- Yes, the just-revealed Tesla Roadster astonished the reveal crowd by jumping without a ramp and driving upside down, but how did it do that?
- The electric sports car was able to lift off using cold-gas thruster technology from SpaceX and 250 kilos of compressed air.
- We’re not saying any of this will make it to production, but at least we can explain what we saw.
Elon Musk has launched a Tesla Roadster all the way to space, but it was the much lower-altitude stunt reveal of the new Tesla Roadster that showed how much spectacle can still find an audience. While the two highlights—a jump-slash-flip and driving upside down on a half-circle ramp—felt like scenes from an action movie, they were real. Just like the movies, though, a bit of behind-the-scenes magic was needed to make it happen, like out-of-this-world components from SpaceX. Here’s how the new Tesla Roadster defied gravity in Texas.
Thrust from SpaceX
Let’s start with the basics. The new Roadster is said to weigh around 3700 pounds and is rear-wheel drive only, with two electric motors in the rear that are said to produce up to 1500 horsepower and more torque than any Tesla Model S Plaid. The coupe with butterfly doors uses a steer-by-wire yoke, brake, and throttle to accomplish some of its tricks. It also features a Roadster-specific 4680 Tesla battery cell that’s claimed to be the fastest-charging version the company has ever produced. And if you’re wondering about range, it’s claimed to be over 300 miles.
The fantasy Rocket trim was the star of the reveal, doing a “kickflip” jump over five other Tesla vehicles, including a Semi, rising up over them without a ramp and landing well clear on the other side. The Rocket Roadster that performed the stunt used two carbon overlay pressure vessels with a 600-liter capacity that held a total of 250 kilos of air. These tanks eliminate the passenger seat.
Liftoff was accomplished by running highly pressurized air through a system of 10 nozzles that mimic a rocket’s thrusters. Tesla said these cold-gas thrusters are positioned around the perimeter of the vehicle to support forward and upward acceleration as well as lateral rotational movement using all-electric actuators that offer precise micro-adjustments.
Tesla CEO Elon Musk said during the event that the Rocket Roadster uses an “advanced ultra-high pressure air tank” that doesn’t need any special propellant. “Literally, it’s just going to puff itself up, and you’ll be able to do these maneuvers whenever you'd like,” he said, but we’ve learned not to trust Musk’s statements until whatever product he’s talking about comes to market. The Tesla website says the Rocket model will be available by invite only and is “not approved for public road use.”
Sucks to Stick
Of more real-world interest to drivers is the downforce generated by the new multi-mode fan and ground-sealing system, which provides enough suction that the vehicle can technically sit on an upside-down road, even at a standstill. The fans pull air out from beneath the vehicle and, when used on right-side-up roads, the fans and active wings help maximize traction and cornering speeds in all conditions by delivering up to 2 g’s of downforce when going 200 mph, but not as much at lower speeds.
During the Roadster’s reveal, Lars Moravy, VP for vehicle engineering at Tesla, said the fan system was designed to have two modes. It can suck the car down at low speed to give the vehicle extra traction when needed and, at high speeds, the front and rear parts of the suction system open up to create even more flow underneath the car.
“In sucker mode, we can actually pull the car down,” Moravy told Hagerty. “That means that void of aero space, from zero to 50 [mph], when these wings aren’t doing anything, we can hold over 2 g’s in a corner. When we’re accelerating, we can break the laws of tire physics.”
The four fans in the rear are higher-capacity versions of the high-voltage compressor motor that runs the heat pump in the new Roadster’s thermal system. The base heat pump motor is 12 kW, while the rear fans are 20 kW. The rear wing has a variable pitch that will dynamically adjust itself to generate the downforce required on the track. The limited Thrust trim with this suction system is claimed to be able to go from zero to 60 mph in under one second.
