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SpaceX scrubs Starhopper’s final Raptor-powered flight as Elon Musk talks “finicky” igniters

SpaceX scrubbed Starhopper's second flight test on August 26th. Another attempt will follow on the 27th. (SpaceX)

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For unknown reasons, SpaceX’s Starhopper prototype suffered a hold just 0.8 seconds prior to its second planned flight test, a hold that was eventually followed by a decision to scrub the August 26th attempt and try again tomorrow, August 27th.

Starhopper is a full-scale, partial-height testbed for SpaceX’s next-generation Starship launch vehicle, serving more as a semi-mobile test stand for steel rockets and Raptor engines than an actual Starship prototype. The unusual vehicle took flight for the first time ever on July 25th, reaching an altitude of roughly 20m (65 ft) under the power of a single Raptor engine, capable of producing up to 200 tons (450,000 lbf) of thrust. That test also suffered a minor scrub on the 24th, followed by a successful flight one day later, a chapter that Starhopper may now mirror on its second attempted flight, a 150m (500 ft) hop.

Notably, SpaceX CEO Elon Musk took to Twitter just seconds after the rocket’s scheduled liftoff suffered a last-second hold to indicate that Raptor’s torch igniters were proving somewhat finicky relative to the chemical alternative used by SpaceX’s proven Merlin engines.

The CEO later confirmed that that comment was directly related to the 26th’s scrub, indicating that Raptor serial number 06 (SN06) needed to have its igniters inspected prior to a second hop test attempt, now scheduled to occur no earlier than 6pm EDT (22:00 UTC) on August 27th. The gist of the difficulties with Raptor’s igniter starts with the reason that SpaceX is attempting to integrate an entirely new form of ignition into the engine, replacing the methods successfully used over tens or even hundreds of thousands of seconds of firing with the company’s Merlin 1 and Merlin Vacuum engines.

Merlin 1D and MVacD both rely on a relatively simple, reliable, cheap, and easy method of chemical ignition, using a duo of pyrophoric materials known as triethylaluminum-triethylborane (TEA-TEB). When mixed, these materials immediately combust, generating an iconic green flash visible during Falcon 9 and Heavy launches, and thus producing the ‘spark’ needed to start Merlin engines.

Falcon 9 and Heavy use chemical means – TEA-TEB – to ignite all of their main and upper stage Merlin engines. (SpaceX)

Generally speaking, TEA-TEB is an excellent method of igniting rockets, even if it is more of a brute-force, inelegant solution than alternatives. It does, however, bring limitations: every single ignition requires a new ‘cartridge’ be expended, fundamentally limiting the number of times Merlin 1D (and Merlin Vacuum) engines can be ignited before and after liftoff.

This doesn’t even consider the fact that TEA-TEB are extremely complex chemical products that would be next to impossible to produce off of Earth, at least for the indefinite future.

To combat these downsides, SpaceX has designed Raptor with an entirely different method of ignition, known as torch ignition. Technically speaking, Raptor’s power, design, and methalox propellant combine to demand more than a relatively common solution, in which spark plugs are used to ignite an engine. Instead, Raptor uses those spark plugs to ignite its ignition sources, what CEO Elon Musk has described as full-up blow torches. Once ignited, those blow torches – likely miniature rocket engines using the same methane and oxygen fuel as Raptor – then ignite the engine’s methane and oxygen preburners before finally igniting those mixed, high-pressure gases in the combustion chamber.

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In simple terms, the fact that Raptor is a full-flow staged-combustion (FFSC) engine means that the pressures it must operate under are extreme, verging on unprecedented in large-scale rocketry. Extremely high-pressure gases (on the order of 3,000-10,000+ psi or 200-700+ bar) are just as difficult to reliably ignite, especially if hypergolic solutions (i.e. TEA-TEB) are off the table.

To get an even ignition – critical to avoid burn-through, minor explosions, and even catastrophic engine failures – Raptor’s torch ignition may actually involve a 360-degree ring of spark plug-lit torches around the point of ignition, an undeniably complex solution.

The first finalized Raptor engine (SN01) completed a successful static fire debut on the evening of February 3rd. (SpaceX)

However, as Musk notes, these significant, “finicky” challenges brought on by Raptor’s exotic ignition method are motivated by the potential benefits such a solution might bring. Relative to Merlin 1D’s TEA-TEB ignition, torch ignition – once optimized and matured into a reliable solution – will permit an almost unlimited number of Raptor ignitions before, during, and after flight.

