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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 brings Model Y L ‘Launch Series’ to the U.S. at $61,990

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Tesla has officially launched the Model Y L in the United States and Puerto Rico for $61,990. It is the longer-wheelbase version of the Model Y, and has been available in China since last year.

Tesla brings the Model Y L to the U.S. just months after it phased out the only pure SUV in its lineup, the Model X. It is slightly longer than the Model Y configurations that are already available in the U.S., and features a three-row, six-seat setup with Captain’s Chairs being among the many features that make this a truly fantastic offering.

The Model Y L is priced competitively at $61,990, and features 325 miles of range and a 0-60 MPH in just 4.4 seconds.

Tesla also added a handful of new features that are not available in even the Premium Model Y. Here’s a full list of its features:

  • Heated/Ventilated Front Seats with Powered Thigh Cushion
  • Heated/Ventilated Captain’s Seats in Second Row with Powered Armrests & One-Touch Fold
  • Heated Third-Row Seats with Power Recline, One-Touch Fold & Child Seat Anchors
  • Improved Airflow, Increased Efficiency, More Range
  • 89 cubic feet of trunk space
  • Upgraded Acoustic Glass and Suspension to Minimize Road Noise
  • Adaptive Damping for a Smooth, Stable Ride
  • Staggered Tires for Enhanced Grip
  • Larger Tailgate for Better Rear Visibility and Bigger Windows Overall
  • 16″ First Row and 8″ Second Row Touchscreens
  • 19-Speaker Immersive Tesla Audio
  • 50W Wireless Charging Pads with Active Cooling and Charging Ports for All Other Seats
  • FSD Supervised and Integrated Grok AI

Tesla is also delivering these first units as a “Launch Series,” which comes with additional features, such as:

  • Door Trim Puddle Lights
  • Suede Dashboard Wing
  • Exterior and Interior Badging
  • Floor Mats
  • Sill Plates

The launch of the Model Y L in the U.S. marks a huge offering from Tesla to U.S. consumers. People have been calling for Tesla to bring a larger car to the U.S., and it needed it more than ever now that the Model X is gone.

It is a huge accomplishment for Tesla to get the Model Y L to the U.S., and after reporting strong deliveries today, it will be interesting to see how this car impacts future quarterly delivery reports.

Deliveries for the Model Y L “Launch Series” are slated for September or October of this year.

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Tesla just told us twice that Model Y L is coming to the U.S.

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Credit: Tesla

Tesla just told us twice that the Model Y L is coming to the U.S., and two social media posts definitely just tipped the company’s hand, as if they wanted it to be any other way.

The two social media posts basically confirm that the slightly longer version of the Model Y will be heading to the United States soon, and many have speculated that the company could launch the vehicle as soon as this weekend.

The first post was directly from Tesla, and it showed an incredibly long Dachshund, with words above that said, “Looking forward to the long weekend.”

Anyone who knows Tesla knows the company loves to troll its fans and have fun, and this is a perfect example of that. While not a direct acknowledgement, Tesla is very involved on social media, especially CEO Elon Musk’s platform X, and the company is well aware of what is being discussed within the community.

With recent sightings of Model Y L test mules in California, peeks of the vehicle at Giga Texas, and a large call for the car to come to the U.S., Tesla is simply stoking conversation with this.

However, the company also made another move that was recognized on social media. Tesla has a large gallery that includes photos of its products so media and others can use them. This gallery applies to the U.S. market specifically, unless otherwise specified.

Tesla uploaded a Model Y L to the Gallery last night:

This seems to be another indication that the Model Y L is coming to the United States.

Musk said last year that the Model Y L could make its way to the United States late this year, but it was not something that was set in stone by Tesla. The company definitely needs to establish something in the SUV market that is larger than the Model Y, and the Model Y L might be the answer.

Even still, there are consumers out there who would love Tesla to develop something even larger, like a competitor to the Tahoe or Expedition. Tesla has not really given much of an indication that it will go in that direction.

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Tesla is using vehicle microphones to improve build quality: here’s how

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Credit: Tesla

Tesla is using the vehicles’ internal microphones to improve build quality, Vice President of Engineering Lars Moravy revealed recently.

It’s no secret that Tesla is always finding ways to make its manufacturing operations more efficient, accurate, and valuable. Constantly trying to make its cars better, the company has never placed any restrictions on what it will do to improve everything from panel gaps to paint.

As Teslas have been driving autonomously on the property of the Gigafactory Texas plant for a while now, Moravy revealed to Herbert Ong in a new interview that cars rolling off production lines now autonomously navigate themselves through a bumps, squeaks, and rattles (BSR) portion of the line. This helps to identify any loose or improperly installed internal parts.

The cabin’s microphones, which are used for a variety of things in ownership, simultaneously monitor any noises inside the vehicle while it rolls through the BSR portion of the production line. Moravy actually revealed that Tesla is trying to build “Full Self-Hearing,” an AI system that will detect minor imperfections so they can be corrected before delivery.

It’s no secret that build quality is something that Tesla struggled with as it scaled to a fully massive production operation that manufactures over 1.6 million vehicles per year. However, in recent years, especially, there have not been as many complaints. Tesla has truly improved upon its build quality and paint quality over the past several years, especially in the U.S.

Tesla’s ‘megacasts’ are key to massive build quality improvements

While those improvements have been evident, there are still some complaints; no automaker is perfect with this. But this step will now ensure that every single car that rolls off the production lines at Gigafactory Texas will be void of any creaks, squeaks, or squeals when it leaves the factory.

This measure is one of the most unique we’ve seen in terms of a strategy to avoid build quality issues, but it is not exclusive to Tesla.

Ford uses acoustic analysis AI to find abnormalities in seat motors, climate control units, and other components. Suppliers and OEMs will also use microphone arrays or particle velocity sensors in end-of-line stations.

The full interview with Lars Moravy is available below:

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