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How SpaceX is able to achieve its amazing rocket landing accuracy

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8 years ago

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After SpaceX’s successful and uniquely exciting launch of Taiwan’s Formosat-5 remote sensing satellite, Elon Musk took to Twitter to reveal some fascinating details about the launch and recovery of the Falcon 9 first stage.

Unabashedly technical, the details Musk revealed demonstrate the truly incredible accuracy of Falcon 9’s recovery, honed over 20 landing attempts and numerous modifications to the launch vehicle. The accuracy is best understood within the context of Falcon 9’s scale and the general scope of orbital rocketry.

The first stage of Falcon 9 Full Thrust, currently the active version of Falcon 9, stands 140 feet tall and 12 feet in diameter. If you can, for a moment, picture a 737 airliner, the plane most people have likely flown aboard on domestic flights. The first stage of Falcon 9 is the same length or greater and the same diameter as Boeing’s workhorse airliner. If you are now imagining a 737 landing on its tail aboard an ocean-going barge, that is a great start. The most common version of the 737, the -800, has an empty weight of 91,000 lb, while Falcon 9’s empty first stage is a bit more than half as heavy. With a full load of fuel, Falcon 9 S1 (first stage) weighs nearly three times as much as the 737-800. A single Merlin 1D engine out of Falcon 9’s namesake nine rocket engines has nearly ten times the thrust of the airliner. In short, Falcon 9’s first stage is massive, both extremely light and extremely heavy, and has a mind-boggling amount of thrust.

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Falcon 9’s ability to land as accurately as it does is due to a combination of multiple technologies and vehicle modifications. Most visible are S1’s cold gas maneuvering thrusters and aluminum or titanium grid fins, both of which are designed to provide some level of control authority and maneuverability to the first stage during its trip within and without Earth’s atmosphere. At the peak of its trips, the first stage is often completely outside of the vast majority of the atmosphere, meaning that aerodynamic forces are no longer relevant or useful for the vehicle. This is where the cold gas thrusters come in: by carrying their reaction mass with them (the gas), Falcon 9 can maneuver outside of the atmosphere. Once the stage descends into thicker atmospheric conditions, the grid fins deploy and are used like wings to guide the stage down to its landing location, be that on land or at sea. While the gas thrusters lose a lot of their utility once in the atmosphere, they can still be used to add a small amount of control authority when needed. They were famously seen fighting a futile battle to save a first stage aboard OCISLY in 2015.

With this in mind, we can take a closer look at Musk’s technical details. First off, we have a photo of the landed booster, Falcon 9 1038, clearly almost dead center on the droneship Just Read The Instructions. More specifically, Musk reports that 1038 landed less than a single meter off the center of the target, and it landed with less than a single meter per second of latent velocity. The first stage thus managed both a soft and deadly accurate landing after traveling to a height of 150 miles – well into what is technically “space” – at a maximum speed of 1.5 miles per second. Without delving further into the details, this is best summarized as “insanely fast”, and is a bit faster than the X-15 rocketplane’s fastest recorded speed. To better put this into context, Falcon 9 1038 traveled to an altitude of 240,000 meters at a top speed of 2,400 meters per second, turned around, and landed on an autonomous barge about two feet off of its optimal target. It is truly difficult to describe how impressive that kind of accuracy is.

The hypersonic X-15 and Falcon 9 S1, with a 737-800 on the right. All vehicles are to scale. (Wikipedia, SpaceX)

Mr. Musk nevertheless did not let 1038 steal all the fanfare, and revealed that the first stage responsible for launching BulgariaSat-1, 1029, had the honor of being the fastest first stage yet, clocking in at at a truly staggering Mach 7.9, or 2,700 meters per second. That speedy mission marked the stage’s second flight and was SpaceX’s second successful reuse of a Falcon 9. Indicative of the intense speed and heat the core experienced, one of the vehicle’s grid fins was noted to have almost completely melted through. Aluminum’s melting point begins at 1,221°F.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Tesla adjusts Robotaxi safety monitor strategy in Austin with new service area

The positioning of the driver, as well as the driver’s hands being closer to the steering wheel, is more similar to what Tesla is doing in the Bay Area Robotaxi program than it is to what it has done in Austin.

Published

15 hours ago

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September 2, 2025

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Credit: @AdanGuajardo/X

Tesla has adjusted its Robotaxi safety monitor strategy in Austin after it expanded its service area in the city last week for the third time.

Tesla has been operating its Robotaxi platform in Austin since June 22. The vehicles have been operated without a driver, but Tesla has placed safety monitors in the passenger’s seat as a precaution.

The safety monitors are responsible for performing any necessary interventions and maintaining a safe and comfortable cabin for riders as they experience Tesla’s first venture into the driverless ride-sharing space.

