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SpaceX CEO Elon Musk talks Starship explosion: “We were too dumb”

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Two days after a last-second failure caused Starship SN9 to smash into the ground and explode, SpaceX CEO Elon Musk has returned to Twitter with some harsh preliminary reactions.

Right off the bat, in response to a question about why Starships SN8 and SN9 both attempted their unsuccessful landings with only two of three available Raptor engines, Musk frankly stated that “we were too dumb.” At face value, it’s a decent question, given that there are no obvious showstoppers to explain why Starships couldn’t make the most of the redundancy their three Raptor engines can offer.

After completing an otherwise flawless 6.5 minutes launch, ascent, and belly-flop descent, Starship SN9 began a critical ~120-degree flip maneuver, sequentially igniting two Raptor engines and using that thrust to flip from a belly-down attitude to a tail-first landing configuration. Unfortunately, though the first Raptor did fire up and put in a good effort, the second engine failed to ignite, leaving the building-sized rocket to impact the ground traveling far too quickly.

Ironically, more than three years ago, Musk himself revealed in a Reddit Ask Me Anything thread that he and his engineers had decided to modify Starship’s (then known as BFS) design by adding a third Raptor to its central cluster of two engines.

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“Btw, we modified the [Starship] design since IAC [2017] to add a third medium-area-ratio Raptor engine partly for that reason (lose only 1/3 thrust in engine out) and allow landings with higher payload mass for the Earth to Earth transport function.”

Elon Musk – Reddit AMA – October 2017

Primarily meant to enable more efficient landings in Earth’s atmosphere, adding a third engine to that cluster would logically increase the chances of a successful (or at least survivable) landing in the event that one engine fails. Greater thrust and an improved thrust-to-weight ratio both during launch and landing would fundamentally improve the efficiency of Starship, likely making up for most or all of the added weight.

Starship SN9 lifted off with three Raptors but attempted to land with two. According to Elon Musk, that may have been an oversight. (SpaceX)
Back in 2017, BFS featured two smaller-nozzle Raptors, whereas SpaceX eventually side on three (and three Raptor Vacuum variants) for Starship. (SpaceX)
Ironically, the original ‘Starship’ (ITS) also featured a cluster of three central landing engines. (SpaceX)

In retrospect, it’s not entirely surprising to learn that a three-engine landing burn is probably the most logical option if three landing-class engines have been included in the design. In SpaceX and Musk’s defense, however, there are also several good reasons to use as few Raptor engines as possible.

Throttling high-performance rocket engines is exceptionally difficult and Raptor is not yet a fully mature engine, meaning that it’s throttle capabilities are likely less than optimal. That’s relevant because the higher a rocket’s thrust-to-weight ratio during landing, the more aggressive its landings have to be. SpaceX is apparently extremely conservative with Starship in this regard, prioritizing slow, gentle landings by only using two of three available engines.

Ironically, it’s possible that that attempt at risk reduction resulted in harder landings for both Starship SN8 and SN9, as three-engine landing burns could have potentially slowed them down significantly more before impact.

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At the same time, though it may have mitigated the severity of both landing failures, three-engine landing burns would not have resolved the fundamental issues that caused them. In SN8’s case, low fuel header tank pressure doomed the Starship, while SN9 is more ambiguous. Aside from the clear Raptor ignition failure, which a three-engine burn could have resolved by downselecting to two healthier engines, the one Raptor that did ignite appeared to suffer some kind of uncontained failure seconds before landing.

Impressively, despite that apparent combustion chamber or preburner failure, the engine’s landing burn seemed to continued uninterrupted until the moment of impact. As such, it’s hard to say if that lone Raptor was still producing substantial thrust or if it was in the throes of a catastrophic failure. If it could have held on for another 5-10 seconds and the third Raptor (the engine that didn’t reignite) was able to restart and perform without issue, a three-engine landing burn could have easily made SN9’s demise less violent or even have enabled a soft landing.

While a three-engine burn all the way to touchdown appears to be extremely risky or impossible for present-day Starships, Musk implied that there was nothing preventing SpaceX from reigniting all three engines during the initial flip and landing burn and using that time to determine the health of all three engines. If all three were healthy, Starship would shut down one for a soft landing. If one engine failed to restart or lost thrust shortly after ignition, the other two would already be active and able to take over.

Musk says that Starship SN10, already at the launch pad and likely days away from its first tests, will attempt to adopt that approach on an upcoming test flight expected as few as 2-3 weeks from now.

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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 reveals huge Cybercab detail in new guide for First Responders

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Credit: Tesla

Tesla revealed a major new Cybercab detail in a guide it released for First Responders, showing new territory in its beliefs and intentions for the ride-hailing-focused vehicle that entered production in April.

