News
SpaceX rapidly stacks Starship and Super Heavy with ‘Mechazilla’
For the second time ever, SpaceX has used Starbase’s ‘Mechazilla’ tower and arms to stack a Starship upper stage on top of a Super Heavy booster.
This time around, though, SpaceX clearly learned a great deal from its second February 9th Starship stack and was able to complete the stacking process several times faster on March 15th. During the second attempt, depending on how one measures it, it took SpaceX around three and a half hours from the start of the lift to Starship fully resting on Super Heavy. With Stack #3, however, SpaceX was able to lift, translate, lower, and attach Starship to Super Heavy in just over an hour.
Oddly, SpaceX managed that feat without a claw-like device meant to grab and stabilize Super Heavy during stacking operations. For Stack #2, all three arms were fully in play. First, a pair of ‘chopsticks’ – giant arms meant to grab, lift, and even recover Starships and boosters – grabbed Ship 20, lifted it close to 100 meters (~300 ft) above the ground, rotated it over top of Super Heavy, and briefly paused. A third arm – known as the ship quick-disconnect or umbilical arm – swung in and extended its ‘claw’ to grab onto hardpoints located near the top of Super Heavy. Once the booster was secured, the ‘chopsticks’ slowly lowered Ship 20 onto Booster 4’s interstage and six clamps joined the two stages together.
A few hours after the two were clamped together, an umbilical device located on the swing arm extended and connected to Ship 20. It’s unclear if the panel was actually used in any way but the umbilical is designed to connect Starship to ground systems to supply propellant, power, communications, and other consumables. Regardless, the device did appear to connect to Starship. Prior to Stack #3, however, SpaceX removed both of the swing arm’s ‘claws,’ meaning that it had no way to grab onto Super Heavy. That diminished capability clearly appeared to have zero impact on the ease or speed of the stacking process given that it was completed a full three times faster than Stack #2.
That could imply that the claw is either completely unnecessary or only needed when attempting stacking operations in extreme winds. What is clear is that the claw removal likely only shaved a handful of minutes off of the full stacking process. What really saved time on Stack #3 was a faster lift and fewer pauses throughout – especially while lowering Starship the last several meters onto Super Heavy. During Stack #2, SpaceX took close to an hour and a half to fully lower Ship 20. The same sequence took just ~20 minutes during Stack #3.
Still, after the impressively rapid one-hour stack, it then took SpaceX close to two hours to connect the swing arm’s umbilical to Starship, leaving plenty of room for improvement. Ultimately, assuming SpaceX can speed up the start of the stacking process and replicate its Starship success with Super Heavy, which will also need to be grabbed and installed on an even more complex launch mount, it’s possible that Starbase’s orbital launch integration system is already capable of supporting multiple Starship launches per day. Of course, SpaceX has yet to demonstrate that the orbital launch site can be turned around in a matter of hours after being subjected to the violence and stresses of a Starship launch.
More significantly, SpaceX has never even attempted an orbital Starship launch, recovery, or reuse. That leaves the company in the unusual position of building and testing expensive, specialized support equipment before it actually knows that the rocket that equipment is designed to support is in any way capable of taking advantage of it. For an orbital spacecraft the size of Starship, only the Space Shuttle comes anywhere close and NASA’s all-time record for orbiter turnaround was 54 days. SpaceX has technically flown two Falcon 9 boosters twice in 27 days but no matter how impressive that feat is, reusing a far smaller suborbital booster is vastly easier than reusing a massive orbital spacecraft.
At the end of the day, it’s not really SpaceX’s fault that it’s still waiting for permission to attempt orbital test flights. Nonetheless, the growing gap in maturity between Starship and Super Heavy and the orbital launch site designed to support them continuously raises the risk that SpaceX will have to extensively redesign the rocket, its support equipment, or both if significant problems arise during orbital test flights.
Up next, there’s a chance that SpaceX could attempt to cryoproof Starship while on top of Super Heavy – or perhaps both stages at once. While SpaceX has performed more than half a dozen cryoproofs of Ship 20 and Booster 4 using the orbital launch site’s propellant storage and distribution system, it hasn’t fully tested the hardware needed to route hundreds of tons of propellant hundreds of feet into the air – essential for full-stack testing and launch operations.
