Re: Helium Supply

Steve Aerospace
 

Ive been researching Operation Outward - a UK WW2 operation that launched 100,000 Hydrogen met balloons over a 2.5 year period (trailing wires and dropping incendiary devices on Germany).  There were many balloon ignition events and several of the operators were badly burned (no fatalities).  Some operators were burned (lost hair/eyebrows) from several meters away.  The balloons were filled outside in large canvas tents - and it would appear that the ignition came from rubbing against the fabric.

    Steve G8KHW

On 18/04/2018 07:37, Jayant Murthy via Groups.Io wrote:
We use only hydrogen because of the cost and because we can't always get helium. We have the tanks delivered a day before launch and store in an isolated place. We only fill the balloons outside where the hydrogen diffuses fast enough to not have safety issues and let teh remaining gas bleed out.

As long as you don't fill in an enclosed area there are no safety issues with hydrogen.
Jayant

On Wednesday, April 18, 2018, 12:03:25 PM GMT+5:30, Bill Brown via Groups.Io <wb8elk@...> wrote:


Actually using hydrogen is very safe. We launched 10 balloons at GPSL last year and the year before that and all were using hydrogen.  Walmart helium tanks are manufactured by BalloonTime. They have 8.9 or 14.9 cubic foot of helium inside depending on whether you use the standard or jumbo size tanks (about $25 to $40 each tank). Enough for 3 pico balloons (36-inch Mylar foil balloons) but it would take a lot of those canisters to fly a large latex balloon which would be more expensive than a large tank even with the crazy price gouging they do to private individuals at the big gas supply houses. The other drawback to BalloonTime canisters is that about a year or so ago they started to do a "Specially Formulated blend that won't affect performance". The marketing folks had to work overtime on that one. Turns out that they are now selling 80 percent pure helium instead of the 98 percent pure helium they used to sell....and of course at a higher price. I had a long chat with a manager at their factory in Columbus, Ohio who claimed it wouldn't affect performance at all. Nice to see that marketing folks can change the gas laws :-( They won't consider doing a special run of pure helium either.

So go with a $55 large tank of hydrogen. You'll get better lift performance as a bonus. You will need a CGA-580 to CGA-350 adaptor to use a helium regulator with a hydrogen tank but the adapter can be bought on Amazon for around $15. Also, don't crack open a hydrogen tank unless there is a regulator on it.

I sometimes use the BalloonTime canisters for a Pico balloon flight in a school event since it is very convenient to not have to lug around a large tank.

- Bill WB8ELK










-----Original Message-----
From: jasonbunwin via Groups.Io <jasonbunwin@...>
To: gpsl <gpsl@groups.io>
Sent: Wed, Apr 18, 2018 1:08 am
Subject: Re: [GPSL] Helium Supply

I am trying to organize an HAB flight for Civil Air Patrol. Praxair told us they won't sell helium to new customers. There are a lot of safety concerns about hydrogen. Is it possible to make a "blend" of hydrogen and helium that will make it less "dangerous" and lower cost? One group in Illinois is using Walmart helium tanks for their flight. That worked out be crazy expensive per cubic foot.

Jason Unwin
KF5UEF


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