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Ex-SpaceX engine expert to help design rockets built for launch on world’s largest jet
Stratolaunch, an aerospace company funded by Microsoft-made billionaire Paul Allen to build the world’s largest flightworthy aircraft, has announced a decision to build its own liquid-fueled rockets, to be air-launched from the aforementioned mega-plane.
Targeting an inaugural launch of the first version of the rocket – currently nicknamed “Kraken” – as early as 2022, Stratolaunch has chosen Jeff Thornburg, formerly SpaceX’s Vice President of Propulsion Engineering and the father of the company’s Mars-focused Raptor engine, to lead its foray into in-house rocket propulsion development and manufacturing.
Stratolaunch has confirmed what most people have long speculated: it’s developing its own launch vehicles for its air-launch system, including a reusable space plane that could eventually carry people. pic.twitter.com/nF9lKVe4xk
— Jeff Foust (@jeff_foust) August 20, 2018
But first: building the world’s largest aircraft
Stratolaunch’s first task at hand, however, is to begin flight-testing the largest (hopefully) operational aircraft in history, a prerequisite for the company’s longer-term orbital rocket and spaceplane aspirations. Nicknamed “Roc” after a mythical (and fictional) bird so large it could carry an elephant, the plane certainly lives up to its namesake. Featuring a full six of the same engines that power Boeing’s once-record-breaking 747 airliner and a wingspan that could easily fit three smaller 737 airliners with room to spare, it is genuinely difficult (if not impossible) to successfully convey the sheer scale of Roc outside of witnessing it in person.
Stationed in California’s Mojave Desert, the aircraft’s one and only copy is, for the most part, completed and has spent the brunt of 2018 conducting runway taxi tests, hopefully culminating in an inaugural flight test later this year or early next year. Designed to lift orbital-class rockets weighing as much as 250 metric tons (550,000 lb) to an altitude of at least 9100 meters (30,000 feet), the primary benefit of using aircraft as launch platforms derives from the simple fact that the atmospheric density at 30,000 feet is more than three times less than that at sea level. Similar to aircraft, rocket performance dramatically improves as atmospheric density decreases: less atmosphere means lower drag and pressure.
Rockets that launch from sea-level have to grapple with the difficulties of Earth’s relatively thick atmosphere at that height, with major launch events like “Max-Q” being big concerns almost solely because the dense air exerts major forces on launch vehicles and demands extreme measures like throttling down booster engines (very inefficient) and optimizing structures for aerodynamic efficiency despite the fact that rockets spend very little time operating in a significant atmosphere.
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A launch pad without a rocket (sort of)
However, the simple fact of the matter is that billionaire Paul Allen’s colossal aircraft essentially does not have a single air-launched rocket in the world that can properly take advantage of its capabilities. Originally sized and designed with an air-launched version of SpaceX’s Falcon 9 in mind, that relationship folded amicably after roughly a year (2012), at which point SpaceX realized it would need to almost completely redesign a unique variant of Falcon 9. Your author will readily admit that they have admired the insanity of such a massive plane while still severely doubting its practical utility.
Thankfully, it appears that Allen is adamantly opposed to the idea that Stratolaunch is some silly whim to build the world’s largest plane. Rather, he is exceptionally reserved and pragmatic when discussing the aerial launch platform, according to a recent and extensive interview by Wired Magazine’s Steven Levy.
“Allen isn’t one to show exuberance, and when he speaks about the plane he focuses on its future utility. ‘When you see that giant plane, it’s a little nutty,’ he says. ‘And you don’t build it unless you’re very serious, not only about wanting to see the plane fly but to see it fulfill its purpose. Which is getting vehicles in orbit.’ – Paul Allen, 2018
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- Stratolaunch’s Roc shown with a triplet of Orbital ATK Pegasus XL rockets. (Vulcan Space)
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- Back in 2012, SpaceX briefly entertained the idea of a Falcon 9 variant optimized for air-launch, potentially including crew rating the rocket down the road. (Stratolaunch/Dynetics)
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- The Roc is inconceivably vast. (Stratolaunch)
Currently, Orbital ATK’s (now Northrop Grumman Innovation Systems) air-launched Pegasus XL rocket is the only “customer” in the world that can realistically use Stratolaunch as a launch platform, not exactly an impressive or sustainable launch vehicle with a maximum performance of less than 450 kg (~1000 lbs) to low Earth orbit for an incredible ~$40 million per (expendable) flight.
