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SpaceX wiggles Starhopper’s Raptor engine, tests parts ahead of hover test debut
On the evening of July 12th, SpaceX technicians put Starhopper’s freshly-installed Raptor – serial number 06 (SN06) – through a simple but decidedly entertaining test, effectively wiggling the engine in circles.
Designed to verify that Raptor’s thrust vectoring capabilities are in order and ensure that Starhopper and the engine are properly communicating, the wiggle test is a small but critical part of pre-flight acceptance and a good indicator that the low-fidelity Starship prototype is nearing its first hover test(s). Roughly 48 hours after a successful series of wiggles, Starhopper and Raptor proceeded into the next stage of pre-flight acceptance, likely the final more step before a tethered static fire.
Routine for all Falcon rockets, SpaceX’s exceptionally rigorous practice of static firing all hardware at least once (and often several times) before launch has unsurprisingly held firm as the company proceeds towards integrated Starhopper and Starship flight tests. Despite the fact that Raptor SN06 completed a static fire as recently July 10th, SpaceX will very likely put Starhopper and its newly-installed Raptor through yet another pre-flight static fire, perhaps its fourth or fifth test this month.
Although it would undoubtedly be easier, cheaper, and faster to skip that post-delivery static fire, it will simultaneously lower the risk of Raptor failing mid-flight and verify that Starhopper itself is healthy and ready for untethered hovering. Although SpaceX could likely live without Starhopper in the event that it’s lost during flight-testing, any failure capable of destroying the vehicle itself is at least as capable of severely damaging or completely destroying the spartan but still expansive test and launch facilities the company built over the course of several months.
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Follow July 12th’s nighttime Raptor wiggle test, July 13th was mainly quiet and filled with inspections of Starhopper, Raptor, and other various work. The day after, however, SpaceX proceeded through several hours of propellant loading, ending with what looked like less energetic versions of the Raptor preburner ignition tests Starhopper previously performed with Raptor SN02.
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.
Although the fireworks are so subtle that they are easily missed, the conditions inside the preburner – hidden away from view – are actually far more intense than the iconic blue, purple, and pink flame that exists Raptor’s nozzle. This is because the preburners have to nurture the conditions necessary for the pumps they power to fuel the main combustion chamber. 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 the main combustion chamber.
Thus, if the head 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 completely prevent Raptor from starting and running stably and can even trigger a “hard start” or shutdown that could damage or destroy the engine. As such, to preburners fundamentally have to operate at higher chamber pressures (and thus higher temperatures) than the main combustion chamber (the big firey bit at the end). According to Elon Musk, Raptor’s oxygen preburner has the worst of it, operating at pressures as high or higher than 800 bar (11,600 psi, 80 megapascals).
Coincidentally, this is roughly equivalent to the pressure at the bottom of the Pacific Ocean.
In short, preburner testing is no less critical than full-on static fire testing with an engine like Raptor. July 14th’s test was also made doubly efficient due to the fact that preburner testing requires liquid propellant, which effectively makes the whole test a wet dress rehearsal (WDR) even before any engine ignition or partial ignition is involved. Per SpaceX moving from propellant loading to preburner/turbine testing, Starhopper is almost certainly healthy and operating as expected, an excellent sign that the ungainly vessel may be ready for a static fire of Raptor as early as 2pm CT, July 15th.
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Elon Musk
Starlink restrictions are hitting Russian battlefield comms: report
The restrictions have reportedly disrupted Moscow’s drone coordination and frontline communications.
SpaceX’s decision to disable unauthorized Starlink terminals in Ukraine is now being felt on the battlefield, with Ukrainian commanders reporting that Russian troops have struggled to maintain assault operations without access to the satellite network.
The restrictions have reportedly disrupted Moscow’s drone coordination and frontline communications.
Lt. Denis Yaroslavsky, who commands a special reconnaissance unit, stated that Russian assault activity noticeably declined for several days after the shutdown. “For three to four days after the shutdown, they really reduced the assault operations,” Yaroslavsky said.
Russian units had allegedly obtained Starlink terminals through black market channels and mounted them on drones and weapons systems, despite service terms prohibiting offensive military use. Once those terminals were blocked, commanders on the Ukrainian side reported improved battlefield ratios, as noted in a New York Post report.
