Basics for on-board O2 use

[ZamF16]

I have had my Bravo for a year now, but still have not gotten it up to altitude as I don't have the masks/fittings for my O2 system. Frankly, I cannot tell what I need to buy. From what I can tell I need the Scott fitting to plug into the aircraft system, and a mask for above 18k', but do I also need a regulator of some type, or do I connect the masks directly to the aircraft system?

Looking for some advice/insight.

Zam

[carqwik]

You can plug in directly to the oxy outlets...but you will use the oxygen quickly. I first used cannulas straight to the plug but the oxygen depletes quickly. Switched to the Oxysaver cannulas and that cuts the O2 use dramatically. They have a very simple metering device...useful up to FL180. I think it is a Scott fitting for the Mooneys. Btw, your Bravo is about 12-15 kts faster in the high teens then at 12k.

[rainman]

I agree with carqwik, the "on-demand" type canula will really extend the useful time of each full tank. Sky-Ox is another company I found on the net with supplies. They have pictures of the products/plugs/connectors. The extra cost for "on-demand" is more than offset by the reduced hassle of having to get a refill. As I have recommended many times on this forum, be sure to use a pulse oximeter also. You may find that you need oxygen below 12.5 and if your oxygenation is below 90% put it on. Ray

[AndyFromCB]

http://preciseflight.com/general-aviation/shop/kit/single-a5-breathing-station-beech-mooney-piper/

A complete kit, including mask, cannula and flowmeter. It's what I purchased. Between the conserving cannula and a flowmeter, your oxygen supply will last quite a while.

[Awful_Charlie]

Zam

You have asked he nearly impossible question, without knowing a bunch more you might as well ask 'which is better, diesel or petrol' ;-)

I'm in Yurop, so things may a bit different, but there is a load of guff to consider, fortunately most of it is relative pennies, unless you happen to have a 'bad' profile ;-)

I rent a big cylinder, that costs about USD70 a year, each fill is about another USD50. I could go to a local maintenance facility (an hours flight each way) that would charge me USD100-120 for a fill, but I can get nearly 3 full charges out of a full rental cylinder, therefore anything more than a fill every year means I should rent the bottle. Cannulas are USD20 a pop, and although they can be cleaned, do you fancy telling you pax that they've got to stuff a cunnula up their nose which might have the previous pax's boogers still on it? If you get into masks (you need to have your own at least), with a mic you are looking at USD400 per place before you add the fittings.

Look at the POH Fig 7-13 to determine how much oxygen you need to carry: if you do a trip between base and somewhere else and then return, that needs less than capacity, with the same pax each time, then you are probably best off with a DIY (get your own cylinder and filling loop) approach. If oxysavers mean this is what you need to get there, then spend on those.

At the other extreme would be to have cheap fills wherever you go, with different pax each time, in which case get the cheap non-saver canulas for all and sundry.

The Bravo loves altitude, and it also gives you the weather avoidance when you need it. Even if I don't expect to need it, I still carry a cannula and a mask when I go away for the weekend, that way if the return leg demands FL200+ I am covered and have the kit.

As for what you need, when you've worked through the above:

-Cannula, and/or Oxysaver cannula with a flowmeter

-Mask

-Oximeter

The hose to get from whatever to the cabin point

A connector for the cabin point. This one is a bit difficult. Note that the manual specifies a green band connector, which is required for a mask without a flow valve. If using Oxysaver cannulas, with a fit person (fit as in health, not appearance!) you might get away with a red or a gold one, but you need to have the oximeter and understand what the bands mean before you go down that route. Consequently, non-Green band connectors are not much use for unknown pax, but at USD100 a pop, you probably don't want to be getting 4 of each colour!

Don't forget that the standard Bravo cylinder has an altitude compensating regulator that increases the output pressure with decreasing ambient. This regulator should be tested every three years, and overhauled every six (PITA that is, as it doesn't fit with the cylinder hydrostat test), but does at least mean that if you have verified the results with a flowmeter and oximeter, you might be able to dispense with the flowmeter and use one of the lesser costing connectors.

hth

Ben

[AndyFromCB]

Ben,

What are the connectors you are talking about? Do they function as restrictors for the built in altitude compensating regulator? If so, why not just buy a flow meter like the one includes in the kit I linked to above?

Andy

[kortopates]

Andy is right on, skip the different connectors and go with the A5 flowmeter from Precise with the kit he recommended - its a great choice. PreciuseFlight makes the very best flow meter available on the market. Its worth every penny for the amount of oxygen it will save over just using the appropriate restricted connector. (Honestly, i didn't think anyone used those anymore given how much more effective a good flow meter is. The mask that comes in the kit is pretty worthless, except for a back seat passenger. Eventually you'll need to get a real mask with built in microphone which are quite expensive.

