar. Get a group of 3-6 people to each get a cylinder from the local gas place (~$44 to exchange for a new tank). I have three tanks and exchange one every two years or so when it gets down to ~1000psig.
Once you make the initial investment to have cylinders cascade in series (so you alway charge from the low tank first), oxygen in the plane is about the cheapest thing you will ever put in it.
Carl
I have the Mountain High electronic delivery O2 system. I set it to start delivering oxygen at 10,000 feet. I tend to get a headache if I spend much time above 12,000 without O2. I routinely fly my RV-3 between 13,500 and 16,500’ if I’m crossing high terrain or if the winds are favorable. I live at 5,000’ MSL.
newt
Well Known Member
Plenty of folks here with the Mountain High EDS system, at approximately 2 kilodollars.
The alternative is something like an Aerox needle-valve system with Oxymizer cannulas.
When I look at the MH and Aerox websites, they both have charts intended to say how great their systems are, which list expected endurance for each common bottle size at various altitudes.
For example, here's MH: https://www.mhoxygen.com/2016/wp-content/uploads/Cylinder-Duration-Chart-6-2014Rev8md.pdf
And here's Aerox: https://www.aerox.com/portable-oxygen-system-information/
When I compare these, what i see is that for the same height and bottle size, Aerox and MH produce approximately the same endurance.
Now, I know MH has a reputation for using less O2, stretching out the endurance for a given amount of O2. But their own marketing collateral doesn't back that up.
I think the origin of the belief goes back to gliders, where MH systems are pretty common. In a glider you're constantly changing height, and if you use a needle valve system you'll probably need to leave it set to your maximum expected height so you don't have to twist the knob every few minutes, and that'll make it use a lot more gas than an electronic system that effectively twists the knob on your behalf. I completely understand that, and if I had a glider I'd be signing up to the MH system no questions asked.
But in a GA airplane where you take off, climb to altitude, stay there until T.O.D., the advantages of a MH system seem less pronounced.
MH gets O2 into your lungs by squirting it into the tube when you inhale; Aerox gives it to you by flowing it into a baglet under your nose which deflates when you inhale. No matter how you get it, the amount needed to sustain life doesn't change, so they must be giving you about the same quantity, as reflected in their marketing charts.
But the MH system has a battery in a box full of microcontrollers, pressure transducers and solenoid valves. Complex system, complex failure analysis.
If the only real advantage over a needle valve is that it comes on automatically when you reach a pre-set height, is that really worth all that extra complexity and $2k?
(I'm in the market right now. Help me make a decision here.)
- mark
The alternative is something like an Aerox needle-valve system with Oxymizer cannulas.
When I look at the MH and Aerox websites, they both have charts intended to say how great their systems are, which list expected endurance for each common bottle size at various altitudes.
For example, here's MH: https://www.mhoxygen.com/2016/wp-content/uploads/Cylinder-Duration-Chart-6-2014Rev8md.pdf
And here's Aerox: https://www.aerox.com/portable-oxygen-system-information/
When I compare these, what i see is that for the same height and bottle size, Aerox and MH produce approximately the same endurance.
Now, I know MH has a reputation for using less O2, stretching out the endurance for a given amount of O2. But their own marketing collateral doesn't back that up.
I think the origin of the belief goes back to gliders, where MH systems are pretty common. In a glider you're constantly changing height, and if you use a needle valve system you'll probably need to leave it set to your maximum expected height so you don't have to twist the knob every few minutes, and that'll make it use a lot more gas than an electronic system that effectively twists the knob on your behalf. I completely understand that, and if I had a glider I'd be signing up to the MH system no questions asked.
But in a GA airplane where you take off, climb to altitude, stay there until T.O.D., the advantages of a MH system seem less pronounced.
MH gets O2 into your lungs by squirting it into the tube when you inhale; Aerox gives it to you by flowing it into a baglet under your nose which deflates when you inhale. No matter how you get it, the amount needed to sustain life doesn't change, so they must be giving you about the same quantity, as reflected in their marketing charts.
But the MH system has a battery in a box full of microcontrollers, pressure transducers and solenoid valves. Complex system, complex failure analysis.
If the only real advantage over a needle valve is that it comes on automatically when you reach a pre-set height, is that really worth all that extra complexity and $2k?
(I'm in the market right now. Help me make a decision here.)
- mark
Have a look at oxygen concentrators. I use the Inogen G5 and it works great for my mission. Never have to worry about refilling. Runs on battery, charged by ship power.
newt
Well Known Member
I don't think I'm keen on an electrically-dependent life support system. Gas is pretty cheap.
- mark
Richard Connell
Well Known Member
I’ve got a bottle in the RV10.
But I've also flown quite often with a mates concentrator when just 2up.
If I still had my 7 I’d go with a concentrator hands down over a bottle. Smaller, lighter easier all round. Just plug it in and you’re good to go.
You have to keep an eye on your SpO2 either way so I don’t consider it to be any more risky than all the paraphernalia associated with a bottle.
They do chew some power though so you’ll need 5or so spare amps but that should be no problem in the cruise for most.
