The Roadster can fly. Bring a stopwatch, not a pilot's license.

Good morning. Nine years after Tesla first showed us a Roadster, it showed us another one, and this one left the ground. It drove up a curved wall, hung there nearly upside down, hopped a row of parked Teslas, and landed on all four wheels with nobody inside. Today's two headliners share a small problem: neither is entirely welcome on a public road.

In today's newsletter, we'll get into:

Let’s roll.

Aston Martin's first motorcycle was never meant for the road, and this one hasn't been on any surface at all. The AMB 001 is a track-only bike built with Brough Superior in Toulouse, France, limited to 100 examples, and this is #032. Its owner bought it new from the factory in September 2023 and imported it in January 2024, and it shows zero miles. It's offered at no reserve in Doylestown, Pennsylvania, sat at $115,500 as of Sunday, and closes this afternoon at 1:10 PM ET.

The headline numbers are a turbocharged 997cc 88-degree V-twin rated at 180 horsepower in a bike that weighs about 180 kg dry, which works out to roughly one horsepower per kilogram. The turbo is variable-geometry, hardware you mostly find on diesel trucks and 911 Turbos, and the exhaust manifold is Inconel, the nickel alloy that shows up wherever exhaust heat is a problem. The engine is a stressed member. A CNC-machined aluminum backbone bolts straight to it, the carbon rear subframe hangs off titanium supports, and the swingarm pivots in the crankcases.

The front end is the part I'd spend the most time staring at. Instead of a telescopic fork, the AMB uses a Fior-type wishbone front, machined from billet aluminum and sprung by its own monoshock. Separating steering from suspension means the front barely dives under hard braking, so the geometry stays put from the brake marker to the apex. It's the same family of idea as BMW's Duolever, and it stays rare because it costs more to build and some riders find the feedback less familiar than a conventional fork. For a bike that will only ever see a track, it's a sound choice.

There are no gauges in the usual sense. Revs, speed, gear, engine map, and traction control appear on a Bluetooth-paired Samsung Galaxy phone that ships with the bike and mounts ahead of the tank, backed up by lamps for oil pressure, fuel, and neutral. So the instrument cluster on a six-figure Aston Martin depends on someone remembering to charge a 2023 phone. Under the lacquer on the tank's fin sit laser-cut stainless-steel wings nine microns thick, the same type used on the Valkyrie. The bike comes with certificates of authenticity and origin, the original invoice, import documents, a paddock stand, a coffee table book, the phone, and a battery charger.

The paperwork is a bill of sale, and it's sold for display or off-road use only. That doesn't matter on a track, but it means this bike can never be registered for the street.

The interesting context is another AMB 001. In May, #057, also unridden, was bid to $101,000 here and didn't sell, short of its roughly $119,000 original price. This one has no reserve, so it will sell, and it has already passed the point where that one stopped.

On Thursday night, at SpaceX's rocket test site in McGregor, Texas, Tesla revealed the production-intent Roadster. The event had been set for October 1 and was pushed two weeks for weather, which by Roadster standards counts as on time. Since the 2017 prototype, the car's production date has slipped at least six times and its reveal date at least seven.

The demo was the point. The car climbed a curved ramp to nearly upside down, held there by fans under the car that suck it toward the surface. It then let go, rolled upright on compressed-air thrusters, and landed. On a second run it jumped a lineup of Tesla products, Semi and Cybercab included, while spinning. Nobody was aboard. Reporters on site said the flying car was remotely controlled and bounced noticeably on landing. Tesla also ran a 0-to-60 mph launch with the rear thrusters firing and timed it at 0.81 seconds.

There are three versions:

Back in #27, we asked whether the car could hit its 2017 targets, and the scorecard is mixed. The 2017 car promised 0 to 60 in 1.9 seconds, and the new one claims under a second with thrusters. Top speed was promised above 250 mph and is now quoted as over 230 mph, with Musk saying he wants much more. Range was promised at 620 miles from a 200 kWh pack. Tesla gave no battery size on Thursday, and range figures reported from the event run from "not announced" to around 300 miles. The 2017 car's rear seats are gone, and on the Rocket the passenger seat gives way to an air tank.

Musk said production starts in 2028 and gave no price. He told the crowd he wasn't sure the car would move Tesla's revenue much, and said the thruster versions may not be legal everywhere. He also called it "the best of the last of the human-driven cars," which is an interesting way to market a car from a company that has spent the last two years selling the idea of not driving.

A post making the rounds on X put it bluntly. The car carries about 250 kg of compressed air plus the tanks and valves to hold it, that buys roughly 1.5 to 2 seconds of maximum thrust before a refill, and so the whole thing is a gimmick.