Tesla (NASDAQ: TSLA) is set to hold its Earnings Call for the first quarter of 2026 on Wednesday, and there are a lot of interesting things that are swirling around in terms of speculation from investors.
With the company’s executives, including CEO Elon Musk, answering a handful of questions that investors submit through the Say platform, fans want to know a lot of things about a lot of things.
These five questions come from Retail Investors, who are normal, everyday shareholders:
- When will we have the Optimus v3 reveal? When will Optimus production start, since we ended the Model S and Model X production earlier than mid-year? What’s the expected Optimus production rate exiting this year? What are the initial targeted skills?
- What milestones are you targeting for unsupervised FSD and Robotaxi expansion beyond Austin this year, and how will that drive recurring revenue?
- How will Hardware 3 cars reach Unsupervised Full Self-Driving?
- When do you expect Unsupervised Full Self-Driving to reach customer cars?
- When will Robotaxi expand past its current limited rollout?
Additionally, these are currently the three questions that are slated to be answered by Institutional Firms, which also answer a handful of questions during the call:
- Now that FSD has been approved in the Netherlands and is expected to launch across Europe this summer, can you discuss your Robotaxi strategy for the region?
- What enabled you to finish the AI5 tapeout early and were there any changes to the original vision? Last week, Elon said AI5 will go into Optimus and the Supercomputer, but one month ago said it would go into the Robotaxi. Has AI5 been dropped from the vehicle roadmap?
- Given the recent NHTSA incident filings, can you update us on the Robotaxi safety data? If safety validation remains the primary bottleneck, why not deploy thousands of vehicles to accelerate the removal of the safety driver?
The questions range through every current Tesla project, including FSD expansion and Optimus. However, many of the answers we will get will likely be repetitive answers we’ve heard in the past.
This is especially pertinent when the questions about when Unsupervised FSD will reach customer cars: we know Musk will say that it will happen this year. Is Tesla capable of that? Maybe. But a more transparent answer that is more revealing of a true timeline would be appreciated.
Hardware 3 owners are anxiously awaiting the arrival of FSD v14 Lite, which was promised to them last year for a release sometime this year.
The Earnings Call is set to take place on Wednesday at market close.
Elon Musk
Elon Musk reveals shocking Tesla Optimus patent detail
What looked promising on paper and in simulations failed to deliver the reliability required for a robot expected to handle delicate tasks like folding laundry, assembling electronics, or assisting in factories and homes.
Elon Musk revealed a shocking detail on the Tesla Optimus patent that was revealed last week. Despite it being made public for the first time, Musk said the company has already moved on from the design, an incredible truth about the development of new technology: things move fast.
Musk dropped a bombshell about the Tesla Optimus humanoid robot hand patent that was released last week. Musk, candidly replying to a post late at night on X, revealed that what is a new technology to many fans and insiders is actually old news to those developing the tech directly.
“We already changed the design,” Musk said. “This one didn’t actually work.”
We already changed the design. This one didn’t actually work.
— Elon Musk (@elonmusk) April 19, 2026
Patents, after all, are often viewed as blueprints for future products. Yet Musk revealed that the rolling contact mechanism—intended to provide smooth, low-friction articulation in the fingers—had already been scrapped after real-world testing exposed its shortcomings.
What looked promising on paper and in simulations failed to deliver the reliability required for a robot expected to handle delicate tasks like folding laundry, assembling electronics, or assisting in factories and homes.
The hand has been one of the biggest challenges for Tesla engineers since Optimus development started years ago. Musk has said that there is not enough recognition for how incredible and useful the human hand is, and designing one for a humanoid robot has been the biggest challenge of all.
Tesla is stumped on how to engineer this Optimus part, but they’re close
This moment underscores the persistent engineering hurdles in achieving reliable humanoid hand dexterity. Human fingers are marvels of evolution: 27 bones, intricate tendons, ligaments, and a network of sensors working in perfect harmony. Replicating that in metal and silicon is extraordinarily difficult.
