News
SpaceX Starship prototype in limbo after engine test lights rocket on fire
The fate of SpaceX’s fourth full-scale Starship prototype appears to be in limbo after a third (seemingly successful) engine ignition test unintentionally caught the rocket on fire.
Now more than 12 hours after Starship SN4 fired up its new Raptor engine, the ~30m (~100 ft) tall, 9m (~30 ft) wide prototype is apparently trapped with one or both of its propellant tanks still partially filled with liquid (or gaseous) methane and/or oxygen. An initial road closure scheduled from noon to 6pm local quickly came and went and SpaceX and Cameron County Texas have since modified the paperwork, extending the closure a full 24 hours. In other words, SpaceX has reason to believe that Starship SN4 may continue to be unsafe (i.e. pressurized) as many as ~30 hours after it technically completed its third static fire test – extremely unusual, to say the least.
There’s only one obvious conclusion to draw. Whether it was something invisible to the public eye or damage related to the off-nominal fire that burned for some 15 minutes after Raptor shut down, SpaceX appears – to some extent – to have lost control of Starship SN4.
At the moment, it’s unclear what is wrong and what SpaceX is attempting to do to resolve the problem. Based on photos of Starship SN4 taken before the fire, there is good news and bad news from what can be publicly ascertained. Controlled from the ground by unprotected wires strung up and down the rocket and connected at its base, the uncontrolled fire that burned in at least two locations around Starship’s aft may have severed some or all of those critical connections.
That would render Starship – potentially perfectly healthy and operational – almost entirely uncontrollable, while also potentially removing SpaceX’s access to telemetry. In other words, the company may currently have no idea how pressurized all or part of Starship SN4 is and may also have little to no control of some or all of the rocket. For that to be true, Starship SN4 would, however, have to have less than fully redundant control hardware. To perform hops, for example, the ship would need both wired and radio links capable of sending telemetry and receiving commands to remain both on the ground and after liftoff.
It’s possible that Starship SN4 has the necessary hardware installed but that it wasn’t activated for the static fire test (think “Starship will never leave the ground, why would we need to enable wireless controls?”). It’s also possible that the blown pipe and methane leak that appeared to cause the secondary fire damaged crucial propellant management hardware (valves, pumps, etc.) or was just a symptom of an even worse overpressure event that damaged or destroyed multiple such systems.
Given that safety is almost certainly the priority, chances are that some combination of fairly mild hardware failure and telemetry/control loss has left SpaceX with just enough uncertainty that it can’t risk sending technicians to the launch site to inspect the damage and reestablish control. As a result, the only option left is to quite literally sit and wait until it’s once again safe to approach the rocket. Thankfully, at this point, the risk of the mystery problem actually destroying Starship SN4 is very low. If, as it appears, only its methane tank is affected, leaving some unknown quantity of latent liquid methane trapped inside, it’s possible that waiting will actually solve the problem and safe the rocket.
The fact that Starship hasn’t exploded yet strongly implies either that the amount of propellant trapped is minuscule or that the vast majority of SN4’s propellant management systems (including vents) remain functional. Assuming that’s the case, any remaining cryogenic propellant will eventually boil into gas, increasing the pressure inside Starship’s tanks, while those tanks will continue to vent to prevent an explosion or rupture. Eventually, Starship SN4 will be empty once again and SpaceX will be able to approach the rocket to regain control and begin inspections and repairs.
Regardless, after such an unintentionally eventful static fire test, it’s extremely unlikely that SN4 will be ready for its inaugural flight test within the next few days. Stay tuned for updates as SpaceX works to regain control over the fourth full-scale Starship prototype.
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Elon Musk
Tesla’s golden era is no longer a tagline
Tesla “golden era” teaser video highlights the future of transportation and why car ownership itself may be the next thing to change.
The golden age of autonomous ridesharing is arriving, and Tesla is making sure we can all picture a future that looks like the future. A recent teaser posted to X shows a Cybercab parked outside a home, and with a clear message that your everyday life may soon look like this when the driverless vehicles shows up at your door.
Tesla has begun the rollout of its Robotaxi service across US cities, and the production of its dedicated, fully-autonomous Cybercab vehicle. The first Cybercab rolled off the Giga Texas assembly line on February 17, 2026, with volume production now targeted for this month. Additionally, the Robotaxi service built around it is already running, without human drivers, in US cities.
Tesla Cybercab production ignites with 60 units spotted at Giga Texas
The Cybercab is built without a steering wheel, pedals, or side mirrors, designed from the ground up for unsupervised autonomous operation. Musk described the manufacturing approach as closer to consumer electronics than traditional car production, targeting a cycle time of one unit every ten seconds at full scale.
