Posted on 09/29/2026 4:08:45 PM PDT by ProtectOurFreedom
Tesla was just granted a patent for an “Electric Fan Car,” a system that uses four electric ducted fans in the rear diffuser to suck the car down to the road at any speed. The car in the drawings is a Model S, which Tesla stopped building in April. It’s Tesla’s second fan car patent in just over a year, and it arrives two weeks before the company’s latest attempt at a Roadster demo.
The USPTO granted US 12,746,987 B1 today. Tesla filed it in January 2024, but it goes back to a provisional application from January 17, 2023. Eight inventors are listed, and all but one are based in the Los Angeles area, where Tesla has its design studio in Hawthorne.
The idea is simple. An inlet on the underbody, between the rear wheels, feeds a duct that sweeps up to a wide outlet in the rear diffuser. Four axial fans sit side by side in that outlet, split by three vertical strakes. When they spin up, they evacuate the air under the floor and exhaust it through the rear.
Tesla Electric Fan Car patent FIG. 1 side view of a Model S showing the airflow path through the rear ducted fan system. FIG. 1 from Tesla’s patent: air flows under the Model S, into the inlet (13), and out through the fans (10) at the rear. Credit: USPTO
That creates what Tesla calls a “suction region” under the floor. A vacuum. The rear end also gets a raked plate that acts as a second diffuser.
Tesla Electric Fan Car patent FIG. 2 rear view of a Model S with four electric ducted fans in the rear diffuser. FIG. 2: four electric ducted fans (10) separated by strakes (15) in the Model S rear diffuser. Credit: USPTO
Tesla’s pitch is about speed independence. The filing notes that passive diffusers limit downforce at low speed and “often results in an excessive load at a high speed.” The fans, according to Tesla, “can produce a downforce independent of the vehicle velocity,” which helps with braking stability and cornering speed.
There’s one clever detail. A second version adds two smaller side inlets behind the main one, because Tesla says the central inlet tends to pull air forward from behind the car instead of from under the floor. That backwash adds no downforce, and Tesla says the fans end up “wasting power” on it.
Power comes from the same high-voltage pack that drives the wheels, so there’s no separate motor or battery for the fans, and they’re tied into the car’s control system. The driver can switch them on with a button, or the car can do it automatically at certain speeds.
Drawn on a car Tesla doesn’t make anymore
You can’t miss the Model S in these drawings. The fastback roofline, taillights, lip spoiler and door handles are all there. In early 2023, when Tesla filed the provisional, that made sense. The Model S Plaid was Tesla’s performance flagship, and a fan-assisted track version would have been a fun halo. But Tesla ended Model S and Model X production in April after 14 years, and it’s turning the Fremont line over to Optimus. So that’s not happening.
Which leaves the Roadster, the only performance car Tesla still has in the pipeline. Last week, we reported on a Tesla patent for a hidden active rear wing good for up to 700 kg of downforce, drawn on a car that looks just like the new Roadster. And in August 2025, Tesla got another fan car patent using underbody fans and deployable skirts. Fans plus an active wing is a full track aero package, and the Roadster is the only car left to put it on.
Fan cars are nothing new
None of this is new. Chaparral raced the 2J in 1970 with two fans driven by a separate snowmobile engine. Brabham’s BT46B won the 1978 Swedish Grand Prix with Niki Lauda and was withdrawn right after. Gordon Murray put a 400 mm fan on the back of the T.50 road car.
And on the electric side, McMurtry has been doing it for years. Its Spéirling smashed the all-time Goodwood hill climb record in June 2022, about seven months before Tesla filed its provisional. It makes 2,000 kg of downforce at a standstill, has driven upside down, and McMurtry started production of the $1.36 million Spéirling PURE earlier this year. Its fans also run off the main battery.
Tesla’s main twist is that its design doesn’t need skirts sealing the car to the ground. The filing says the fans can work “without use of additional elements below the vehicle,” and packages them into a normal-looking diffuser.
