For Sounding Balloons or Red Bull Stratos: Why not use hydrogen over helium

[quote author=Coding Badly link=topic=127916.msg962328#msg962328 date=1350609002]

Joule-Thomson appear to disagree with you...

I have first-hand knowledge that escaping hydrogen can ignite in the way I've described.[/quote]

And the lack of eyebrows to prove it XD