To answer that call and ensure Stratolaunch’s utility, the company reportedly began seriously considering its own in-house expendable and reusable rockets and propulsion systems sometime in 2016, plans that have since grown concrete and been publicly embedded into Stratolaunch’s overarching mission. Nicknamed “Kraken” after the mythical sea monster, the company hopes to develop an initially expendable rocket system capable of launching 3400 – 6000 kg (~7500 – 13250 lbs) into low Earth orbit with single booster and triple booster variants. Further down the line, Stratolaunch is eyeing the design and production of a fully and rapidly reusable orbital spaceplane, potentially including a version that would carry astronauts into space.
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- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
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- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
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- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
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- SpaceX’s subscale Raptor engine has completed more than 1200 seconds of testing in less than two years. (SpaceX)
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- BFS (circa 2017) shows off its complement of SL and Vacuum Raptor engines. SpaceX is moving back to something similar to this. (SpaceX)
Normally, one might simply roll their eyes at yet another startup touting small(ish) expendable rockets with first launches no earlier than the early 2020s – the market is getting to be absurdly and impossibly overcrowded at this point. However, Stratolaunch differs for one fundamental and reason: they have placed ex-SpaceX propulsion executive and expert Jeff Thornburg at the helm of the company’s freshly public rocket propulsion wing. While at SpaceX, Mr. Thornburg spent all but one of his five years with the company (2011-2015) single-mindedly focused on the development and engineering of all aspects of the Raptor rocket engine, a next-generation propulsion system designed to enable SpaceX’s sustainable colonization of Mars.
Raptor is an exceptional rocket engine thanks in no small part to Thornburg’s brilliance as a propulsion engineer, and that same brilliance and half-decade of experience at the most successful rocket startup in existence could ultimately prove a massive boon for Stratolaunch’s otherwise interesting but unexceptional expendable rocket concepts.
Put simply, under Jeff Thornburg’s direction and with access to founder Paul Allen’s considerable wealth, Stratolaunch is undoubtedly worth keeping a close eye in the future, both far and near.
For prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket recovery fleet check out our brand new LaunchPad and LandingZone newsletters!
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Tesla finally got its Nevada Robotaxi Permit but with a few catches hard to miss
Nevada granted Tesla’s robotaxi permit, but capped the fleet at just ten vehicles for now.
Tesla has received its robotaxi permit in Nevada, more than two months after regulators closed the public comment period on the company’s application. News of the approval surfaced Wednesday night when Tesla investor and longtime company watcher Sawyer Merritt posted a copy of the interim order, and the Nevada Transportation Authority’s own carrier registry now lists the permit, AVNC Permit 002 under Docket 26-05015, as active for Tesla Robotaxi, LLC.
Tesla asked Nevada in June for authority to run up to 5,000 vehicles in Clark County within a year, however the permit the NTA issued is initially capping Tesla at ten fully autonomous vehicles and confines them to a defined geofence along the Las Vegas Strip corridor. Any expansion of that operating area, or any increase to the fleet size, requires the NTA’s approval first.
Tesla has received its Autonomous Vehicle Network Company permit in Nevada.
The Nevada Transportation Authority says that operations are limited to a maximum fleet of 10 fully autonomous vehicles and shall be conducted only within the Authority-approved Operational Design… https://t.co/Cxfd6GIfDk pic.twitter.com/iOO6wSZkHF
— Sawyer Merritt (@SawyerMerritt) August 13, 2026
The order also sets rules that look more restrictive than what Tesla runs in Austin. Rides are barred on roads with posted speed limits above 45 miles per hour, pickups are off limits within a quarter mile of Harry Reid International Airport without separate authorization, and every vehicle has to carry visible “Robotaxi” markings while notifying riders before each trip that no one is driving. The order also requires “appropriate human supervision”, language that suggests Nevada isn’t ready to let Tesla offer the rides without a safety monitor that it has run in parts of Austin since January. As with standard protocol with robotaxi services, Tesla must report any accident, system failure, or vehicle that becomes stranded on a Nevada road within five business days.
Tesla is entering a market Nevada already knows well. Zoox, the Amazon owned robotaxi company, has run its own autonomous vehicle permit in the state since last year, building up to roughly 100 vehicles and 350,000 rides along the Strip. That history likely explains why the NTA started Tesla at ten cars rather than the fleet size the company asked for. The agency has a template for scaling a permit up once a company proves out its safety record.