Avoiding TEA-TEB and other complex chemical igniters also means that Starship will technically be able to launch to Mars or the Moon, perform injection and landing burns, maybe even hop around the surface, and still be able to return to Earth – all without resupply. Such a return voyage would still be predicated on the ability to generate the methane and oxygen propellant needed to fuel Starships, but – assuming that challenge can be solved – torch-lit Raptors would be ready for such a mission. In the event that, say, something like August 26th’s scrub happens to a Starship on Mars, the crew would also be able to get out, inspect Starship’s Raptors, and even replace faulty spark plugs if necessary.

For Starship to remain readily reusable in either of these situations, Raptor’s use of torch ignition will be absolutely critical. (SpaceX)

Technically, one could bring lots of spare TEA-TEB cartridges and install those in space or after landing, but those cartridges are quite literally firebombs waiting to ignite, whereas spare spark plugs are entirely inert.

For now, we’ll have to wait for SpaceX technicians to get their eyes and hands-on Starhopper’s lone Raptor engine to verify that its ignition hardware is in good health. If all goes well, Starhopper will attempt its final flight test as early as August 27th.

Update (August 27th): Starhopper is reportedly set for a second attempted 150m (500 ft) flight test today, scheduled to occur no earlier than 5pm EDT (21:00 UTC) on August 27th. Stay tuned for SpaceX’s official Livestream!

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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 confirms Full Self-Driving still isn’t garnering interest from lagging competitors

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Credit: Tesla

Tesla executive Sendil Palani confirmed in a post on social media platform X that Full Self-Driving, despite being the most robust driver assistance program in the United States, still isn’t garnering any interest from lagging competitors.

Tesla has said on several occasions in the past that it has had discussions with a competing carmaker to license its Full Self-Driving suite. While it never confirmed which company it was, many pointed toward Ford as the one Tesla was holding dialogue with.

At the time, Ford CEO Jim Farley and Tesla CEO Elon Musk had a very cordial relationship.

Despite Tesla’s confirmation, which occurred during both the Q2 2023 and Q1 2024 Earnings Calls, no deal was ever reached. Whichever “major OEM” Tesla had talked to did not see the benefit. Even now, Tesla has not found that dance partner, despite leading every company in the U.S. in self-driving efforts by a considerable margin.

Elon Musk says Tesla Robotaxi launch will force companies to license Full Self-Driving

Palani seemed to confirm that Tesla still has not found any company that is remotely interested in licensing FSD, as he said on X that “despite our best efforts to share the technology,” the company has found that it “has not been proven to be easy.”

The question came just after one Tesla fan on X asked whether Tesla would continue manufacturing vehicles.

Because Tesla continues to expand its lineup of Model Y, it has plans to build the Cybercab, and there is still an immediate need for passenger vehicles, there is no question that the company plans to continue scaling its production.

However, Palani’s response is interesting, especially considering that it was in response to the question of whether Tesla would keep building cars.

Perhaps if Tesla could license Full Self-Driving to enough companies for the right price, it could simply sell the suite to car companies that are building vehicles, eliminating the need for Tesla to build its own.

While it seems like a reach because of Tesla’s considerable fan base, which is one of the most loyal in the automotive industry, the company could eventually bail on manufacturing and gain an incredible valuation by simply unlocking self-driving for other manufacturers.

The big question regarding why Tesla can’t find another company to license FSD is simply, “Why?”

Do they think they can solve it themselves? Do they not find FSD as valuable or effective? Many of these same companies didn’t bat an eye when Tesla started developing EVs, only to find themselves years behind. This could be a continuing trend.

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Tesla exec pleads for federal framework of autonomy to U.S. Senate Committee

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Credit: Tesla

Tesla executive Lars Moravy appeared today in front of the U.S. Senate Commerce Committee to highlight the importance of modernizing autonomy standards by establishing a federal framework that would reward innovation and keep the country on pace with foreign rivals.

Moravy, who is Tesla’s Vice President of Vehicle Engineering, strongly advocated for Congress to enact a national framework for autonomous vehicle development and deployment, replacing the current patchwork of state-by-state rules.

These rules have slowed progress and kept companies fighting tooth-and-nail with local legislators to operate self-driving projects in controlled areas.

Tesla already has a complete Robotaxi model, and it doesn’t depend on passenger count

Moravy said the new federal framework was essential for the U.S. to “maintain its position in global technological development and grow its advanced manufacturing capabilities.

He also said in a warning to the committee that outdated regulations and approval processes would “inhibit the industry’s ability to innovate,” which could potentially lead to falling behind China.

