The POH for LS8 recommends a 3-4 L cylinder for the built-in mounting sleeve. I've not found any 100mm cylinders for sale in the US.

Some of the EU glider accessory retailers sell 2L 100mm AL cylinders. Using a Mountain High pulse system, this provides enough time for me. How well does a 2L cylinder fit in the LS8?

I'm wondering if a 2L cylinder also makes the cockpit a little less cramped.

On Monday, February 20, 2023 at 10:14:43 AM UTC-7, son_of_flubber wrote:
> The POH for LS8 recommends a 3-4 L cylinder for the built-in mounting sleeve. I've not found any 100mm cylinders for sale in the US.
>
> Some of the EU glider accessory retailers sell 2L 100mm AL cylinders. Using a Mountain High pulse system, this provides enough time for me. How well does a 2L cylinder fit in the LS8?
>
> I'm wondering if a 2L cylinder also makes the cockpit a little less cramped.

Most cylinders are rated at the volume of the compressed gas, meaning 180 liters, 248 liters, 415 liters and so on. It is difficult to correlate that to the physical volume of the cylinder you plan to use without the dimensions (diameter, length, etc.)

Unfortunately, most of the European glider manufacturers only provided for 100 mm diameter steel cylinders, which as you have discovered, are difficult to find. Nerwer Aluminum cylinders have also been in short supply lately. I was recently quoted a 52-week delivery by a normally reliable source, and it took nearly five months to get one from Mountain High. I haven't had to order any recently, so I am not sure if the supply chain has caught up.

The most significant problem with your situation is that the steel 100 mm cylinders are the only thing that will fit in the sleeve. Correspondingly sized aluminum cylinders are all 111 mm in diameter. The only other option is the KF-011 cylinder, which is a Kevlar fiber-wrapped aluminum cylinder. It is 93 mm in diameter and holds 311 liters at 1850 psi. Unfortunately, the fiber wrapped cylinders (Silica, Kevlar and Carbon) all have a finite life of 15 years, after which they are no longer certifiable. The Kevlar and Carbon fiber wrapped cylinders are lighter, but MUCH more expensive.

If it is available, the AL-180 cylinder from Mountain High may be an option.. It is only 81 mm diameter and 300 mm in length. The capacity is 165 liters at 2216 psi, which is enough for 3.8 hours at 18,000 ft MSM when using the MH EDS system. I consider this to be a minimal supply and is insufficient for high desert flying or high-altitude wave flights.

Oxygen is fuel for your brain. Don't run out. It's not like running out of gasoline by the side of the highway.

On Monday, February 20, 2023 at 10:14:43 AM UTC-7, son_of_flubber wrote:
> The POH for LS8 recommends a 3-4 L cylinder for the built-in mounting sleeve. I've not found any 100mm cylinders for sale in the US.
>
> Some of the EU glider accessory retailers sell 2L 100mm AL cylinders. Using a Mountain High pulse system, this provides enough time for me. How well does a 2L cylinder fit in the LS8?
>
> I'm wondering if a 2L cylinder also makes the cockpit a little less cramped.

Most cylinders are rated at the volume of the compressed gas, meaning 180 liters, 248 liters, 415 liters and so on. It is difficult to correlate that to the physical volume of the cylinder you plan to use without the dimensions (diameter, length, etc.)

Unfortunately, most of the European glider manufacturers only provided for 100 mm diameter steel cylinders, which as you have discovered, are difficult to find. Newer aluminum cylinders have also been in short supply lately. I was recently quoted a 52-week delivery by a normally reliable source, and it took nearly five months to get one from Mountain High. I haven't had to order any recently, so I am not sure if the supply chain has caught up.

The most significant problem with your situation is that the steel 100 mm cylinders are the only thing that will fit in the sleeve. Correspondingly sized aluminum cylinders are all 111 mm in diameter. The only other option is the KF-011 cylinder, which is a Kevlar fiber-wrapped aluminum cylinder. It is 93 mm in diameter and holds 311 liters at 1850 psi. Unfortunately, the fiber wrapped cylinders (Silica, Kevlar and Carbon) all have a finite life of 15 years, after which they are no longer certifiable. The Kevlar and Carbon fiber wrapped cylinders are lighter, but MUCH more expensive.

If it is available, the AL-180 cylinder from Mountain High may be an option.. It is only 81 mm diameter and 300 mm in length. The capacity is 165 liters at 2216 psi, which is enough for 3.8 hours at 18,000 ft MSL when using the MH EDS system. I consider this to be a minimal supply and is insufficient for high desert flying or high-altitude wave flights.

Oxygen is fuel for your brain. Don't run out. It's not like running out of gasoline by the side of the highway.

This has been a recurring topic in the ASW 20 & 27 newsgroups. Some have resorted to digging through older cylinders to find compatible diameters at whichever supplier would allow them to do so. Thank you, John Murray, for finding a cylinder for my 27.

Are suitable cylinders available in Europe?

If you do have a cylinder in the new materials, do watch you don't overfill it.

On Monday, February 20, 2023 at 6:45:02 PM UTC-5, George Haeh wrote:
> This has been a recurring topic in the ASW 20 & 27 newsgroups. Some have resorted to digging through older cylinders to find compatible diameters at whichever supplier would allow them to do so. Thank you, John Murray, for finding a cylinder for my 27.
>
> Are suitable cylinders available in Europe?
>
> If you do have a cylinder in the new materials, do watch you don't overfill it.

http://glider-equipment.nl/catalog/product_info.php/oxygen-o2cylinder-steel-80030-p-1662 179EUR
https://millenair.eu/product/oxygen-bottle-light-steel-3l/ 199EUR

European tanks are available... if you're thinking of going this route you might also look into refilling your own tank.