A cold-gas thruster is a pressurized tank, a valve, and a nozzle. There is no combustion. Gas expands through the nozzle, leaves faster than the speed of sound (the diamond pattern in the exhaust on the video is the giveaway), and pushes the car the other way. Thrust is mass flow times exhaust velocity, and compressed air is about the weakest propellant you can choose. Room-temperature air expanded through an ideal nozzle leaves at roughly 500 to 650 meters per second. A combustion rocket engine manages five to six times that. Cold gas wins on simplicity and safety, which is why spacecraft use it for small attitude corrections and not for getting anywhere.

Tesla said the car stores 600 liters of air in carbon-overwrapped pressure vessels, the same family of tank SpaceX flies. An in-car screen showed a thruster pressure readout of 5,500 psi, about 380 bar. Running real-gas property tables for air at that pressure and room temperature gives about 230 kg in 600 liters, so the post's 250 kg is close. That figure applies to the Rocket. The Thrust trim reportedly gets only 200 liters, about 75 kg of air.

Next I modeled the 600-liter tank emptying down to 20 bar through ideal nozzles, with two bookends. In a fast blowdown the gas cools as it expands, and the tank would drop to roughly minus 150 degrees Celsius by the end, which yields about 93 kN·s of total impulse. If the gas could somehow be held at room temperature, the figure rises to about 136 kN·s. Tesla says the thrusters make more than 80 kN. Divide one by the other and you get 1.2 to 1.7 seconds at full thrust, before any real-world nozzle losses. The post's 1.5 to 2 seconds is, if anything, generous.

Maximum thrust isn't what flying requires, though. Hovering only takes thrust equal to the car's weight. Tesla hasn't published one, and a reviewer at the event put it above 4,000 pounds, so call it 2,000 kg with the air aboard. That's about 20 kN, a quarter of the rated thrust, and the same tank buys roughly 5 to 7 seconds of hover in the ideal case. Each stunt on Thursday lasted a few seconds, so the stunts fit the tank. A trip to the grocery store does not.

The Thrust trim is the more interesting case for actual owners. Getting a 2,000 kg car from 0 to 60 mph in 0.81 seconds takes about 54 kN·s of impulse. Tires at a strong 1.2 g supply about 19 kN·s of that, which leaves the thrusters roughly 35 kN·s. The 200-liter tank holds somewhere between 31 and 45 kN·s. In other words, a Thrust owner gets about one sub-one-second launch per fill.

Refilling is the open question. Musk said the car can recharge its own tank and gave no time. Compressing 230 kg of air to 380 bar takes about 32 kWh even with a perfect compressor, and real multistage compressors need around twice that. Measured as free air, that's about 190,000 liters, and a typical high-pressure scuba compressor delivering 300 liters a minute would need roughly 10 hours for the Rocket's tanks and 3.5 hours for the Thrust's. Tesla hasn't said what's onboard, so that's a ceiling for comparison, not a spec.

There's still no price. What exists is a reservation: $50,000 for the Performance, paid as $5,000 up front and $45,000 within 10 days, and $250,000 for the Thrust, paid as $5,000 up front and $245,000 within 10 days. For reference, the 2017 car was listed at $200,000, and 1,000 Founders Series cars were offered at $250,000 paid in full. Adjusted for inflation, that $200,000 base price is roughly $270,000 in today's money. Thrust buyers are being asked to put down the entire 2017 Founders Series price as a deposit, for a car that may not be legal in their state.

Deposits are interest-free loans from customers. A $50,000 deposit placed in late 2017 and parked in Treasury bills instead would have earned somewhere around $13,000 to $14,000 by now, by my estimate. Anyone who has held a reservation since the original reveal has paid that for the privilege of waiting, and will keep paying through 2028. Tesla doesn't disclose reservation counts, but the math on its side is simple: every 1,000 Thrust reservations is $250 million in cash two years before production, worth about $10 million a year in interest at current rates.

Then there's scale. Tesla delivered 486,532 vehicles in the third quarter. If it eventually builds 5,000 Roadsters, that's about 1% of a single quarter's deliveries, spread over years. Musk said as much himself. The Roadster's job is attention. Tesla is now mostly a Model 3 and Model Y company making a large bet on autonomy, and a hand-built driver's car with SpaceX hardware keeps enthusiasts watching while that bet plays out. The thrusters and tanks come from a company Musk also runs, which is convenient for everyone involved.

Running costs are where it gets fun. The P Zero Trofeo RS tires will be the familiar expense. The air is the cheap part: at typical US residential electricity rates, a full refill of the Rocket's tanks works out to roughly $10 to $20, less than half a tank of gas, just with a much shorter trip on the other end. Insurance will be its own adventure. Somewhere, an agent is going to ask whether the vehicle has any modifications, and the honest answer will be ten rocket thrusters, factory installed.

That's a wrap. See you Wednesday — same inbox, lower gear.

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