Primarily for general aviation discussion, but other aviation topics are also welcome.
User avatar
By marioair
#1712170
I am thinking of getting a portable setup. Leaning towards the Mountain High kit but after the collective wisdom. Here are my “requirements”

  • Most likely either 1 or 2 up but would like option of 4 Paxs if possible, or option to “upgrade” in the future
  • Less than 18,000feet usage (non turbo)
  • Unlikely to be used regularly or for long periods (max 2 hours per leg) and probably a few times a year max
  • Needs to be highly portable as can’t leave in aircraft

To this end can you recommend

  • Most portable/smallest possible size cylinder that would be appropriate
  • Whether I should get constant flow or demand flow system or could I upgrade from former to latter in stages - is their cost benefit of doing it all in one go
  • How long would constant flow v demand flow last in hours, say at 10,000 feet
  • Where can I get it re-filled (I live in SE London) and how much does this cost
  • Is anyone interested in sharing?
  • Are there any other on going running costs involved?
User avatar
By ls8pilot
#1712174
Mountain High kit is very popular in the gliding community.

With the EDS pulse regulators a small bottle will last several hours (much more efficient than simple constant flow). When I flew in Minden we used an EDS regulator with a nasal cannula - they considered these good up to18000ft. The EDS regulator automatically adjusts the amount delivered as you climb/descend.

Lots of options to configure a set-up, worth a phone call to someone like Navboys for advice.
User avatar
By Flyin'Dutch'
#1712188
I have a MH set for sale.

PM me if you want more details.
User avatar
By Ben Twings
#1712211
The MH demand system is a bit of an overkill for your situation.

With an oxy-miser type cannula 0.5 lpm per person is good for 15000'. That keeps my saturation in the mid 90s.
A 20 cu.ft bottle would give you ~1000 minutes at that rate for one user or 250 minutes for 4 users.

The most expensive bit of the kit is the regulator. I use the skyox 2-place one. It will supply the same rate to one or both lines that are attached to the bayonet fittings.

Cylinders should be hydro tested every five years, but that is relatively inexpensive and plenty of places do it.

I get mine filled from a hangar neighbour who has a couple of welding bottles and a trans-fill adapter. A dive shop that does oxygen mixes should be able to do it if they have the correct (probably CGA540) fittings.

My system is quite portable and weighs about 8kg.

A cheap and good investment is a pulse oxymeter. Monitor saturation regularly and keep it above 90%, preferably mid 90s.
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User avatar
By TheDealer
#1712225
I have used most of the portable systems - need to get to 25,000 ft to ensure regulatory compliance over the Atlantic and get max range out of a Caravan!

The Mountain High kit is without a doubt the best out there, the EDS on demand system works very well but is only two place as far as I am aware although you could use a double output regulator and use twin EDS boxes.......overkill for your situation anyway....go to the MH website and they have published bottle endurance figures for both free flow and EDS scenarios at various altitudes.....work out which bottle size works for you and let me know, I have a dozen or so in the hangar, generally only used once for an Atlantic crossing, carry bags etc......

Cheers

TD
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User avatar
By marioair
#1712234
@TheDealer thanks!

What's involved in refilling and maintenance and is there a "lifetime/use by" on the air. My gut feel is to go for the smallest possible size to give me about 4 hours for two people.

I'd be tempted to start with the constant flow sytem and see how I get on it, if its cheaper. However can I "upgrade" to the EDS system later on?

@Ben Twings mentioned the oxymiser cannulas but I think you can get these from mountain high as well. The skyox looks like a neater package in terms of the regulator and flowgauge in one, whereas the MH system has seperate flow meters which need to be "hung" somewhere to work by the looks of it?
User avatar
By TheDealer
#1712239
Interesting question.....don’t think there is a “use by” date for oxygen......the cylinders don’t get purged on refill on either portable or installed systems?

I have a SkyOx bottle and regulator in the hangar, sure it needs a 5 year test, will send you a pic later in the week if you are interested in it.

Cheers
TD
User avatar
By TheDealer
#1712240
Filling - MH sell an adapter to fit their bottles and converts the filler to standard aircraft size/thread which appears to be fairly universal and Oxygen is now Oxygen so fill from the hangar supply, welding bottles or just about anywhere else.

Bottle maintenance - 5 year inspection similar to a Scuba tank.
User avatar
By marioair
#1712255
Seems like flow adjustment on the syox is on the regulator, whereas for the MH it's a seperate unit? where do you put it if using the MH one?
By cockney steve
#1712293
I know nothing about aircraft oxy systems, but I do know that BOC have gas and welding-supplies depots all over the country and they also supply LOX to bulk tank systems (hospitals) and more importantly to high-flyers, they supply very light portable Oxy- cylinders made of carbon-fibre composite
They have the usual "idiot-proof" medical-gas fittings, meant to prevent connection to the wrong line in multi-gas setups (anaesthesia) Ordinary gas- bottles can be rented (yearly contract , IIRC, but premature return elicits a refund for unused whole months. There is also sometimes a deposit and a transaction-charge applies, whether returning one empty or buying a full pallet of cylinders. see also Air Products, the other major UK distributor of non-fuel gases.
User avatar
By TheDealer
#1712321
MH also do Carbon cylinders and Kevlar wrapped affairs that take a lot more pressure.......I used one of these with the EDS system to take a Caravan from UK to the Maldives.....needed to go to 20,000ft to get the range and there was nowhere practical to get a refill after Cyprus....great kit.