Last week, Tesla expanded its service area in Austin for the third time, expanding it from about 90 square miles to 170 square miles. The expansion included new territory, including the Austin-Bergstrom International Airport, Tesla’s Gigafactory Texas, and several freeways.

Tesla Robotaxi geofence expansion enters Plaid Mode and includes a surprise

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The freeway is an area that is uncharted territory for the Tesla Robotaxi program, and this fact alone encouraged Tesla to switch up its safety monitor positioning for the time being.

For now, they will be riding in the driver’s seat when routes require freeway travel:

The positioning of the driver, as well as the driver’s hands being closer to the steering wheel, is more similar to what Tesla is doing in the Bay Area Robotaxi program than it is to what it has done in Austin.

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This is sure to draw criticism from skeptics, but it is simply a step to keep things controlled and safe while the first Robotaxi drives take passengers on the highway with this version of the Full Self-Driving software.

This FSD version differs from the one that customers have in their own vehicles, but CEO Elon Musk has indicated something big is coming soon. FSD v14 is coming to vehicles in the near future, and Musk has said its performance is pretty incredible.

Tesla’s Elon Musk shares optimistic teaser about FSD V14: “Feels sentient”

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Tesla has best month ever in Turkey with drastic spike in sales

Tesla managed to sell 8,730 Model Y vehicles in Turkey, outpacing almost every competitor by a substantial margin. Only one brand sold better than Tesla in August in Turkey, and it was Renault.

Published

16 hours ago

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September 2, 2025

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Credit: Tesla

Tesla had its best monthly performance ever in Turkey in August, thanks to a drastic spike in sales.

Tesla saw an 86 percent bump in sales of the new Model Y in Turkey in August compared to July, dominating the market.

The performance was one of Tesla’s best in the market, and the company’s sales for the month accounted for half of all EV sales in Turkey for August, as it dominated and led BYD, which was the second-best-selling brand with just 1,639 units sold.

Tesla managed to sell 8,730 Model Y vehicles in Turkey, outpacing almost every competitor by a substantial margin. Only one brand sold better than Tesla in August in Turkey, and it was Renault.

Electric vehicles are, in some ways, more desirable than their gas counterparts in Turkey for several reasons. Most of the reasoning is financial.

First, EVs are subject to a lower Special Consumption Tax in Turkey. EVs can range from 25 percent to up to 170 percent, but this is less than the 70 to 220 percent rate that gas-powered vehicles can face. The tax is dependent on engine size.

Elon Musk courted to build a Tesla factory in Turkey

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Additionally, EVs are exempt from the annual Motor Vehicle Tax for the first ten years, providing consumers with a long-term ownership advantage. There are also credits that can amount to $30,000 in breaks, which makes them more accessible and brings down the cost of ownership.

Let’s not forget the other advantages that are felt regardless of country: cheaper fuel costs, reduced maintenance, and improved performance.

The base Model Y is the only configuration available in Turkey currently.

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Tesla is upgrading airbag safety through a crazy software update

“This upgrade builds upon your vehicle’s superior crash protection by now using Tesla Vision to help offer some of the most cutting-edge airbag performance in the event of a frontal crash.”

Published

18 hours ago

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September 2, 2025

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(Credit: Tesla)

Tesla is upgrading airbag safety through a crazy software update, which will utilize the company’s vision-first approach to enable better protection in the event of an accident.

Over the years, Tesla has gained an incredible reputation for prioritizing safety in its vehicles, with crash test ratings at the forefront of its engineers’ minds.

This has led to Tesla gaining numerous five-star safety ratings and awards related to safety. It is not just a statistical thing, either. In the real world, we’ve seen Teslas demonstrate some impressive examples of crash safety.

Everything from that glass roof not caving in when a tree falls on it to a Model Y surviving a drive off a cliff has been recorded.

However, Tesla is always looking to improve safety, and unlike most companies, it does not need a physical hardware update to do so. It can enhance features such as crash response and airbag performance through Over-the-Air software updates, which download automatically to the vehicle.

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In Tesla’s 2025.32 Software Update, the company is rolling out a Frontal Airbag System Enhancement, which aims to use Tesla Vision, the company’s camera-based approach to self-driving, to keep occupants safe.

The release notes state (via NotaTeslaApp):

“This upgrade builds upon your vehicle’s superior crash protection by now using Tesla Vision to help offer some of the most cutting-edge airbag performance in the event of a frontal crash. Building on top of regulatory and industry crash testing, this release enables front airbags to begin to inflate and restrain occupants earlier, in a way that only Tesla’s integrated systems are capable of doing, making your car safer over time.”

The use of cameras to predict a better time to restrain occupants with seatbelts and inflate airbags prior to a collision is a fantastic way to prevent injuries and limit harm done to those in the vehicle.

The feature is currently limited to the Model Y.

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