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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 Full Self-Driving (Supervised) v14.1.7 real-world drive and review

On an hour-long drive, we tested v14.1.7 and tested its new capabilities, which are mostly overall performance and smoothness fixes rather than integrations of new features that are unknown to routine FSD users.

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4 hours ago

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November 13, 2025

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tesla interior operating on full self driving
Credit: TESLARATI

Tesla started rolling out its Full Self-Driving (Supervised) v14.1.7 suite last night to owners, and there are several improvements to note within the new update that are at least the start of fixes to highly-mentioned issues.

On an hour-long drive, we tested v14.1.7 and tested its new capabilities, which are mostly overall performance and smoothness fixes rather than integrations of new features that are unknown to routine FSD users. However, there are a handful of shortcomings that are still present within the suite, which are not something that will be fixed within the span of a single update.

For what it is, Full Self-Driving does an excellent job of navigating — once you get it on its correct path. Our issues tend to be confined to navigation, routing, and the decision-making process that has to do with the way the car wants to get you to your destination. There were five things that happened on our first drive with v14.1.7 that are worth mentioning. The full drive will be available at the bottom of this article.

Navigation and Routing Still Seems to Be a Major Challenge

In past content, we’ve discussed the issues with routing and navigation, and how a Tesla chooses its path. Most noticeably, these issues occur in the same areas; for me, it’s my local Supercharger. My 2026 Model Y with AI4 continues to pick less-than-optimal routes out of the Supercharger, and in this instance, it actually chose to turn down a road, pull over, and give me the wheel, essentially asking, “Hey, can you get me on the right track here?”

This is still my biggest bone to pick with FSD, even more so than some of the bonehead moves it’s made in tougher scenarios (mostly parking lots with very limited visibility due to shrubs being planted in the worst possible locations). It’s rare that it happens, but this particular Supercharger has been a true thorn in the side of my Tesla.

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This is not an issue that is confined to v14.1.7, or even v14 in general. Unfortunately, it is an issue that has persisted throughout my ownership experience, as well as during Demo Drives.

Stuttering and Hesitation at Intersections was Non-Existent

There was some confusion regarding my language in a recent article where I stated Tesla is confronting the issues that have been reported regarding the “stabbing” with braking.

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“Tesla began the v14.1.4 launch last night, which included minor improvements and addressed brake-stabbing issues many owners have reported. In my personal experience, the stabbing has been awful on v14.1.3, and is a major concern.

However, many things have improved, and only a couple of minor issues have been recurring. Many of the issues v13 addressed are no longer an issue, so Tesla has made significant progress.”

It has undoubtedly improved, but it is not resolved.

With that being said, I did not feel a single example of hesitation, stabbing, or stuttering at a single intersection or instance when it has been present in the past. CEO Elon Musk said it would be fixed with v14.2, so it seems like Tesla is well on its way to resolving it.

Proper Handling of Crosswalks

It’s crazy how many people still do not stop for pedestrians at clearly-marked crosswalks. I had two instances of it happen during the drive, with FSD stopping for those pedestrians both times.

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Human drivers did not stop either time:

Handled Merging onto a Highway with an Inconsiderate Driver Well

Routinely, drivers will get over into the left lane, if they are able, to allow merging traffic to safely enter the freeway. It does not always happen this way, and it’s not required by law.

Not exclusive to v14.1.7, as many past iterations would have done this as well, but it was nice to watch the vehicle slow down to let that traffic pass. It then entered the freeway safely, and the entire maneuver was well done.

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Took an Appropriate Move with Oncoming Foot Traffic and Debris in a Tight Alleyway

This was probably the most on-edge I was during the drive because: 1) FSD chose to take an unnecessary alleyway, and 2) there was a box and oncoming pedestrians.

The car was aware of everything that was going on. In order to avoid the box, it would have had to turn toward the pedestrians, and in order to avoid the pedestrians, it would have had to turn into the box.

It chose to wait patiently, and after the pedestrians were past the car, FSD chose to proceed.

