The Fan looks similar to what it name says. It is half as big as a box and is powered by Freckled pig or a engine. Its the first electrical item that appears in game.
Without a motor it's thrust is almost ridiculous except for the starting levels wich introduce the fan. Even if used with a V8, it's far weaker than a propeller. It's about the power of a propeller without a engine. If enough fans are attached to the bottom of the vehicle AND if it has enough engine power AND it is not too heavy, you can use it to hover.