A Ukrainian unit commander stated that casualty imbalances widened after the cutoff. “On any given day, depending on your scale of analysis, my sector was already achieving 20:1 (casuality rate) before the shutdown, and we are an elite unit. Regular units have no problem going 5:1 or 8:1. With Starlink down, 13:1 (casualty rate) for a regular unit is easy,” the unit commander said.
The restrictions come as Russia faces heavy challenges across multiple fronts. A late January report from the Center for Strategic and International Studies estimated that more than 1.2 million Russian troops have been killed, wounded, or gone missing since February 2022.
The Washington-based Institute for the Study of War also noted that activity from Russia’s Rubikon drone unit declined after Feb. 1, suggesting communications constraints from Starlink’s restrictions may be limiting operations. “I’m sure the Russians have (alternative options), but it takes time to maximize their implementation and this (would take) at least four to six months,” Yaroslavsky noted.
Elon Musk
Tesla Korea hiring AI Chip Engineers amid push for high-volume AI chips
Tesla Korea stated that it is seeking “talented individuals to join in developing the world’s highest-level mass-produced AI chips.”
In a recent post on X, Tesla Korea announced that it is hiring AI Chip Design Engineers as part of a project aimed at developing what the company describes as the world’s highest-volume AI chips. CEO Elon Musk later amplified the initiative.
Tesla Korea stated that it is seeking “talented individuals to join in developing the world’s highest-level mass-produced AI chips.”
“This project aims to develop AI chip architecture that will achieve the highest production volume in the world in the future,” Tesla Korea wrote in its post on X.
As per Tesla Korea, those who wish to apply for the AI Chip Design Engineer post should email Ai_Chips@Tesla.com and include “the three most challenging technical problems you have solved.”
Elon Musk echoed the hiring push in a separate post. “If you’re in Korea and want to work on chip design, fabrication or AI software, join Tesla!” he wrote.
The recruitment effort in South Korea comes as Tesla accelerates development of its in-house AI chips, which power its Full Self-Driving (FSD) system, Optimus humanoid robot, and data center training infrastructure.
Tesla has been steadily expanding its silicon development teams globally. In recent months, the company has posted roles in Austin and Palo Alto for silicon module process engineers across lithography, etching, and other chip fabrication disciplines, as noted in a Benzinga report.
Tesla Korea’s hiring efforts align with the company’s long-term goal of designing and producing AI chips at massive scale. Musk has previously stated that Tesla’s future AI chips could become the highest-volume AI processors in the world.
The move also comes amid Tesla’s broader expansion into AI initiatives. The company recently committed about $2 billion into xAI as part of a Series E funding round, reinforcing its focus on artificial intelligence across vehicles, robotics, and compute infrastructure.
Elon Musk
SpaceX and xAI tapped by Pentagon for autonomous drone contest
The six-month competition was launched in January and is said to carry a $100 million award.
SpaceX and its AI subsidiary xAI are reportedly competing in a new Pentagon prize challenge focused on autonomous drone swarming technology, as per a report from Bloomberg News.
The six-month competition was launched in January and is said to carry a $100 million award.
Bloomberg reported that SpaceX and xAI are among a select group invited to participate in the Defense Department’s effort to develop advanced drone swarming capabilities. The goal is reportedly to create systems that can translate voice commands into digital instructions and manage fleets of autonomous drones.
Neither SpaceX, xAI, nor the Pentagon’s Defense Innovation Unit has commented on the report, and Reuters said it could not independently verify the details.
The development follows SpaceX’s recent acquisition of xAI, which pushed the valuation of the combined companies to an impressive $1.25 trillion. The reported competition comes as SpaceX prepares for a potential initial public offering later this year.
The Pentagon has been moving to speed up drone deployment and expand domestic manufacturing capacity, while also seeking tools to counter unauthorized drone activity around airports and major public events. Large-scale gatherings scheduled this year, including the FIFA World Cup and America250 celebrations, have heightened focus on aerial security.
The reported challenge aligns with broader Defense Department investments in artificial intelligence. Last year, OpenAI, Google, Anthropic, and xAI secured Pentagon contracts worth up to $200 million each to advance AI capabilities across defense applications.
Elon Musk previously joined AI and robotics researchers in signing a 2015 open letter calling for a ban on offensive autonomous weapons. In recent years, however, Musk has spoken on X about the strengths of drone technologies in combat situations.
Starlink restrictions are hitting Russian battlefield comms: report
Tesla Korea hiring AI Chip Engineers amid push for high-volume AI chips
