Elon Musk joked his new car could detach your retina. Could it?
Tesla says its flying Roadster will only get quicker, up to the limit of the human body. We checked what eye science says about that limit.
Tesla has finally unveiled its second-generation Roadster, nine years after it was first promised. At a launch at SpaceX’s rocket test centre in McGregor, Texas, near Waco, on 15 October, the car hopped over a row of other vehicles on compressed-air thrusters and, in a live run, went from 0 to 96 km/h (60 mph) in 0.81 seconds.
Then Elon Musk said the production car would be even quicker. Citing Newton’s second law, he said more force and less mass would mean more acceleration. How much quicker? Tesla would, he said, “ride the limit of don’t detach the retina” of the person inside.
It was a joke. But it sets an unusual target: a car limited by the human body, not by its motor. So we looked at the science.
What 0.81 seconds does to you
Reaching 96 km/h in 0.81 seconds means an average push of about 3.4 g, more than three times your body weight pressing you back into the seat. Tesla says its top “Rocket” version will do it in under 0.59 seconds, a claim not yet shown in public. That works out to about 4.6 g on average, with brief peaks higher.
Which way the force pushes matters most
Pilots and astronauts have been tested for decades, and the main lesson is that direction matters. When g-force runs from head to toe, as in a fighter jet’s tight turn, blood drains away from the eyes. NASA research found untrained people start losing side vision at about 4.1 g and black out at about 4.7 g.
A car launch pushes you from chest to back instead, and the body copes far better. NASA research puts the seated limit for sustained chest-to-back g at about 8 g, and the limiting factors are breathing and chest pain, not eyesight. In very short pulses, people have taken around 40 g for a quarter of a second.
So can acceleration detach a retina?
The retina is the thin, light-sensing layer at the back of the eye. A detachment happens when it peels away from the tissue that supports it. It’s an emergency that can cause permanent vision loss.
Doctors have documented cases linked to acceleration, from roller coasters rather than cars. In 2024, eye specialists in Toronto reported two young women whose retinas detached after roller-coaster rides. Both already had risk factors: one had a family history of detachment, and the other was very short-sighted with weak areas of retina. Reviewing other reported cases, the authors concluded that a “structural predisposition is likely necessary.” In eyes without that weakness, similar forces caused bleeding, but not detachment. Two cases show a possible link, not proof, and they say nothing directly about a car.
Cases like these are rare. Answering a reader’s question for the American Academy of Ophthalmology, ophthalmologist Dr Richard Bensinger said roller coasters are “unlikely” to be a problem for short-sighted people.
The most extreme human test on record is US Air Force doctor John Paul Stapp’s. In 1954 he rode a rocket sled to 632 mph (about 1,017 km/h), then stopped in 1.4 seconds, taking 46.2 g. Almost all the tiny blood vessels in his eyes burst, and he feared his retinas had detached. He was temporarily blinded and left hospital the next day, but his eyesight was never quite the same. His was a sudden stop, not a launch, so it isn’t a safe or unsafe limit for a car; it shows how far human tests have gone.
Our verdict
No one has set a g-force at which a retina detaches. Force direction, how long it lasts and the state of the eye all matter. There is currently not enough evidence to show that the Roadster’s reported acceleration would cause retinal detachment in an otherwise healthy eye. For an eye that’s already vulnerable, the reported cases are rare, but they suggest a hard launch could matter, whether it comes from a roller coaster or a hypercar. So Musk’s joke points at a real risk, but the evidence doesn’t show it for most people at these speeds.
“The production car will actually do better than that.” Elon Musk, at the launch
Why it matters to you
- Know your risk. Retinal detachment is more likely if you’re very short-sighted, have a family history of it, have had eye surgery such as cataract removal or a serious eye injury, or are aged about 40 to 70.
- Before extreme rides such as launch roller coasters, theme-park thrill rides or track experiences, ask your eye doctor if any of those apply to you.
- Know the warning signs: a sudden shower of floaters, flashes of light, blurred vision, or a curtain-like shadow over your vision. These need care right away. It’s painless, so don’t wait. In Australia, see your GP or optometrist the same day, or go to an emergency department. In Sri Lanka, go to the nearest hospital eye unit.
- The car itself: Tesla is aiming to start production in 2028. It is taking reservations of US$50,000 to US$250,000, TechCrunch reported, and Musk said the car may not be legal in all places, so the thruster versions may never be road-legal in Australia or Sri Lanka.
How we worked it out: average g = 26.8 m/s (60 mph) ÷ time ÷ 9.81 m/s². These are average accelerations worked out from Tesla’s claimed times, not measured forces on the driver and not injury thresholds; peak forces will be higher. The human tolerance figures come from controlled tests and vary from person to person.
Sources: Tesla Roadster launch, 15 October 2026 (Tesla livestream); TechCrunch; Pickel et al., “Roller Coasters and Retinal Detachment”, Case Reports in Ophthalmology, 2024; American Academy of Ophthalmology; NASA Technical Reports Server, “Acceleration”; NASA, X-15; Smithsonian, SR-71; US Navy, F-16; US Air Force Safety Center; The Space Review; Airman magazine and Wright-Patterson Air Force Base; Mayo Clinic.
General information, not medical advice. If you have symptoms, get medical help straight away.