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Looking for help setting up O2 with my jet mask

AX-O

Well Known Member
All,
I am trying to figure out how to integrate my MBU-12 O2 mask into my oxygen system in the RV. I already use the standard HGU-68 helmet but would also like to implement the mask/Comm. If you have done this or know of a place that I can look into, I would appreciate it. Forced O2 not required.

Thank you for any help.
 
Perhaps check with Gibson and Barns? Things like the exhalation valves and such my not work without a pressurized system.
 
The MBU-12 is designed for a demand oxygen system (like a scuba mask), not a constant flow system as most GA aircraft use. Demand systems use a LOT of oxygen, up to 25 litres/ minute compared to 2-4 on a constant flow system, and less on a pulsed system.

It'd be a major project to run this mask as a CF system, particularly testing/ verification.
 
You might want to give the guys over at Human Systems near your facility a call.

FlightHelmet.com has a lot of parts ant they might be able to help. You can also pick up that g suit and ejection seat that you have always wanted.

http://www.flighthelmet.com/

-larosta
 
I have interest in doing this as well although it's with an MS-20001 and also an A-14. These are Korean War and WWII masks.

The valves are no longer made for these masks and I don't trust old ones. Neither are the metal connectors made. So any system would have to circumvent that whole setup. Plus it uses too much O2 as people say.

So what I was wondering is:

What would be the available O2 at your nose if you ran a modern small flexible hose up through the large mask hose and then placed the cannula across the mask roughly under your nose?

Would you get enough O2? The two outlets of the cannula are not necessarily positioned where they would be if you wore it as designed - maybe an inch away. But then you have the enclosure of the mask to trap unused O2.

But then you are also exhaling through the mask which blows both exhalent and unused O2 out the mask. You can remove the valves so that there's a clear path out.
 
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Someone who will know

Elliot Seguin would know. He uses the set up you are looking for. Don't have his contact info He hangs around Mojave. Share what you find out

kai
 
Maybe someone with a pulse oximeter could test nasal cannula vs mask with nasal cannula in it as described above.

I suspect it will work better than nasal cannula alone.
 
Maybe someone with a pulse oximeter could test nasal cannula vs mask with nasal cannula in it as described above.

I suspect it will work better than nasal cannula alone.

I've got a PO. I've been trying to think of a suitable ground and flight test.

Take PO reading without mask

Put mask on, turn on O2, Take PO readings a (?) intervals.

If that's safe then I would take it up to (?) feet and run the same test.
 
Check with Col. J Nelson, retired.

watch


You might have met him at Reno.
 
IIRC, I think Coach Nelson just had the tube to open air that year at Reno. Not sure tho. He's got a place at L00 AC, and Cougar can get in touch with him.

Jeff Lavelle does have a setup that may work for you. His regulator sits in his front seat in Sport 39. Might be a bit large for a 4, but it might work.

Will text you his contact info Axel.

Cheers,
Bob

Check with Col. J Nelson, retired.

watch


You might have met him at Reno.
 
Okay, thinking outside the box here... How about just running the finer O2 lines that you typically find in GA O2 systems up the Jet mask hose, and fitting a cannula into the jet mask somehow, so it fits into your nose when the mask is on?

Heck, someone could even 3D print a custom cannula to fit into the front of the jet mask...

That would allow you to use an O2-saving GA system, *and* look like a fighter jock... :)
 
It would probably work Rob...as long as it didn't get too squished...or tickle too much! ;)

I know one reason Jeff and other racers go for the full-on mask system is to be able to to to 100% O2 and seal out smoke, should that get in the cockpit.

I'll see if I can get some pics of his race system...its nice!

Cheers,
Bob


Okay, thinking outside the box here... How about just running the finer O2 lines that you typically find in GA O2 systems up the Jet mask hose, and fitting a cannula into the jet mask somehow, so it fits into your nose when the mask is on?

Heck, someone could even 3D print a custom cannula to fit into the front of the jet mask...

That would allow you to use an O2-saving GA system, *and* look like a fighter jock... :)
 
Okay, thinking outside the box here... How about just running the finer O2 lines that you typically find in GA O2 systems up the Jet mask hose, and fitting a cannula into the jet mask somehow, so it fits into your nose when the mask is on?

Heck, someone could even 3D print a custom cannula to fit into the front of the jet mask...

That would allow you to use an O2-saving GA system, *and* look like a fighter jock... :)

I suggested that, in this thread, a few posts before this one:

"What would be the available O2 at your nose if you ran a modern small flexible hose up through the large mask hose and then placed the cannula across the mask roughly under your nose?"


And then I posed questions about the idea such as:

"Would you get enough O2? The two outlets of the cannula are not necessarily positioned where they would be if you wore it as designed - maybe an inch away. But then you have the enclosure of the mask to trap unused O2.

But then you are also exhaling through the mask which blows both exhalent and unused O2 out the mask. You can remove the valves so that there's a clear path out."

And then I proposed a couple of ground and an air test.

"Take PO reading without mask

Put mask on, turn on O2, Take PO readings a (?) intervals.

If that's safe then I would take it up to (?) feet and run the same test."

Maybe there are better tests to be made.

This system would not keep smoke out unless the larger diameter tube was closed off, and you kept the check vales in place.
 
Scott 28000

I used a Scott /AVOX 28000 diluter/demand regulator pulled from a 727 and yellow tagged. I think the aircraft maintenance company I bought it from is out of business, but they should still be fairly easy to find. The Glider guys use a seat mounted version, but I wanted the panel mount. I got a custom tank reegulator from Mountain High to produce the 55psi the diluter/demand regulator needs. They were great to work with.

If you have the helmet and mask, you've already got the expensive bits. The diluter/demand regulator was $400 and the Mountain High guys charged me the same price for my custom tank reg as the stock GA ones. $195 at the time, but that was a number of years ago. Also, I got the comm adapters from flighthelmets.com which was already mentioned.
 
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Axel - a couple of ways you can go here, depending on what regulators you can find in good, operating condition.

Here's what Elliot uses: https://m.youtube.com/watch?feature=youtu.be&v=a-lceaOL2E8

Most Military regs are second stages that require a 50 psi input pressure. You can find first stages that mount directly to a CGA 540 bottle for about $100 (I have one from Meret). Teflon lines, steel braided hose (AN4) and fittings is plenty for the expected intermediate pressure.

For a second stage, if you want to go REALLY compact, a CRU79/P fits essentially on the end of your mask hose (you might need to find/buildan adapter if you don't want to hack up the end of your hose - check Flighthelmets.com), but it is wasteful (if endurance is important) since it is a pressure-demand reg with no way to switch it off. A Diluter Demand unit (Liek the Scott/AVOX 28000 panel mount) is more efficient, but a little problematic to find space for in a tandem RV panel, You can use it as a portable, but it will be rattling around on the floorboards.

I have both a CRU79 and a 28000 that I can use as the situation requires. You'll need to do some searching (or lathing) for necessary adapters to build the system. Fun to play with (I built SCUBA systems and dive shop air systems in my youth) but make sure to observe good clean oxygen protocols for safety reasons (don't blow up your shop....).

Paul
 
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