When winter storms threaten to shut down commuter trains, New York City’s Metropolitan Transportation Authority blasts snow off the switches with jet engines. Built and mounted on railroad vehicles by mechanic Olie M. Ericksen, so-called snow jets use old aircraft engines as heating units. Ericksen replaced the original ignition systems with acetylene ones, which use a lower-voltage spark to ignite the fuel. “It actually works much better than the high-voltage spark, especially in colder temperatures,” he says. The jets can even blow or melt ice from the third rail (which provides trains with electric power) with 700- to 900-degree exhaust. Ericksen isn’t the first to build snow jets—the oldest one still in use dates back to the 1960s. And some onboard engines are even older: Certain snow trains still use J57s, the first American jet engine to produce more than 10,000 pounds of thrust.