But I've also flown quite often with a mates concentrator when just 2up.
If I still had my 7 I’d go with a concentrator hands down over a bottle. Smaller, lighter easier all round. Just plug it in and you’re good to go.
You have to keep an eye on your SpO2 either way so I don’t consider it to be any more risky than all the paraphernalia associated with a bottle.
They do chew some power though so you’ll need 5or so spare amps but that should be no problem in the cruise for most.
chopperchops
Active Member
Any idea what altitude the concentrator is ‘useful’ up to?
Richard Connell
Well Known Member
I think it’s something like 2pax to 14k or 1 to 18k.
Don’t they only come with one barb for the tube? Do they come with T to hook up 2 canolas and do you just run it on max setting?
Same thing for me, Even though I am not really drastically affected at 10K to get headache or similar symptoms but I use it since it keeps me more fresh and less tired. With the O2D2, one cylinder goes a long long way.
Small clarification: the function of the ‘re-breather’ bag is to capture the first part of your exhale. This is oxygen rich/low CO2 air that was in your windpipe but never made it to your lungs. You re-breathe it on your next inhale.
Inogen says they are good up to 10k feet. The FAA has approved them for airline cabin use as most cabin pressure is the equivalent of about 8k ft. I use the oxy concentrator up to 10k ft. Above that I open the regulator on the size "D" oxy tank in the baggage compartment.
wirejock
Well Known Member
Contact Jon. He quoted me a G5 2 place pilot package with five year warranty. About $1800
Jon Abbotts | Pure Medical
www.puremedco.com
888.747.7590 Toll Free
Whatever you decide, do some research locally. The local FBO wanted $75 to refill a "D" aviation bottle. Scuba supplies wouldn't even talk about it. Medical is cheap if you can get a prescription. Contact Dr Blue with AOPA. He will write one. Then try and find a medical supply willing to sell without full medical history and insurance even though you probably will pay cash. I finally found a welding supply happy to issue a medical O² bottle(s) with just the prescription. No arguing.
Jon Abbotts | Pure Medical
www.puremedco.com
888.747.7590 Toll Free
Whatever you decide, do some research locally. The local FBO wanted $75 to refill a "D" aviation bottle. Scuba supplies wouldn't even talk about it. Medical is cheap if you can get a prescription. Contact Dr Blue with AOPA. He will write one. Then try and find a medical supply willing to sell without full medical history and insurance even though you probably will pay cash. I finally found a welding supply happy to issue a medical O² bottle(s) with just the prescription. No arguing.
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Or just do what a lot of us do...buy two large O2 tanks and a transfill system and do it yourself. Any gas supply house will swap a used tank for a full one for a very low charge.
All O2 is the same (except lab grade O2, a different beast and not a factor here). So-called "welder's", "medical" and "aviator's breathing" oxygen all comes from the same process with the same specs nowadays.
wirejock
Well Known Member
Yes. I forgot to mention building a "cascade transfill". Problem here is liability rules. Medical O² was easiest solution.
Honestly, the FAA really needs to fix this. We need O² to fly safe. Why not make it easier? Rhetorical of course.
Back to the original question, (for aircrew) supplemental oxygen is required if you are going to be above 12500 for more than 30 minutes. Also required if above 14000 at all.
The Pilot's Handbook of Aeronautical Knowledge "encourages" oxygen above 10000 day and 5000 at night.
Matt McManus
RV7A (sold)
The Pilot's Handbook of Aeronautical Knowledge "encourages" oxygen above 10000 day and 5000 at night.
Matt McManus
RV7A (sold)
You mean hangar lease rules/liability?
For non-commercial aircraft ops like ours, that is, part 91, they don't need to change anything. 91.211 lists requirements for supplemental oxygen for GA. Doesn't say "aviator's breathing oxygen" or "medical" or anything whatsoever about the grade of O2.
Auburntsts
Well Known Member
For me the easiest solution is my local welding supply store. I also get my beer CO2 there too. For some the easiest, although almost guaranteed to be the most expensive, is their FBO.
PilotjohnS
Well Known Member
Well…. I checked in to a welding supply house and they all want a few hundred dollar deposit plus a monthly rental fee for each tank. It quickly will be more than the FBO charges if I fill up monthly.
Just buy them outright. Then have them swap them out when needed. Rental fee???
New big-ass tanks in the 250-300 range, probably 1/2 or so of that for used. The supply house will just swap them out when you bring in the empty tank, anyway, unless you want to pay more to get your new one back. Buy a couple of used and go from there. As long as they've passed DOT hydrostatic testing, you're good to go.
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Warning, thread drift trivia question!
So, when I have a very well prepared pilot and we need to do an hour of ground time for a Flight Review, I ask him to explain why the above statement is not, strictly speaking, correct.
Carl Froehlich
Well Known Member
Yep. Three of us got a tank for ~$240 for the cascade charging station. No rental fee. A $44 charge to exchange an empty for a full tank. It takes a long time to use up a tank.
