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How SpaceX is able to achieve its amazing rocket landing accuracy

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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.

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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 ofΒ 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.

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 thickerΒ atmospheric conditions, the grid fins deploy and are used like wings to guide the stage down to its landing location, be that onΒ 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 droneshipΒ 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 1038Β 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 impressiveΒ that kind of accuracy is.

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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 atΒ 1,221Β°F.

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 set to get an awesome new feature, Elon Musk says

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Credit: Teslarati

Tesla Full Self-Driving is set to get an awesome new feature in the near future, CEO Elon Musk confirmed on X.

Full Self-Driving is the company’s semi-autonomous driving program, which is among the best available to the general public. It still relies on the driver to ultimately remain in control and pay attention, but it truly does make traveling less stressful and easier.

However, Tesla still continuously refines the software through Over-the-Air updates, which are meant to resolve shortcomings in the performance of the FSD suite. Generally, Tesla does a great job of this, but some updates are definitely regressions, at least with some of the features.

Tesla Cybertruck owner credits FSD for saving life after freeway medical emergency

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Tesla and Musk are always trying to improve the suite’s performance by fixing features that are presently available, but they also try to add new things that would be beneficial to owners. One of those things, which is coming soon, is giving the driver the ability to prompt FSD with voice demands.

For example, asking the car to park close to the front door of your destination, or further away in an empty portion of the parking lot, would be an extremely beneficial feature. Adjusting navigation is possible through Grok integration, but it is not always effective.

Musk confirmed that voice prompts for FSD would be possible:

Tesla Full Self-Driving is a really great thing, but it definitely has its shortcomings. Navigation is among the biggest complaints that owners have, and it is easily my biggest frustration with using it. Some of the routes it chooses to take are truly mind-boggling.

Another thing it has had issues with is being situated in the correct lane at confusing intersections or even managing to properly navigate through local traffic signs. For example, in Pennsylvania, there are a lot of stop signs with “Except Right Turn” signs directly under.

This gives those turning right at a stop sign the opportunity to travel through it. FSD has had issues with this on several occasions.

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Parking preferences would be highly beneficial and something that could be resolved with this voice prompt program. Grocery stores are full of carts not taken back by customers, and many people choose to park far away. Advising FSD of this preference would be a great advantage to owners.

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Cybertruck

Elon Musk clarifies Tesla Cybertruck ’10 day’ comment, fans respond

Some are arguing that the decision to confirm a price hike in ten days is sort of counterproductive, especially considering it is based on demand. Giving consumers a timeline of just ten days to make a big purchase like a pickup truck for $60,000, and basically stating the price will go up, will only push people to make a reservation.

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Credit: Tesla

Elon Musk has clarified what he meant by his comment on X yesterday that seemed to indicate that Tesla would either do away with the new All-Wheel-Drive configuration of the Cybertruck or adjust the price.

The response was cryptic as nobody truly knew what Musk’s plans were for the newest Tesla Cybertruck trim level. We now have that answer, and fans of the company are responding in a polarizing fashion.

On Thursday night, Tesla launched the Cybertruck All-Wheel-Drive, priced competitively at $59,990. It was a vast improvement from the Rear-Wheel-Drive configuration Tesla launched last year at a similar price point, which was eventually cancelled just a few months later due to low demand.

Tesla launches new Cybertruck trim with more features than ever for a low price

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However, Musk said early on Friday, “just for 10 days,” the truck would either be available or priced at $59,990. We can now confirm Tesla will adjust the price based on more recent comments from the CEO.

Musk said the price will fluctuate, but it “depends on how much demand we see at this price level.”

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Some are defending the decision, stating that it is simply logical to see how the Cybertruck sells at this price and adjust accordingly.

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Others, not so much.

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Some are arguing that the decision to confirm a price hike in ten days is sort of counterproductive, especially considering it is based on demand. Giving consumers a timeline of just ten days to make a big purchase like a pickup truck for $60,000, and basically stating the price will go up, will only push people to make a reservation.

Demand will look strong because people want to lock in this price. The price will inevitably go up, and demand for the trim will likely fall a bit because of the increased cost.

Many are arguing Musk should have kept this detail internal, but transparency is a good policy to have. It is a polarizing move to confirm a price increase in just a week-and-a-half, but the community is obviously split on how to feel.

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Cybertruck

Tesla Cybertruck’s newest trim will undergo massive change in ten days, Musk says

It appears as if the new All-Wheel-Drive trim of Cybertruck won’t be around for too long, however. Elon Musk revealed this morning that it will be around “only for the next 10 days.”

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(Credit: Tesla)

Tesla’s new Cybertruck trim has already gotten the axe from CEO Elon Musk, who said the All-Wheel-Drive configuration of the all-electric pickup will only be available “for the next ten days.”

Musk could mean the price, which is $59,990, or the availability of the trim altogether.

Last night, Tesla launched the All-Wheel-Drive configuration of the Cybertruck, a pickup that comes in at less than $60,000 and features a competitive range and features that are not far off from the offerings of the premium trim.

Tesla launches new Cybertruck trim with more features than ever for a low price

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It was a nice surprise from Tesla, considering that last year, it offered a Rear-Wheel-Drive trim of the Cybertruck that only lasted a few months. It had extremely underwhelming demand because it was only $10,000 cheaper than the next trim level up, and it was missing a significant number of premium features.

Simply put, it was not worth the money. Tesla killed the RWD Cybertruck just a few months after offering it.

With the news that Tesla was offering this All-Wheel-Drive configuration of the Cybertruck, many fans and consumers were encouraged. The Cybertruck has been an underwhelming seller, and this seemed to be a lot of truck for the price when looking at its features:

  • Dual Motor AWD w/ est. 325 mi of range
  • Powered tonneau cover
  • Bed outlets (2x 120V + 1x 240V) & Powershare capability
  • Coil springs w/ adaptive damping
  • Heated first-row seats w/ textile material that is easy to clean
  • Steer-by-wire & Four Wheel Steering
  • 6’ x 4’ composite bed
  • Towing capacity of up to 7,500 lbs
  • Powered frunk

It appears as if this trim of Cybertruck won’t be around for too long, however. Musk revealed this morning that it will be around “only for the next 10 days.”

Musk could mean the price of the truck and not necessarily the ability to order it. However, most are taking it as a cancellation.

If it is, in fact, a short-term availability decision, it is baffling, especially as Tesla fans and analysts claim that metrics like quarterly deliveries are no longer important. This seems like a way to boost sales short-term, and if so many people are encouraged about this offering, why would it be kept around for such a short period of time?

Some are even considering the potential that Tesla axes the Cybertruck program as a whole. Although Musk said during the recent Q4 Earnings Call that Cybertruck would still be produced, the end of the Model S and Model X programs indicates Tesla might be prepared to do away with any low-volume vehicles that do not contribute to the company’s future visions of autonomy.

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The decision to axe the car just ten days after making it available seems like a true head-scratcher.

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