[farming pharmer]

I was thinking we should develop aircraft to spray cold cryogenic liquid on a fire. Smother the fire and freeze the area. But chances are this isn’t possible or practical to make a plane flying hundreds of miles per hour to spray liquid nitrogen, liquid helium, or the other cold non oxygen gases in a cold liquid state.

That's an idea. How bout solid dry ice? Cheap, plentiful and hugs the ground.

[Morpheus2009]

Yeah, that’s even better.