You've gotten good advice about getting a pulse oximeter. We've been using one since Nonin introduced their first affordable yet reliable finger pulse oximeter for the aviation market about a decade ago. These days there are all kinds available for cheap. But before you buy a cheap one, suggest you review Nonin's little marketting video providing a side by side comparison of its competition - it can be an eye opener. http://www.onyxvantage.com/why-onyx.htm?cont=NA&lang=1 I have no relationship with them, just a very satisfied customer that's got about 10 years on the original Flightstat unit and it's still going strong. Aeromedix is one discounted source for them as well as some other brands.http://www.aeromedix.com/Nonin-9590-Onyx-Vantage-Fingertip-Pulse-Oximeter.html Most of the literature suggest you'll want to adjust your O2 flow meter rate to keep a SP02 of 92% minimum. If your unable to keep at 92% with a cannula at some threshold altitude (even with the flow meter cranked up), then you'll just need to use a good aviation mask for that altitude and above; even though the regs allow use of the cannula to 18K. Or you could find as my wife did that she has no problem maintaining 92% upto 21K with a cannula (although she is well adapted with a long history of high altitude climbing). Regardless though, if you are going to venture into the flight levels, I suggest you procure a small handheld emergency backup device in case you have an unexpected failure - you never know.

Since you've never used your builtin 02 system, perhaps the first thing you want to check is to see if your tank is still airworthy for filling i.e., its not due for hydrostatic testing or the cylinder isn't beyond its age life and the tank still has at least 50psi. These limits vary by cylinder type, for example light weight cylinders (DOT 3HT) require hydrostatic testing every 3 years as long as the pressure of cylinder has not dropped below 50 psi; otherwise it needs to be inspected. ( A heavier DOT 3AA cylinder goes 5 yrs between hydrostatic tests.)

As Ben pointed out though, you're loosing a lot of performance flying a turbocharged Mooney down low. So get yourself set up and take advantage of the less crowded and smoother air above and really see some impressive groundspeeds!

[ZamF16]

All,

Thanks very much for the info. I have the heavier DOT 3AA cylinder and it was inspected last year right before I purchased the aircraft. It had 1700 psi on the gauge when I bought my Mooney and still does today. I think I will go with the complete kit: Mask, Cannula, and flowmeter. Again, thanks for all the advice.

Zam

[ZamF16]

One last question...does the O2 flow freely out of all four ports when the O2 is turned on at the console, or does it only flow out ports with the Scott fitting attached?

Zam

[Awful_Charlie]

The precise flight flowmeters Andy linked to look good - I've got one which is a combined plug in adapter and adjuster in one, and that is a sharp little devil that just loves to take chunks out of your scalp if you get too near it. Otherwise, I don't like flow regulators for small children (who want to fiddle), and when three or four up, the place is already starting to get like a bad day in a spaghetti factory with headsets, oxygen, MP3 players and cameras - adding longer pipes (you have to hold the flow meter vertical to get a reading) doesn't help that.

The outlets don't flow oxygen when nothing is plugged in (or they shouldn't, but leaks are not unheard of). A test on that would be to leave the control knob on, and see if the pressure reduces over several hours, it shouldn't drop at all over a week, but be prepared to get a fill if it does leak!

[AndyFromCB]

Charlie,

You must be taller than me or sit up higher in the seat. Mine are exactly the same and my scalp still seems to be in one piece.

Zam,

The oxygen should not flow without being plugged into, I generally leave my oxygen on all the time, this way when I pre-fly, I can see if there is any leaks. None so far. As to the oxygen tank, if it's the kevlar type, it needs be replaced every 15 years as well. I have a PMA source, much easier than dealing with Zodiak. Aerox now has them PMAd as well. Turbine Rotables will overhaul your regulator for about $700 as well, once again, much easier than dealing with Zodiak, 3 day turn around. I don't know about European Zodiak but here in US, I had a new tank from CA at my door step and a overhauled regulator shipped back and forth to Kansas before one of Zodiak's reps called me back. All tanks are actually made by one little company in US and before they get an FAA part # stamped on them, they cost $300.

Being a European ex-pat living in America, I understand that nothing happens in Europe in August (or Jan-Dec if dealing with Spaniards, French or Polish) but I was dealing with a crew from Georgia, USA and they were the most miserable bunch of people I've ever dealt with.

As to what I did with my old tank, well, I'm turning into a giant potato gun ;-)

As to cannulas, if you bump up the flow to mask level and are somewhat flexible with the "regulations", you can easily wear them to FL230, I know quite a few sailplane pilots who do and still maintain as good oxygen saturation as with a mask. There is no reason to buy the expensive but most of all, uncomfortable mask. Cannulas work just fine.

Andy

[thinwing]

My tank is coming up for replacement..who was your pma source??I have a 105 cu ft kevlar tank..kpc

[AndyFromCB]

My tank is coming up for replacement..who was your pma source??I have a 105 cu ft kevlar tank..kpc

You can deal with Zodiak/Avox, get a bunch of run around, finally speak to somebody 3 weeks later and then maybe get your system serviced in 3 months

or

http://www.hrd-aerosystems.com, part number is H21507-04, about $1700. The original part number is 21507-04, this is a PMA bottle, identical to the Scott/Zodiak system as the oxygen bottle is actually made by SCI for medical purposes. The part is also used in Boeing jets so they always seem to have fresh bottles at HRD.

