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SpaceX delays Starhopper’s first flight a few days despite Raptor preburner test success

According to NASASpaceflight.com, SpaceX's Starhopper successfully completed a Raptor preburner taste on July 15th. A static fire ignition test should follow on July 16th.(NASASpaceflight - bocachicagal)

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SpaceX has (partially) ignited Starhopper’s freshly-installed Raptor engine, successfully verifying that the engine is ready for its next major test: a full ignition and static firing. Although successful, SpaceX still has some work to do before the vehicle is ready for its first untethered flight(s).

July 15th’s progress is just the latest in a several day-series of preflight tests designed to reduce the likelihood that Starhopper is destroyed over the coming days and (hopefully) weeks. If all goes planned during the awkward Starship prototype’s first foray into hover tests, SpaceX CEO Elon Musk has stated that he will provide an official presentation updating the public on the status of the company’s ever-changing next-generation rocket.

The past week or so of Starhopper preflight testing began with Raptor serial number 6 (SN06) completing the last of a series of acceptance test fires in McGregor, Texas on June 10th. Even on its own, this was a major milestone for the new SpaceX engine: Raptor SN06 was the first of the new, full-scale engines to pass the acceptance test program with flying colors. According to Musk, for the engine to complete those tests so successfully, SpaceX had to solve a challenging bug in which some sort of mechanical resonance (i.e. vibration) damaged or destroyed Raptors SN01-05.

Hours later, the engine began a short ~450 mi (720 km) journey south to Starhopper, located in Boca Chica, Texas. The engine arrived on July 11th and was fully installed on Starhopper by the following evening (July 12th), at which point SpaceX put Starhopper and Raptor through some mild but valuable thrust vector controller (TVC) tests, wiggling the car-sized engine to ensure it can accurately steer the prototype rocket.

Around two days after the above ‘wiggle’ test was successfully completed, SpaceX moved into the next stage, partially fueling Starhopper with liquid methane and oxygen propellant and helium pressurant in what is known in rocketry as a wet dress rehearsal (WDR). The (implicitly) successful WDR was capped off with a duo of what can now safely be concluded were some sort of Raptor test preceding even pre-ignition operations. Whatever the tests were, they appear to have been completed successfully.

That appears to be the case because less than 24 hours after their completion, on July 15th, SpaceX once again began loading Starhopper with propellant and pressurant for a second round of wet testing. This time around, SpaceX got right into more critical Raptor tests once enough propellant was loaded, igniting the engine’s interwoven oxygen and methane preburners.

Starhopper (technically) came alive for the third time ever on July 15th, albeit only partially. SpaceX ignited the engine’s preburners as a precursor to a full static fire, now NET July 16th. (LabPadre – YouTube livestream)

Previously discussed 24 hours ago in a Teslarati article focused on Raptor wiggles and other miscellaneous tests, Raptor is an extremely advanced rocket engine based on a cycle (i.e. how propellant is turned into thrust) known as full-flow staged combustion.

In a staged-combustion engine like Raptor, getting from the supercool liquid oxygen and methane propellant to 200+ tons of thrust is quite literally staged, meaning that the ignition doesn’t happen all at once. Rather, the preburners – essentially their own, unique combustion chambers – ignite an oxygen- or methane-rich mixture, the burning of which produces the gas and pressure that powers the turbines that bring fuel into the main combustion chamber. That fuel then ignites, producing thrust as they exit the engine’s bell-shaped nozzle.

Unintuitively, conditions inside the preburner – hidden away from view – are actually far more intense than the iconic blue, purple, and pink flame that visibly exists Raptor’s nozzle. Much like hot water will cool while traveling through pipes, the superheated gaseous propellant that Raptor ignites to produce thrust will also cool (and thus lose pressure) as it travels from Raptor’s preburner to its main combustion chamber. If the pressure produced in the preburners is too low, Raptor’s thrust will be (roughly speaking) proportionally limited at best. At worst, low pressure in the preburners can trigger a “hard start” or shutdown that could destroy the engine. According to Elon Musk, Raptor’s oxygen preburner thus has the worst of it, operating at pressures as high or higher than 800 bar (11,600 psi, 80 megapascals).”

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In full-flow staged combustion (FFSC), even more complexity is added as all propellant that touches the engine must necessarily end up traveling through the main combustion chamber to eke every last ounce of thrust out of the finite propellant a rocket lifts off with. As such, FFSC engines can be about as efficient as the laws of physics allow any given chemical rocket engine to be, at the cost of exceptional complexity and brutally difficult development.

Additionally, FFSC physically requires two separate preburners and then makes things even harder by making each separate preburner (methane and oxygen) depend on each other’s operation for the engine to fully ignite. This means that no individual preburner can be used to kickstart Raptor – instead, SpaceX must somehow spin the turbopumps that feed propellant into each preburner with some separate system. This is all just to emphasize the fact that Raptor’s ignition sequence is a spectacularly complex orchestra of valves, spark plugs, sensors, and magic. This is why it’s valuable for Raptor to test its preburner system independently of an actual ignition test, at least as long as the engine is still in the development stages.

A Raptor engine is pictured here during a static fire test in McGregor, Texas. (SpaceX)

According to NASASpaceflight.com managing editor Chris Bergin, what this practically translates to is a minor Starhopper hover test delay of 1-2 days, while the static fire has also been pushed roughly 24 hours from July 15th to July 16th. If that full static fire produces lots of happy data, Starhopper could be cleared for a hover test debut attempt as early as Wednesday or Thursday (July 17/18).

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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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