1 foot per second??? Whoever made that statement never threw a cup of gasoline on a fire... I promise you it travels much faster than that.

https://www.youtube.com/watch?v=Hi7tZVV-o8A

Notice the flame first enters the field of view at the 45 second mark and by the 47 second mark has covered at least 20 feet and looks like more than that honestly and this is not exactly an ideal AF mix.

I am not causing global warming, I am just trying to hold off a impending Ice Age!