Carl
This is the rule for unpressurized aircraft. Pressurized aircraft need to wear oxygen when above 10,000 ft cabin altitude (Part 121)
91.211 Supplemental oxygen.
(a) General. No person may operate a civil aircraft of U.S. registry—
(1) At cabin pressure altitudes above 12,500 feet (MSL) up to and including 14,000 feet (MSL) unless the required minimum flight crew is provided with and uses supplemental oxygen for that part of the flight at those altitudes that is of more than 30 minutes duration;
(2) At cabin pressure altitudes above 14,000 feet (MSL) unless the required minimum flight crew is provided with and uses supplemental oxygen during the entire flight time at those altitudes; and
(3) At cabin pressure altitudes above 15,000 feet (MSL) unless each occupant of the aircraft is provided with supplemental oxygen.
Yep. So the correct procedure is to open the alternate static valve (‘cabin’), set the Kolsman window to 29.92 (pressure altitude), then follow the directions. This is actually the physically correct procedure, as it is the partial pressure of oxygen (almost exactly 1/5 of atmospheric pressure) that governs oxygen levels for a person at rest. But as a practical matter, pressure altitude rarely varies significantly from indicated.
Mine runs off an accessory plug but has a 5 hour battery on the unit. No different than the back-up batteries in our Dynon or Garmin EFIS systems.
I found my Inogen Oxygen concentrator on either Craigslist or Offer-up. Keep looking there and you will likely find a used G3 or G4 for about $500-$800. Even if it needs a new scrubber column, they are only about $120. G4 only puts out 3 liters. G3 puts out 5. My doc said to use 1 liter for every 1000 ft above 8,000. So, the G4 works for me. After 10K ft. I go to my Oxy bottle anyway. I love using oxy at anything over 5k. I seriously notice a more rested and alert state at flights end.
I started with the Aerox system. After years of use (6 or 7 years) the o-rings in the quick connects dried out and would leak plus I also had the ball on the flow meter stick to the bottom and not flow any O2. Hitting the flow meter stick against the airplane, I did get it to work. Was the last time I put the portable O2 system in the airplane for a trip without testing it on the ground before a trip. At the time I had issues, it would have been cheaper to just replace with new Aerox parts but I instead decided to spend the money and convert the Aerox tank over to the Mountain High stuff. That was two decades ago that I converted and the Mountain High stuff is still working great.
What ever O2 system you have or decide to get, it should be tested regularly just like everything else necessary for safe flight.
Hi Mickey,
I would like to know about your experience using the Inogen concentrator. For example, my cross-country mission is cruising at 12,500ft for a couple of 2-hour legs per day. Can the battery unit on the Inogen support a four-hour operation?
Thanks.
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RV8JD
Well Known Member
And keep up with the manufacturer's recommended regular maintenance. For example, note this from Mountain High's maintenance FAQ:
Q. I have one of your portable MH-EDS PULSE DEMAND™ units. It seems to be operating just fine, should I
send it in for any type of routine service or testing?
A. Yes. Even though your pulse demand unit will generally let you know if there is a problem and has been designed
to be relatively maintenance free except for batteries, it should be sent in on a regular basis for performance
inspection and service. This includes the in-line or screw–on regulator you use with the EDS. Think of it like
performing an annual inspection on your aircraft.
Q. How often does MH recommend this service be done?
A. This service program has been derived from usage and servicing data acquired over the last 20 years that the technology has been in production and fielded. From this, Mountain High has decided on a routine service program that should be accomplished once every two years, (biennial). This must include the remote pressure regulator you are currently using with the EDS unit(s). We can only service MH manufactured regulators.
Q. What is done to my EDS unit and regulator when I send them in for service.
A. From time to time we make engineering improvements during our production. These improvements may include changes to hardware or firmware or both. This is our way of passing on our latest improvements to you. Also routine service parts such as seals, seats, O-rings and filters are inspected and replaced. Your EDS unit(s) and regulator(s) are then thoroughly inspected and tested on our ATP test set to ensure they are operating to specified standards. This will help to ensure your system is operating properly and upgraded to the latest specifications.
Q. How much does it cost me?
A. Pulse Demand service is US $125.00. Pressure Regulator service is $75.00. This includes all firmware and hardware upgrades. Routine service parts are also included. Any other parts replaced due to damage or field use would be subject to an additional charge. Shipping is additional.
Q. How long should I expect this service to take?
A. Once we receive your unit, in-house turn around time is generally (7) to (10) working days.
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I have been using Inogen for few years. started with G4 and for the past year to a G5. I frequently do 3 hr flights, I have the bigger battery I can do a round trip if I use setting 3. I use about 30 to 40% of the battery on those trips. I carry the cig plug cord but never used it. My pulse oximeter is usually 95 to 96. I cruise usually between 11.5K to 13.5k. if I go to 15.5 I put on setting 4.
I love it, never have to worry about having enough air for the trip or not being able to get it refilled on a Sunday or something.
I have the G5 with the big battery, but keep my connected to ship power all the time. So I've never tested the endurance. My flights at 12k and above are typically shorter, around an hour. Saturation on the Inogen o2 is always above 95, typically 98 or 99 on either setting 3 or 4.