Doug

On Monday, February 20, 2023 at 8:50:16 PM UTC-6, Dan Daly wrote:
> On Monday, February 20, 2023 at 6:45:02 PM UTC-5, George Haeh wrote:
> > This has been a recurring topic in the ASW 20 & 27 newsgroups. Some have resorted to digging through older cylinders to find compatible diameters at whichever supplier would allow them to do so. Thank you, John Murray, for finding a cylinder for my 27.
> >
> > Are suitable cylinders available in Europe?
> >
> > If you do have a cylinder in the new materials, do watch you don't overfill it.
> http://glider-equipment.nl/catalog/product_info.php/oxygen-o2cylinder-steel-80030-p-1662 179EUR
> https://millenair.eu/product/oxygen-bottle-light-steel-3l/ 199EUR

On Monday, February 20, 2023 at 9:14:43 AM UTC-8, son_of_flubber wrote:
> The POH for LS8 recommends a 3-4 L cylinder for the built-in mounting sleeve. I've not found any 100mm cylinders for sale in the US.
>
> Some of the EU glider accessory retailers sell 2L 100mm AL cylinders. Using a Mountain High pulse system, this provides enough time for me. How well does a 2L cylinder fit in the LS8?
>
> I'm wondering if a 2L cylinder also makes the cockpit a little less cramped.
Its been over 15 years, but I was able to find a used steel cylinder for my LS8 at Norco.

New cylinders are usually sold with a valve and filled with slight positive pressure O2 to prevent contamination.
The EU retailer that I spoke with told me that hazardous materials shipping regulations required him to remove the valve prior to shipping. A visual inspection needs to be possible. I guess that this is maybe because O2 cylinders make great bombs and you can't look inside them with X-rays.

With valve removed, the cylinder is subject to contamination, condensation etc. (which is why it is sold with a valve and positive pressure in the first place). So when the cylinder arrives in US, I guess I would have the cylinder hydrotested and probably replace the DIN-477 Euro-Norm valve with a CGA-540 Standard North American (to facilitate refills).

I wonder if that European tank will have a DOT stamp on it....

Doug

On Tuesday, February 21, 2023 at 9:59:40 AM UTC-6, son_of_flubber wrote:
> New cylinders are usually sold with a valve and filled with slight positive pressure O2 to prevent contamination.
> The EU retailer that I spoke with told me that hazardous materials shipping regulations required him to remove the valve prior to shipping. A visual inspection needs to be possible. I guess that this is maybe because O2 cylinders make great bombs and you can't look inside them with X-rays.
>
> With valve removed, the cylinder is subject to contamination, condensation etc. (which is why it is sold with a valve and positive pressure in the first place). So when the cylinder arrives in US, I guess I would have the cylinder hydrotested and probably replace the DIN-477 Euro-Norm valve with a CGA-540 Standard North American (to facilitate refills).

On Tuesday, February 21, 2023 at 12:44:43 PM UTC-6, Dgtarmichael wrote:
> I wonder if that European tank will have a DOT stamp on it....
>
> Doug
> On Tuesday, February 21, 2023 at 9:59:40 AM UTC-6, son_of_flubber wrote:
> > New cylinders are usually sold with a valve and filled with slight positive pressure O2 to prevent contamination.
> > The EU retailer that I spoke with told me that hazardous materials shipping regulations required him to remove the valve prior to shipping. A visual inspection needs to be possible. I guess that this is maybe because O2 cylinders make great bombs and you can't look inside them with X-rays.
> >
> > With valve removed, the cylinder is subject to contamination, condensation etc. (which is why it is sold with a valve and positive pressure in the first place). So when the cylinder arrives in US, I guess I would have the cylinder hydrotested and probably replace the DIN-477 Euro-Norm valve with a CGA-540 Standard North American (to facilitate refills).

Thanks to Mark Mocho for his specific recommendations: AL180 or KF-011

Concerning length/size/fit: 3L_steel is 580mm, 2L_steel is 430mm, AL-180 is 300mm, and KF-011 is 485mm. LS8 POH recommends 3-4L_steel, so all of these options are smaller than the maximum recommended length.

Using MH EDS, endurance at 18k MSL for AL-180 is 3.8 hours, and for KF-011 is 7.2 hours.

MH price for AL-180 is $199, and for KF-011 is $745.

AL-180 is tiny 300mm/11.8in + valve + regulator. I'm curious whether it might be possible to mount two AL-180 (Experimental Racing/Exhibition air worthiness)? Or mount a larger cylinder somewhere other than the factory-provided sleeve. AL-180 is out of stock at MH.

I've rejected the option of importing cylinders from EU because of the immediate hassles, open questions about US certifications, and possible hassle with future O2 refill providers. Even if it is legal, the stamp on the cylinder might confuse some refill providers.

I may have a relatively unused AL-180 (but it may be out of date, meaning a hydrotest would be required). Not sure if I still have it, but I will check when I get back from the SSA Convention.

As another option, I have as a spare an oxygen bottle I used with an LS6 which I would think be the bottle size you need for your LS8. It would come with the MH bottle side regulator part as well, which was overhauled at MH recently.

Let me know if you want more info.... david.krautter@gmail.com

Agreed that importing a 100mm oxygen bottle can cause some confusion but if one was to decide to import one a couple of comments/questions come to mind.

> The bottles seem to be white (not green)
> The valve is a metric DIN477-9 (not a CGA-540)
> The valve handle seems to be blue (not silver or brass, chrome platted etc)
> Mountain high has regulators that fits the DIN477-9 valve. See https://www.mhoxygen.com/product-category/regulators/regulators-din-477-9/
> Could a metric tank be retrofitted with a CGA-540 valve? I imagine not.

- John (OHM)