I never understand the spark thing, I have thrown a lit match in gasoline and it just went out. Must be a spark and a small piece of metal from the starter or Alt that starts it. I never start the engines with the cover down so I would have seen the fuel, and smelled it for sure.

Fumes.

Gas FUMES will light with a small spark.

Liquid gas is much harder to light.

Liquid fuel won't burn...It's the atomized vapors that burn.

True, if it's windy a match will snuff out in liquid fuel. Don't try it, though.