...more at site...
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Those roads better be squeaky clean.
Proving electric cars do blow.
I think that it will be able to blow as well as Suck.
iirc Musk mentioned something about limited flying ability.
many years ago my kids told me about one of their friends fathers who was mexican and had modified his car so it had state of the art hydraulics, and how it could jump over speed bumps and they thought it was the coolest thing ever (I never saw it)
But I remember when Bose tried to do do the same thing with active dampers on an ls400 if I remember right, and then I designed a few as an exercise, at the time not really so practical, but today there is a lot of stuff which is much more possible.
Someone having fun make a Telsa into an either a Brabham F1 fan car or a Chaparral 2J CanAm car. Don’t hold you breath for this one............
there’s no separate motor or battery for the fans
++++++++++++++++++++++++++++++
no separate motor? for the fans? Alrighty...
My Tesla S is full of eels.
(The concept sounds like a hovercraft in reverse.)
The electric vehicles are a lot heavier than comparable gas ones.
Why do they need additional down force?
Better not hit a big pile of cow 💩 with that thing. I’d hate to be in the car behind it😬
BRILLIANT - Who needs a drive train when you have a fan train...or something like that?
Here is a link to Searchable Text at USPTO. Strangely, the word "motor" does not appear even once in the text!
The word "fan" appears 85 times! "Electric" appears 91 times.
I don't know how the author jumped to that conclusion based on the patent. The patent discusses the airflow path and downforce created by the airflow, but only obliquely mentions the motive force for the fans.
"Further, an electric fan car according to this disclosure can include a ducted fan system 1 integrated into the electric vehicle 100 with minimal visual intrusion and limitation on the vehicle's functionality. For example, the ducted fan system 1 may not require additional gearing from an engine or an additional power source dedicated to the EDFs. In some embodiments, the EDFs are connected directly to the high voltage (HV) battery 30 of the electric vehicle 100 for receiving power 31 and to enable a compact and integrated system execution. For example, in some embodiments, the electric ducted fans 10 may be connected directly to the HV battery 30 of the electric vehicle 100 as shown in FIG. 4."The fans connected directly to the HV battery obviously means motor-driven fans. And the "joinders"...
All joinder references (e.g., attached, affixed, coupled, connected, and the like) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.
To drive on the ceiling like the Porsche 956! Duh!
(We saw this exhibit a couple weeks ago in at the Porsche Museum in Stuttgart!)
LOL SPLAT!!
I’d be afraid to drive to close to it and get sucked sideways, attracted like a giant magnet.
‘”Why do they need additional down force?”
To drive on the ceiling like the Porsche 956! Duh!’
___________________________________________________________
Wow, Porsches really DO have some traction!
But he was being facetious -- if not out-and-out lying -- because the Brabham used radial fans. So I suspect the Tesla design does as well. Because radial fans can't throw anything out the back.
Sometimes car companies patent things just because they thought of something clever and they want to make sure that if anyone else wants to use it, they can make money off it. Or they sometimes patent things just to prevent anybody else using it.
Last year Ferrari patented an engine using ovalized pistons that were lengthened perpendicular to the crankshaft. This would let them crowd the bore centers closer together so they could build a V-12 that was as short as a V-8.
They couldn't have used it in their F1 cars because F1 already has banned ovalized pistons on account of the Honda NR500 motorcycle with ovalized pistons (lengthened in line with the crankshaft). And if they intend building a road car with it, there's no hint of it yet.
Top, Ferrari. Bottom, Honda.
Big problem... Roads aren’t clean. They’re typically full of rubber debris from tires, rocks, dirt, etc., etc.
These fans are going to clog up with all that debris.
Big 3 would patent nonsense stuff just to stop anyone else from doing it first.
Im imaging the typical game of chickenit seems every squirrel and chipmunk like to play. Somehow Im astride the little beast just as it gets sucked up. The driver behind me gets a sudden rodent anatomy lesson splayed across his windshield.
How much will this reduce the range?
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