The First Responders Guide is released to give fire departments, paramedics, and other emergency personnel the proper guidance on what to do in the event of an accident, entrapment, or other situation that would require immediate attention.

On one of the pages of the First Responders Guide, Tesla revealed a stark detail about the Cybercab, which could help personnel enter the vehicle more easily in case of an emergency.

Tesla Cybercab has one important piece that AI4 cars might need for FSD

It shows Tesla has no intention of releasing any Cybercab units that were initially proposed for ride-hailing services for the general public with any manual controls, meaning a steering wheel or pedals:

“A Cybercab equipped with steering wheel, brake pedal, and an acceleration pedal is typically an engineering or test vehicle, and operates at SAE Level 2 autonomy. Cybercab is not typically equipped with a steering wheel or acceleration and brake pedals.”

This is a major development for those who continue to believe Tesla planned to release the Cybercab with any sort of manual controls so that passengers could take over if needed. However, when Tesla started manufacturing production versions of the Cybercab in Giga Texas earlier this year, they were spotted without a steering wheel or pedals.

It essentially confirms the company has no intentions of bringing manual controls to the car’s production versions. Some have argued that the likelihood of Tesla having something

There still are some Cybercab units out there with a steering wheel and pedals, and as Tesla said, these cars are engineering or test vehicles, which have Safety Monitors on board to help the car out of a precarious situation or emergency.

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Tesla Full Self-Driving v14 ‘Lite’ Release Notes: new capabilities and features

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(Credit: Megan Gale/Twitter)

Tesla released the Full Self-Driving v14 ‘Lite’ suite to owners of Hardware 3 or AI3 vehicles today, adding several new features to the vehicles that were once believed to be capable of unsupervised self-driving.

Now, Tesla has released this modified suite to older Tesla vehicles, adding plenty of new features and capabilities.

Here are the full release notes for the suite:

  • Distilled the intelligence from HW4 V14 into HW3. This allows HW3 to directly learn how to handle scenarios using HW4 V14 as a guide. This process unlocks the improvements that have been made to HW4 including Reinforcement Learning (RL) and offline models for HW3.
  • Improved both proactive and reactive responsiveness across a wide variety of categories including navigation handling, merges and forks, pedestrian interactions, traffic lights, and vehicle cut-in scenarios.
  • Improved general comfort in nominal scenarios through fewer false slowdowns, smoother steering and more consistent lane centering.
  • Introduced parking, unparking, and reversing capabilities.
  • Added Arrival Options for you to select where FSD should park: in a Parking Lot, on the Street, in a Driveway, or at the Curbside.
  • Speed Profiles are now available at all times, to further customize driving style preference.

These improvements, according to Tesla’s Head of AI, Ashok Elluswamy, help distill the driving behavior from AI4’s v14 series into both the camera and compute configurations of AI3.

Tesla Full Self-Driving v14 ‘Lite’ for older cars finally gets released

He added:

“It includes destination options and speed profiles on city roads, but more importantly significantly improved safety. We hope you’ll enjoy it, once the build ships wide.”

Tesla will continue to roll out the v14 Lite suite more widely in the coming weeks, the company said.

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Tesla Full Self-Driving v14 ‘Lite’ for older cars finally gets released

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tesla model 3 model y
Credit: Tesla Inc.

Tesla has finally released its Full Self-Driving v14 ‘Lite’ suite for older cars that equip the Hardware 3 or AI 3 chip, which have not been able to handle the newest versions of the company’s driver assistance software.

Tesla officially started releasing the v14 Lite suite to owners in the Early Access Program last night. The company’s Head of AI, Ashok Elluswamy, said that the rollout will continue over the next few weeks. The build distills the driving behavior from AI4’s v14 series into both the camera and compute configurations of an AI3 car.

It also includes a variety of new features that were available to AI4 cars running v14, including:

  • Start Self-Driving from Park
  • Arrival and Parking Options
  • Speed Profiles

The release is highly anticipated because those owners with AI3 vehicles were early adopters into the FSD platform and were promised that their cars would be capable of achieving Full Self-Driving.

However, Tesla CEO Elon Musk admitted during the company’s recent Q1 Earnings Call that these vehicles would not be capable of achieving unsupervised Full Self-Driving, which is what Tesla had originally said.

Owners were not pleased with this answer, or the idea that their commitment to buying the suite outright for thousands of dollars would not yield the ability to drive without operating the car. Tesla gave some solutions for this, including a discount on a new car, or an upgrade to an AI4 or AI5 self-driving computer and new, upgraded cameras.

Tesla owners do not seem pleased with these options, as they require giving the company more money.

Nevertheless, it is important to note that Tesla came through for owners here by releasing v14 Lite before the end of Q2, something it had promised owners during the previous Earnings Call. Tesla has had trouble keeping up with timelines, but this is a big achievement for the team.

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