Tesla's Roadster took off, and the numbers stayed on the ground

The car came off an inverted ramp, turned over in the air and landed on its wheels. It also lifted itself over a queue of Tesla's own vehicles, a Semi lorry among them, using nothing but compressed gas. Almost nine years after the second-generation Roadster concept was first shown, Tesla revealed the car it now intends to build at an event outside SpaceX's rocket development site in McGregor, Texas, on the evening of 15 October. In Britain that was the early hours of Friday.

What it actually is

Start with the thing Tesla did not put on a banner. This is not a production car. Franz von Holzhausen, Tesla's chief designer, called it "a prototype with production intent", which puts it well beyond a show-stand concept and short of a finished specification. Elon Musk said on stage that Tesla is targeting the start of production in 2028. The 2017 concept was supposed to reach production in 2020, and the date moved to 2021, then 2022, 2023 and 2024 before the company stopped giving dates.

Three versions, one of which flies

Tesla has split the car three ways. Performance is the road version: two motors at the rear, four electric fans under the back bumper that pull air out from beneath the car to hold it down, and an active rear wing that tilts through 90 degrees to shed speed. Tesla quotes 0-60mph in under 1.6 seconds and a top speed above 210mph.

Thrust adds a tank of compressed nitrogen behind the seats and four cold-gas thrusters, which is where the sub-one-second acceleration claim comes from, and a top speed target of about 383mph. Rocket removes the passenger seat, doubles the gas capacity to 600 litres and fits ten thrusters around the car. Rocket is the one that flew, and it is invite only.

The claims problem

Every performance figure above is a Tesla claim. None of it has been independently tested, and the demonstration was staged by the company, on the company's ground, in front of an audience it had invited. The under-one-second figure belongs to Thrust and Rocket, the versions with thrusters, not to the car that most buyers would think of as the Roadster. The 383mph number is a target rather than a result. Tesla has not published a price for any version, and the battery capacity has not been finalised.

That matters more than usual here, because the demonstration was so good. A car that drives up a wall and rolls in mid-air is doing something real, and the footage is not a rendering. It is also not evidence of what a customer car will do on a British road in British weather.

The numbers that were published

What Tesla did put figures against is more modest than the headlines. The drive unit is claimed to produce 1 megawatt, about 500kW at each motor. Tesla puts that at roughly 1,500 horsepower and about 1,000 lb-ft of torque. Target kerb weight is 1,700kg. Estimated range is more than 300 miles, and charging from 10% to 80% should take 10 to 12 minutes. Those are the figures a buyer on this side of the Atlantic would actually live with, and they arrive with the same caveat as everything else on the night.

The hardware underneath is more interesting than the theatre. The pack uses Tesla's 4680 cylindrical cells with a titanium cover. The two motors are derived from the Model S Plaid's unit, and Tesla says the Roadster's drive unit is 30% lighter and 50% more powerful than the Plaid's. Braking, steering and throttle are all by wire, the dampers are spool-valve units with 40mm of ride height adjustment, and the roof is a T-top. Some of that will survive into production. Some of it will not.

Against the 2017 promise

The comparison that Tesla would rather you did not make is with its own launch material from nine years ago. Autocar recorded the original claims as 0-60mph in 1.9 seconds, a top speed of more than 250mph and a 620-mile range. The car shown this week is quoted at more than 300 miles and a little over 210mph in its road trim.

Range figures from 2017 and 2026 are not directly comparable, since the test cycles and the claims behind them have both changed, and Tesla has not published a number that would let you line them up properly. It is still worth noticing that nine years of battery development have produced a car with a shorter quoted range than the concept it replaces. That is what happens when a concept is built to a press release and a production car is built to a cost.

Why it matters in Britain, eventually

There is no UK price, no UK on-sale date and no confirmation that the car will be built in right-hand drive. Tesla is taking reservations, with the Rocket version invite only, and has not named a price for any of the three. Even on Tesla's own timeline, production begins in 2028, which is well after the next wave of electric cars reaches British showrooms.

The Roadster's real function is not sales. Musk has positioned it as a halo car, saying he is not sure it moves the needle massively from a revenue standpoint, and the reaction it generated this week is worth more to Tesla than the margin on a few thousand cars. That is a legitimate thing for a car company to do. Jaguar's Type 01 is making the same argument this month with a flagship of its own, and both brands are using one car to say they still build things people want.

None of this makes the Roadster a con. Tesla built a car that drives upside down and jumps over a lorry, and it did it where people could watch. The point is what a British buyer can do with it, which is nothing yet. When there is a price, a right-hand-drive confirmation and a car that has been timed by somebody other than the company that made it, the Roadster becomes a story about a car. Until then it is a story about a demonstration, and a very good one.