LOL,,, they had some upright pipes venting propane gas to fuel the flame on both sides of the track that the riders jumped past.
Ken I think the word you are looking for is Methane Gas. What you have here looks like to me is rider jumping past a "Methane flare" (Methane tower flare), common in (closed) landfills to burn off excess Methane gas from the ground trapped underneath.
Looks like your hill climb was at an old landfill of some kind. If it is Methane gas it would be the same gas "Pinto Beans" would produce, but on a much larger scale.
One big
Pyroflatulence is the correct name. A "Blue flame fart" or "Blue Angel" are two of the urban nicknames used for this practice. (Don't try this at home.........Pete! lol)
Flatulence produces a mixture of gases with the following six as major components:
Carbon dioxide, Hydrogen, Hydrogen sulfide,
Methane, Nitrogen, and Oxygen. Igniting the gases produced by human flatulence, often producing a flame of a blue hue much to the same as a "Methane flare"
So that's today's science lesson boys and girls. Guess I really know my $hit. I should, because for the last 20 years I have been an Illinois Certified Pyrotechnic Operator for Display Fireworks. I shot Forth of July fireworks shows and other displays for different events. If it goes boom or burns, I got the knowledge to make it do it.
BTW Great shot Ken
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