For most of adults, the sight of a big brown UPS truck, with its all-brown-clad driver, pulling into the driveway of your home is about as exciting as it would be for a kid to see an ice cream truck rolling down his or her street. “What can brown do for you?” Well, most of the time it’s bringing something you ordered online & have been impatiently tracking online ever since you placed your order. As exciting as UPS trucks may be, though, they also have their quirks. If you were to look closely, you’d notice most UPS trucks have some unusual spinning contraption perched atop their roofs. What is that?

That is actually a Flettner ventilator, and it’s purpose is pretty simple: to keep air circulating within the vehicle on which it’s been installed. UPS trucks can’t really run air conditioning due to the fact that the doors are almost always open so drivers can enter & exit expeditiously. So, in place of A/C, Flettner ventilators are put in place to keep air circulating so that neither the vehicle cabin or package area overheat. Because Flettner ventilators are wind-powered, whenever the vehicle is in motion (or if it’s an especially windy day out), the unit spins & generates air movement within the vehicle. According to Flettner, the ventilator can effectively lower each truck’s interior temperature anywhere from ten to a full fifteen degrees! And UPS trucks aren’t the only vehicles you’ll find Flettner ventilators, either; if you were to look closely, you’d likely also see them on other cargo trucks & Amazon delivery vans.

If you’d like to get your hands on a Flettner ventilator that’s already been installed on a UPS truck…well, sorry but that ain’t gonna happen. UPS actually forbids the resale of any of their fleet vehicles. Where do they go & what happens to them then? Well, older models are either reassigned to lighter internal company service duty, or they ultimately get scrapped. But if you’d like your very own Flettner ventilator, sans the UPS truck, you’re in luck! They’re actually available online through a variety of distributors.

If you’d like an answer to your very own Mundane Mystery, however, just send me a message via Twitter (@AndyWebbRadio), or shoot me an email at [email protected]!

BROUGHT TO YOU BY: Berryville Graphics