Rolling contacts promised reduced wear and precise motion, but testing likely revealed issues with durability under repeated stress, grip stability on varied surfaces, or the micro-precision needed for fine motor skills.
These aren’t minor tweaks, but instead they represent fundamental challenges that have plagued robotics teams for decades. Even advanced competitors struggle here—hands remain the Achilles’ heel of most humanoids because the margin for error is razor-thin.
A fraction of a millimeter off, and a robot drops a glass or fails to button a shirt.
What makes Musk’s reply remarkable is how it signals Tesla’s direct communication style on prototype limitations. While many companies guard failures behind glossy marketing and vague timelines, Tesla openly shares setbacks.
Musk was forthcoming about the failure of this recent design. This transparency builds trust with investors, engineers, and fans. It shows Tesla treats Optimus development like true science: rapid iteration, rigorous testing, and zero tolerance for hype that doesn’t match reality.
The disclosure from Musk also highlights Tesla’s blistering pace of development. By the time the patents are published, which is often over a year after the initial filing, the technology has already evolved.
Optimus is far from a static product, and it’s a living project advancing weekly.
In the high-stakes race for general-purpose robots, Tesla’s approach stands out. Admitting a finger-joint design “didn’t actually work” isn’t a weakness—it’s confidence.
True innovation demands confronting failure head-on, and Musk just reminded the world that Optimus is being engineered that way. The next version of those hands is already in testing, and it will be better because Tesla isn’t afraid to say what didn’t work.
Elon Musk
Tesla is sending its humanoid Optimus robot to the Boston Marathon
Tesla’s Optimus robot is heading to the Boston Marathon finish line
Tesla’s Optimus humanoid robot will be stationed at the Tesla showroom at 888 Boylston Street in Boston, right along the final stretch of the Boston Marathon today, ready to cheer on runners and pose for photos with spectators.
According to a Tesla email shared by content creator Sawyer Merritt on X, Optimus will be at the Boston Boylston Street showroom on April 20, coinciding with Marathon Monday weekend. The Boston Marathon finishes on Boylston Street, and the surrounding area draws hundreds of thousands of spectators along with international broadcast coverage. Placing Optimus there puts it in front of a massive public audience at zero advertising cost.
Just got this email. @Tesla’s Optimus robot is coming to Boston.
“Join us from April 19 to 20, 2026, at Tesla Boston Boylston Street showroom to meet Optimus, our humanoid robot, for Marathon Monday. Optimus will be cheering with you on the sidelines and posing for photos.” pic.twitter.com/chxoooO2xV
— Sawyer Merritt (@SawyerMerritt) April 18, 2026
The Tesla showroom is at 888 Boylston Street, between Gloucester Street and Fairfield Street. The final mile of the marathon runs directly along Boylston Street, with runners passing the big stores before reaching the finish line at Copley Square.
Optimus was first announced at Tesla’s AI Day event on August 19, 2021, when Elon Musk presented a vision for a general-purpose robot designed to take on dangerous, repetitive, and unwanted tasks. In March 2026, Optimus appeared at the Appliance and Electronics World Expo in Shanghai, where on-site staff stated that mass production of the robot could begin by the end of 2026. Before that, it showed up at the Tesla Hollywood Diner opening in July 2025 and at a Miami showroom event in December 2025.
Tesla’s well-calculated display of Optimus gives the public a low-pressure first encounter with a robot that Tesla is preparing to soon deploy at scale. The company has previously indicated plans to manufacture Optimus robots at its Fremont facility at up to 1 million units annually, with an Optimus production line at Gigafactory Texas targeting 10 million units per year.
Tesla showcases Optimus humanoid robot at AWE 2026 in Shanghai
Musk has said that Optimus “has the potential to be more significant than the vehicle business over time,” and separately that roughly 80 percent of Tesla’s future value will come from the robot program. Whether that holds depends on production execution. For now, Boston gets a preview of what that future looks like, standing at the finish line on Boylston Street while 32,000 runners pass by.
Tesla Q1 Earnings: What Elon Musk and Co. will answer during the call
Elon Musk reveals shocking Tesla Optimus patent detail