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Closing Thoughts

Overall, we’re very impressed with v14.1.7, and we think this is Tesla’s best iteration of the FSD suite yet, as it should be since it’s the newest version available. Tesla’s attention to detail regarding the brake stabbing is really well done, and it seems evident that a complete fix is on its way.

Other than the navigation issue at the very beginning, which was not an intervention, at least in my opinion, this was a really successful drive.

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Elon Musk debunks report claiming xAI raised $15 billion in funding round

xAI also responded with what appeared to be an automated reply, stating, “Legacy Media Lies.”

Published

6 hours ago

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November 13, 2025

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Credit: xAI

Elon Musk has debunked a report claiming his AI startup xAI had raised $15 billion from a funding round. Reports of the alleged funding round were initially reported by CNBC, which cited sources reportedly familiar with the matter.

CNBC’s report

The CNBC story cited unnamed sources that claimed that the new capital injection would help fund GPUs that xAI needs to train its large language model, Grok. The news outlet noted that following the funding round, xAI was valued at $200 billion. 

Artificial intelligence startups have been raising funds from investors as of late. OpenAI raised $6.6 billion in October, valuing the startup at a staggering $500 billion. Reuters also reported last month that OpenAI was preparing for an IPO with a valuation of $1 trillion. Elon Musk’s xAI is looking to catch up and disrupt OpenAI, as well as its large language model, ChatGPT, which has become ubiquitous.

Elon Musk and xAI’s responses

In his response on X, Elon Musk simply stated that the CNBC story was “false.” He did not, however, explain if the whole premise of the publication’s article was fallacious, or if only parts of it were inaccurate. 

Amusingly enough, xAI also issued a response when asked about the matter by Reuters, which also reported on the story. The artificial intelligence startup responded with what appeared to be an automated reply, which read, “Legacy Media Lies.”

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xAI, founded in July 2023 as an alternative to OpenAI and Anthropic, has aggressively built out infrastructure to support its flagship products, including Grok and its recently launched Grokipedia platform. The company is developing its Colossus supercomputer in Memphis, which is heralded as one of the world’s largest supercomputer clusters.

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Tesla reportedly testing Apple CarPlay integration: report

Citing insiders reportedly familiar with the matter, Bloomberg News claimed that CarPlay is being trialed by the EV maker internally.

Published

9 hours ago

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November 13, 2025

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Credit: Tesla

Tesla is reportedly testing Apple’s CarPlay software for its vehicles, marking a major shift after years of resisting the tech giant’s ecosystem. 

Citing insiders reportedly familiar with the matter, Bloomberg News claimed that CarPlay is being trialed by the EV maker internally. The move could help Tesla gain more market share, as surveys have shown many buyers consider CarPlay as an essential feature when choosing a car.

Not the usual CarPlay experience

Bloomberg claimed that Tesla’s tests involve a rather unique way to integrate CarPlay. Instead of replacing the vehicle’s entire infotainment display, Tesla’s integration will reportedly feature a CarPlay window on the infotainment system. This limited approach will ensure that Tesla’s own software, such as Full Self-Driving’s visuals, remains dominant. 

The feature is expected to support wireless connectivity as well, bringing Tesla in line with other luxury automakers that already offer CarPlay. While plans remain fluid and may change before public release, the publication’s sources claimed that the rollout could happen within months. 

A change of heart

Tesla has been reluctant to grant Apple access to its in-car systems, partly due to Elon Musk’s past criticism of the tech giant’s App Store policies and its poaching of Tesla engineers during the failed Apple Car project. Tesla’s in-house software is also deemed by numerous owners as a superior option to CarPlay, thanks to its sleek design and rich feature set.

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With Apple’s retreat from building cars and Elon Musk’s relationship with Apple for X and Grok, however, the CEO’s stance on the tech giant seems to be improving. Overall, Tesla’s potential CarPlay integration would likely be appreciated by owners, as a McKinsey & Co. survey last year found that roughly one-third of buyers considered the lack of such systems a deal-breaker.

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