Drone footage from April 13, 2026 captured over 50 Cybercab units on the Giga Texas campus, with several clustered near the crash testing facility. Musk has noted that Tesla plans to sell the Cybercab to consumers for under $30,000, and owners will be able to add their vehicles to the Tesla robotaxi network when not in personal use, potentially generating income to offset the vehicle’s purchase cost. That model changes the math on vehicle ownership in a meaningful way, making a car something closer to a depreciating asset that can also earn by paying itself off and generate a profit.
During Tesla’s Q4 earnings call, the company confirmed plans to expand the Robotaxi program to seven new cities in the first half of 2026, including Dallas, Houston, Phoenix, Miami, Orlando, Tampa, and Las Vegas. The service already runs without safety drivers in Austin, and public road testing of the Cybercab has expanded to five states, including California, Texas, New York, Illinois, and Massachusetts.
Golden era pic.twitter.com/AS6pX2dK8N
— Tesla Robotaxi (@robotaxi) April 16, 2026
News
Tesla’s last chance version of the flagship Model X is officially gone
The Signature Edition was no ordinary Model X Plaid. Offered exclusively by invitation to select existing Tesla owners, it represented the final production batch of the current-generation Model X before manufacturing at Fremont ends.
Tesla enabled a last-chance version of its two flagship vehicles, the Model S and Model X, over the past few weeks. The Model X, the company’s original SUV, is officially gone.
Tesla has officially closed the book on its most exclusive send-off for the Model X. The limited-run Model X Signature Edition—priced at $159,420 before fees and limited to just 100 units—is now sold out, with reservations closed as of April 16.
The $160,000 Model X Signature Edition is officially sold out.
Reservations are now closed. pic.twitter.com/4D5FSkTZTa
— Sawyer Merritt (@SawyerMerritt) April 16, 2026
The Signature Edition was no ordinary Model X Plaid. Offered exclusively by invitation to select existing Tesla owners, it represented the final production batch of the current-generation Model X before manufacturing at Fremont ends.
Every unit featured an exclusive Garnet Red exterior paint, unique badging, and a standard six-seat configuration. With full Plaid powertrain specs—Tri-Motor All-Wheel Drive, over 1,000 horsepower, and blistering acceleration—it was positioned as a collector’s item for loyalists who wanted one last shot at owning a piece of Tesla history.
The timing is no coincidence.
Tesla announced earlier this year that it would discontinue regular production of both the Model S and Model X to repurpose the Fremont factory’s dedicated lines for mass production of its Optimus humanoid robots.
Elon Musk has repeatedly emphasized that Optimus could ultimately become more valuable to the company than its vehicle business, with ambitions to build hundreds of thousands of units annually.
The Signature Editions served as a final “runout” series: 250 for the Model S and only 100 for the Model X, all built to the highest Plaid specification before the line is converted.
Deliveries of the remaining Signature units are scheduled to begin in May 2026. For buyers who secured one, it’s the ultimate swan song for a vehicle that helped define Tesla’s early luxury EV dominance.
Launched in 2015, the Model X introduced falcon-wing doors, a panoramic windshield, and class-leading performance that turned heads and set benchmarks. While newer models like the Cybertruck and refreshed Model Y have taken center stage, the Model X Plaid remained a halo product for those seeking maximum range, space, and speed in an SUV package.
With inventory of standard Model X units already nearly exhausted across the U.S., the rapid sell-out of the Signature Edition underscores enduring demand for Tesla’s premium flagships even as the company pivots toward robotics and autonomy.
For enthusiasts, these 100 garnet-red SUVs will likely become instant collector’s items—tangible reminders of the vehicles that built the brand before Tesla’s next chapter fully begins. The last chance is gone, but the legacy endures.
Elon Musk
Tesla Optimus V3 hand and arm details revealed in new patents
Two new patents, which were coincidentally filed on the same day as the “We, Robot” event back in October 2024, protect Tesla’s mechanically actuated, tendon-driven architecture.
Tesla is planning to soon reveal its latest and greatest version of the Optimus humanoid robot, and a series of new patents for the hands and arms, with the former being, admittedly, one of the most challenging parts of developing the project.
Two new patents, which were coincidentally filed on the same day as the “We, Robot” event back in October 2024, protect Tesla’s mechanically actuated, tendon-driven architecture.
The designs relocate heavy actuators to the forearm, route cables through a sophisticated wrist design, and employ innovative joint assemblies to achieve human-like dexterity while enabling lightweight construction and high-volume manufacturing.