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Tesla’s Nevada application first surfaced in June, when the company filed for the permit alongside plans for a maintenance hub in southwest Las Vegas. The company has said it won’t meaningfully scale its robotaxi fleet anywhere until FSD v15 ships, expected in late 2026 or early 2027, which makes the ten vehicle cap less of a constraint today than it might look on paper. For now, Tesla has the legal right to start Nevada rides. Whether it starts before FSD v15 arrives is a separate question the permit doesn’t answer.
Tesla Energy has introduced the Powerwall Lease in conjunction with Tesla Electric, making the service available in Texas. This new option delivers whole-home backup power using two Powerwall units for a net monthly cost of $35 after credits, accompanied by a low fixed electricity rate.
Under the lease terms, customers pay a one-time order fee of $100. The base lease payment for the two Powerwalls is approximately $122 per month during the first year, subject to a 3 percent annual escalator thereafter. Enrollment in a qualifying Tesla Electric Backup plan or Virtual Power Plant plan provides an $87 monthly credit.
Powerwall Lease is now available with Tesla Electric in Texas
Whole-home backup for $35/month, with a low fixed electricity rate
– Two Powerwalls, $0 installation
– Storm Watch outage protection
– One app to manage it all pic.twitter.com/oTzqc6K3aF— Tesla Energy (@teslaenergy) August 13, 2026
This credit lowers the effective cost to roughly $35 per month plus applicable tax.
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Installation of the standard system carries no additional charge. The package features Storm Watch for outage protection and allows complete management through a single Tesla application. The system supplies continuous whole-home backup capability.
The Powerwall system enables households to maintain electricity during severe storms that disrupt the utility grid. When outages occur, the batteries automatically provide seamless backup power to the home.
Tesla announces 100k Powerwalls are participating in Virtual Power Plants
Tesla Storm Watch monitors weather forecasts and ensures the units are fully charged ahead of anticipated severe weather events so that power remains available throughout the disruption, keeping lights, refrigeration, and other essential systems operating without interruption.
Availability is restricted to select Texas locations where retail electric choice exists. Participants must lease exactly two Powerwall units and maintain continuous enrollment with Tesla Electric. Solar panels cannot be included under this particular lease arrangement.
The monthly credit activates automatically once the system is installed, receives permission to operate, and enrollment is confirmed. To retain the credit, customers are required to stay enrolled in Tesla Electric and fulfill all program conditions.
Nonstandard installations that involve electrical upgrades or special permitting may lead to extra expenses and might impact eligibility for the credit, so be sure to check with either your installer or Tesla to ensure you will still qualify.
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Elon Musk continues to tease the unveiling event for the Tesla Roadster, a continuing trend that has grown into a bigger game of “When” for fans who have been waiting years for the car to finally enter production.
A video shared on X of the Joe Rogan Experience podcast that Musk appeared on last year, teasing the Roadster unveiling, was shared once again on the social media platform. The poster said the Roadster event will be “unforgettable.”
Musk agreed:
Yes
— Elon Musk (@elonmusk) August 12, 2026
The timing is interesting because just yesterday, Musk said that we will be getting flying cars, and for years, Tesla has hinted that it could develop a SpaceX cold gas thruster package that would help the car float or fly for a short period of time.
It would be reasonable to assume Tesla’s major delays with this unveiling event are likely caused by the company’s need to break the rules and push the envelope on nearly everything. Last July, Lars Moravy, Tesla’s VP of Vehicle Engineering, said:
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“Roadster is definitely in development. We did talk about it last Sunday night. We are gearing up for a super cool demo. It’s going to be mind blowing. We showed Elon some cool demos last week of the tech we’ve been working on and he got a little excited.”
The latest updates that Tesla has given us are that the Roadster is in design development, and it did have several potential dates for an unveiling event this year, including April. It was then pushed to August.
However, there are no clues as to when Tesla will be ready, and fans are certainly getting frustrated with the delays.
For what it is worth, Franz von Holzhausen told Jay Leno this week that the event would be “very soon.”
We sure hope.
Tesla finally got its Nevada Robotaxi Permit but with a few catches hard to miss
Tesla launches Powerwall Lease for affordable home backup