As to your regulator, http://www.turbinerotables.com/ will overhaul for about $700 with a new boss fitting, it was a 3 day turnaround for me. Ask for Mark Mertes, a pleasure to deal with. They want your business unlike Zodiak.

[Awful_Charlie]

Guess astelmaszek has a problem with Zodiac

See http://www.mooneyspace.com/index.php?/topic/4004-bravo-oxygen-2/#entry50096 - Zodiac UK did me a regulator overhaul (including parts) *AND* a cylinder hydrostat test for about 300GBP, with a turnaround of a few days (the cylinder has to stay pressurised for 24 hours IIRC) so cheaper than the USD700, but shipping might take away the advantage in time and money. Contact details are in the linked post

Ben

[AndyFromCB]

Ben,

I don't know about Zodiak Europe, they might be great, but here in the US, their customer service is the worst I've ever dealt with. A local guy called me back right away but he could only point me in the right direction. At that point, it was 3 months of phone tag, then I threw in the towel. Then my mechanic tried and had the same issues of getting blown off. Finally, a guy called us back from Georgia, 3 weeks after we already got the bottle and regulator back from the above mentioned companies.

Second of all, Zodiak does not actually manufacture the bottle. It is made by a company called SCI, they just put a label on it with a part number. When I finally got a call back, their price for the bottle was $2000. Same bottle from HRD, $1700.

Andy

[ZamF16]

My tank is coming up for replacement..who was your pma source??I have a 105 cu ft kevlar tank..kpc

I have not had to replace or inspect the tank yet. It was inspected just prior to my purchase last year, and is good for another 4 years. Sorry, no advice to offer.

-Zam

[ZamF16]

All,

I purchased the A5 Flowmeter kit and over 4 days flew 3200 miles from San Antonio to August, to Dayton, to Colorado Springs, and back to San Antonio. Flew in the low FLs all the way. What a joy! With the Flowmeters, mangaged to travel with three adults the entire trip on one tank of O2. Thanks for all the advice.

Zam

[jlunseth]

I am in the flight levels quite a bit, and I have the precise flight equipment. I would also highly recommend the oximeter. In my experience, and with many different passengers, the scale on the precise flight flowmeter that is for use with the oxymizer cannulas is not very accurate and results in mild hypoxia - in the high 80% range when you should definitely be in the 90's. The oximeter will help you set the flow correctly.

If you go above FL180 you should use a mask. I have a mask with a mike. I have noticed the O2 savings with a mask is significant over a cannula, although the cannula is more convenient.

[thinwing]

I have had the opposite experience re mask vs oxymizer cannula....02 use is about twice with the mask ....oxygenation at all altitudes is better with the mask...I am using blue silacone scott mask with mic..it is fairly comfortable with oxygenation levels averaging 95% up to 23k I have flown...kpc

[carusoam]

Nice data point... 23kft, 95% 02, Scott mask

KPC,

Did you say the mask uses more O2 under the same conditions as the cannula? I think I missed some details.

I'm not an O2 user yet... Getting closer...

Best regards,

-a-

[thinwing]

My mask definitely uses more o2 than cannula....I had a chance to compare o2 use on a flight to Montana...at 17k I was having trouble hitting 90% even with the 02 turned up to the top of the cannula scale on the left side of oxymizer ball guage.(probably due to allergies that day)Switched to the mask and set it for 17k on the right side of scale and started mouth breathing...o2 use shotup to about 200 ibs per hour vs about 100 with the mask.O2 saturation peaked at 97% though...only down side was hoarse throat from all the dry O2 mouth breathing...kpc

[Top Heavy]

Do you need a flow meter with the oxymiser cannula?

[Marauder]

Do you need a flow meter with the oxymiser cannula?

No but it makes it much easier to set the flow for the altitude you are at (as a starting point). I set it and then use the meter to figure out my "today's" saturation level and adjust the flow a bit.

The needle valve can be a bit sensitive to adjust.

[Awful_Charlie]

Do you need a flow meter with the oxymiser cannula?

 

I would say you *do* need a flow meter, or there's no point in getting an Oxysaver/oxymiser - just go for the plain cannula (and put a few $ in the CB club tin, but you'll spend it on  fills later)

 

I find the mask gets through 3 or 4 times the O2 as the oxysaver, but some of that is due to the higher altitude

[jlunseth]

I haven't seen the one major advantage of a flow meter mentioned, and that is that you can look at it and know that you have flow.  The little ball is up.  You can sometimes feel flow with a cannula, maybe maybe not, but you can't feel flow at all with a mask, so no way to know until symptoms start.  I have an oximeter and used to use it quite alot, but don't bother anymore because I know what the flowmeter will do, and so long as the ball is up where it is supposed to be I am good.

 

The weather advantages of going high are major.  I flew a 3 1/2 hour Angel Flight positioning flight to western Neb. last weekend.  Cloud deck got higher and higher as I went west and there was possible ice in the clouds.  I wound up going from 8k to FL200 to get over the tops.  Just no issues at all and it was nice and sunny up there.