Core Tendon-Driven Hand Architecture
The primary patent, which is titled “Mechanically Actuated Robotic Hand,” details a cable/tendon-driven system.
Actuators are positioned in the forearm rather than the hand. Each finger features four degrees of freedom (DoF), while the wrist adds two more.
Tesla’s Optimus V3 robot hand looks to have been revealed in a new international patent published today.
The patent describes a tendon/cable-driven hand:
• Actuators in the forearm
• Each finger has 4 degrees of freedom
• The wrist has 2 degrees of freedom
• Tendon-driven… pic.twitter.com/eE8xLEYSrx— Sawyer Merritt (@SawyerMerritt) April 16, 2026
Three thin, flexible control cables (tendons) per finger extend from the forearm actuators, pass through the wrist, and connect to the finger segments. Integrated channels within the finger phalanges guide these cables selectively—routing behind some joints and forward of others—to enable independent bending without unintended motion.
Patent diagrams illustrate thick cable bundles emerging from the wrist into the palm and fingers, with labeled pivots and routing guides. This setup closely mirrors human forearm-muscle and tendon anatomy, where most hand control originates proximally.
Advanced Wrist Routing Innovation
One of the standout features is the wrist’s cable transition mechanism. Cables shift from a lateral stack on the forearm side to a vertical stack on the hand side through a specialized transition zone.
Boom! @Tesla_Optimus 의 3세대 구조로 추정되는, 로봇 팔 및 관절에 대한 특허가 공개되었습니다.
아티클 작업에 들어가겠습니다.
1년 넘게 기다려 온, 정말 귀한 특허인데, 조회수 100만대로 터져줬으면 좋겠네요. 😉@herbertong @SawyerMerritt@GoingBallistic5 @TheHumanoidHub pic.twitter.com/CCEiIlMFSX
— SETI Park (@seti_park) April 16, 2026
This geometry significantly reduces cable stretch, torque, friction, and crosstalk during combined yaw and pitch wrist movements — common failure points in simpler tendon systems that cause imprecise or jerky motion.
By minimizing these issues, the design supports smoother, more reliable multi-axis wrist operation, essential for complex real-world tasks.
Companion Patents on Appendage and Joint Design
Two supporting patents provide additional depth. “Robotic Appendage” covers the overall forearm-to-palm-to-finger assembly, with a palm body movably coupled to the forearm and finger phalanges linked by tensile cables returning to forearm actuators. Tensioning these cables repositions the phalanges precisely.
“Joint Assembly for Robotic Appendage” describes curved contact surfaces on mating structures paired with a composite flexible member. This allows smooth pivoting while maintaining consistent tension, enhancing durability, and simplifying assembly for mass production.
Executive Insights on Hand Development Challenges
Tesla executives have consistently described the hand as the most difficult component of Optimus.
Elon Musk has called it “the majority of the engineering difficulty of the entire robot,” emphasizing that human hands possess roughly 27–28 DoF with an intricate tendon network powered largely by forearm muscles. He has likened the challenge to something “harder than Cybertruck or Model X… somewhere between Model X and Starship.”
In mid-2025, Musk acknowledged that Tesla was “struggling” to finalize the hand and forearm design. By early 2026, he stated that the company had overcome the “hardest” problems, including human-level manual dexterity, real-world AI integration, and volume production scalability.
He estimated the electromechanical hand represents about 60 percent of the overall Optimus challenge, compounded by the lack of an existing supply chain for such precision components.
These patents directly tackle the acknowledged pain points: relocating actuators reduces hand mass and inertia for better speed and efficiency; advanced wrist routing and joint geometry address friction and crosstalk; and simplified, stackable parts visible in the diagrams indicate readiness for high-volume manufacturing.
Implications for Optimus Production and Leadership
Collectively, the patents portray the Optimus v3 hand not as a mere prototype, but as a production-oriented system engineered from first principles.
The 22-DoF architecture, forearm-driven tendons, and crosstalk-minimizing wrist deliver a clear competitive edge in dexterity. They align with Musk’s view that high-volume manufacturing is one of the three critical elements missing from most other humanoid projects.
For Optimus to become the most capable humanoid robot, its hand needed to replicate the useful and applicable design of the human counterpart.
These filings demonstrate that Tesla has transformed years of engineering challenges into patented, elegant solutions — positioning the company strongly in the race toward general-purpose robotics.
Tesla’s golden era is no longer a tagline
Tesla’s last chance version of the flagship Model X is officially gone