Being part of the company leading the charge in terms of autonomous vehicle development in the U.S., Moravy highlighted Tesla’s prowess through the development of the Full Self-Driving platform. Tesla vehicles with FSD engaged average 5.1 million miles before a major collision, which outpaces that of the human driver average of roughly 699,000 miles.

Moravy also highlighted the widely cited NHTSA statistic that states that roughly 94 percent of crashes stem from human error, positioning autonomous vehicles as a path to dramatically reduce fatalities and injuries.

Skeptics sometimes point to cybersecurity concerns within self-driving vehicles, which was something that was highlighted during the Senate Commerce Committee hearing, but Moravy said, “No one has ever been able to take over control of our vehicles.”

This level of security is thanks to a core-embedded central layer, which is inaccessible from external connections. Additionally, Tesla utilizes a dual cryptographic signature from two separate individuals, keeping security high.

Moravy also dove into Tesla’s commitment to inclusive mobility by stating, “We are committed with our future products and Robotaxis to provide accessible transportation to everyone.” This has been a major point of optimism for AVs because it could help the disabled, physically incapable, the elderly, and the blind have consistent transportation.

Overall, Moravy’s testimony blended urgency about geopolitical competition, especially China, with concrete safety statistics and a vision of the advantages autonomy could bring for everyone, not only in the U.S., but around the world, as well.

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Tesla Model Y lineup expansion signals an uncomfortable reality for consumers

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Credit: Tesla

Tesla launched a new configuration of the Model Y this week, bringing more complexity to its lineup of the vehicle and adding a new, lower entry point for those who require an All-Wheel-Drive car.

However, the broadening of the Model Y lineup in the United States could signal a somewhat uncomfortable reality for Tesla fans and car buyers, who have been vocal about their desire for a larger, full-size SUV.

Tesla has essentially moved in the opposite direction through its closure of the Model X and its continuing expansion of a vehicle that fits the bill for many, but not all.

Tesla brings closure to Model Y moniker with launch of new trim level

While CEO Elon Musk has said that there is the potential for the Model Y L, a longer wheelbase configuration of the vehicle, to enter the U.S. market late this year, it is not a guarantee.

Instead, Tesla has prioritized the need to develop vehicles and trim levels that cater to the future rollout of the Robotaxi ride-hailing service and a fully autonomous future.

But the company could be missing out on a massive opportunity, as SUVs are a widely popular body style in the U.S., especially for families, as the tighter confines of compact SUVs do not support the needs of a large family.

Although there are other companies out there that manufacture this body style, many are interested in sticking with Tesla because of the excellent self-driving platform, expansive charging infrastructure, and software performance the vehicles offer.

Additionally, the lack of variety from an aesthetic and feature standpoint has caused a bit of monotony throughout the Model Y lineup. Although Premium options are available, those three configurations only differ in terms of range and performance, at least for the most part, and the differences are not substantial.

Minor Expansions of the Model Y Fail to Address Family Needs for Space

Offering similar trim levels with slight differences to cater to each consumer’s needs is important. However, these vehicles keep a constant: cargo space and seating capacity.

Larger families need something that would compete with vehicles like the Chevrolet Tahoe, Ford Expedition, or Cadillac Escalade, and while the Model X was its largest offering, that is going away.

Tesla could fix this issue partially with the rollout of the Model Y L in the U.S., but only if it plans to continue offering various Model Y vehicles and expanding on its offerings with that car specifically. There have been hints toward a Cyber-inspired SUV in the past, but those hints do not seem to be a drastic focus of the company, given its autonomy mission.

Tesla appears to be mulling a Cyber SUV design

Model Y Expansion Doesn’t Boost Performance, Value, or Space

You can throw all the different badges, powertrains, and range ratings on the same vehicle, it does not mean it’s going to sell better. The Model Y was already the best-selling vehicle in the world on several occasions. Adding more configurations seems to be milking it.

The true need of people, especially now that the Model X is going away, is going to be space. What vehicle fits the bill of a growing family, or one that has already outgrown the Model Y?

Not Expanding the Lineup with a New Vehicle Could Be a Missed Opportunity

The U.S. is the world’s largest market for three-row SUVs, yet Tesla’s focus on tweaking the existing Model Y ignores this. This could potentially result in the Osborne Effect, as sales of current models without capturing new customers who need more seating and versatility.

Expansions of the current Model Y offerings risk adding production complexity without addressing core demands, and given that the Model Y L is already being produced in China, it seems like it would be a reasonable decision to build a similar line in Texas.

Listening to consumers means introducing either the Model Y L here, or bringing a new, modern design to the lineup in the form of a full-size SUV.

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