Connect with us

News

Ex-SpaceX engine expert to help design rockets built for launch on world’s largest jet

Published

on

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.

Advertisement

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.

Advertisement

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

 

Advertisement

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.

 

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.

Advertisement

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!

Advertisement

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.

Advertisement
Comments

News

Tesla Semi gets strange-but-understandable comparison from Jay Leno

In a recent interview with MotorTrend, legendary comedian and automotive enthusiast Jay Leno shared his impressions after driving Tesla’s long-range Semi truck, offering one of the most vivid descriptions to date:

Published

on

Credit: Jay Leno's Garage

The Tesla Semi recently received a strange-but-understandable comparison from automotive enthusiast and former long-time late-night television show host Jay Leno.

In a recent interview with MotorTrend, legendary comedian and automotive enthusiast Jay Leno shared his impressions after driving Tesla’s long-range Semi truck, offering one of the most vivid descriptions to date:

“It’s like driving an office building.”

The comparison may seem quirky—office buildings evoke images of immobility rather than motion—but it aptly conveys the experience of commanding a massive 23,000-pound Class 8 electric truck that delivers sports-car acceleration.

Advertisement

Lenotested the production-spec Long Range model, which is rated for up to 500 miles of range. He was visibly impressed by its performance, noting how the enormous vehicle moves with surprising urgency.

“It’s as fast as a Tesla, but it’s like driving an office building,” he remarked. “It’s this huge thing that moves like right now. You go 500 miles. You get 60% charge in 30 minutes. You’re saving on fuel costs. It seems quite good.”

The reaction highlights the cognitive dissonance at the core of the Tesla Semi. Traditional diesel semi-trucks are slow, noisy, and expensive to run. The Semi rewrites the rules with instant torque from its tri-motor electric powertrain, producing up to 800 kW.

Despite its size, the truck feels agile thanks to full electric steering assist, upgraded actuators borrowed from the Cybertruck, and a 48-volt electrical architecture that improves responsiveness and efficiency.

Tesla reports real-world energy consumption below 1.7 kWh per mile for the Long Range version. Megacharger stations can deliver a 60% charge in roughly 30 minutes, making the truck suitable for long-haul operations.

Advertisement

Additional features include an electric Power Take-Off (ePTO) capable of 25 kW for trailer refrigeration or other equipment, and a driver-focused cab with a central seating position for optimal visibility and a quiet, high-tech interior.

Fleet operators stand to benefit significantly from the economics. Diesel trucks often cost nearly one dollar per mile when including fuel, maintenance, and downtime.

Tesla projects the Semi can reduce operating costs to as low as 15 cents per mile through cheaper electricity, regenerative braking that minimizes brake wear, and reduced service requirements. While early deployments, like Pepsi’s, focused on shorter routes, the 500-mile variant targets cross-country applications.

Obstacles remain. A fully loaded tractor-trailer can reach 80,000 pounds, which reduces real-world range compared to the unloaded test conditions. Building out a nationwide Megacharger network will be essential for broader adoption. The Semi also carries a higher upfront price than conventional diesels, though total cost of ownership and available incentives frequently tip the scales in its favor over time.

Advertisement

Tesla Semi hauls fresh Cybercab batch as Robotaxi era takes hold

Leno’s “office building” description resonates because it captures the unexpected thrill of piloting something so large yet so capable. As the trucking industry faces pressure to cut emissions and control rising fuel expenses, the Semi offers a compelling alternative that excels in performance, comfort, and efficiency.

Coming from a man who has driven everything from vintage classics to modern hypercars, Leno’s genuine enthusiasm adds weight to the verdict.

The Tesla Semi is emerging as more than an experimental EV—it represents a practical vision for the future of heavy-duty transport where massive rigs accelerate instantly, and the numbers finally make sense. If fleet results continue to validate the claims, the era of diesel dominance could be drawing to a close.

Advertisement
Continue Reading

News

Tesla expands its mass-market color palette in the U.S.

Delivering a fresh splash of color to its lineup, Tesla is giving U.S. buyers two stunning new blue options that are already turning heads.

Published

on

Credit: Brand0n | X

Tesla has expanded the color palette it offers on its mass market vehicles in the United States, giving buyers of the Model 3 and Model Y a few additional options than before.

Delivering a fresh splash of color to its lineup, Tesla is giving U.S. buyers two stunning new blue options that are already turning heads. Starting on May 8, the automaker updated its North American configurator to introduce Marine Blue on Model Y Premium trims and Frost Blue exclusively on the Model 3 Performance.

The move replaces the long-running Deep Blue Metallic, a staple for over eight years, and brings previously exclusive shades stateside.

Marine Blue, a deep, rich oceanic hue formerly limited to Europe and Asia-Pacific markets, is now available on Model 3 and Model Y RWD and Long Range AWD Premium variants. Priced at a $1,000 upgrade—standard for Tesla’s premium paints—it delivers a sophisticated, metallic finish that shifts beautifully under light.

Tesla North America highlighted the change directly in an official post, confirming Marine Blue as the new flagship blue for non-Performance models.

Frost Blue, on the other hand, is the real crowd-pleaser for enthusiasts. Previously reserved for the flagship Model S and Model X, this lighter, icy metallic shade is now offered at no extra cost on Model 3 Performance and Model Y Performance trims.

Advertisement

Performance buyers effectively get a premium color included in the base price, a smart perk that Tesla has extended to higher-end variants across the board. Early in-person sightings and configurator renders show Frost Blue’s cool, modern vibe popping against the cars’ sleek lines, especially with black wheels and red brake calipers.

The timing couldn’t be better. With Tesla pushing refreshed Model 3 and Model Y refreshes amid growing competition, these updates add visual excitement without major redesigns.

Advertisement

Deep Blue Metallic orders are being transitioned to the new shades, according to customer reports and Tesla communications. In the U.S., Puerto Rico, and Mexico, the options are live now; Canada sees limited Frost Blue availability on the Model 3 Performance.

Tesla’s color strategy continues to evolve, borrowing from higher-end models to refresh mass-market EVs. Now that we bid farewell to the Model S and Model X, some of their colors might be available on the more widely available Model 3 and Model Y.

Continue Reading

Elon Musk

Tesla Semi’s official battery capacity leaked by California regulators

A California regulatory filing just confirmed the exact battery size inside each Tesla Semi variant.

Published

on

By

A regulatory filing published by the California Air Resources Board in April 2026 has put official numbers on what Tesla Semi owners and fleet buyers have long wanted confirmed: the exact battery capacities of both the Long Range and Standard Range Semi truck variants. CARB is California’s independent air quality regulator, and it certifies zero-emission powertrains before they can be sold or operated in the state. When a manufacturer submits a vehicle for certification, the resulting executive order becomes a public document, making it one of the most reliable sources for confirmed production specs on any EV.

The document lists two certified powertrain configurations. The Long Range Semi carries a usable battery capacity of 822 kWh, while the Standard Range version comes in at 548 kWh. Both use lithium-ion NCMA chemistry and share the same peak and steady-state motor output ratings of 800 kW and 525 kW respectively. Cross-referencing Tesla’s published efficiency figure of approximately 1.7 kWh per mile under full load, the 822 kWh pack supports roughly 480 miles of real-world range, which aligns closely with Tesla’s advertised 500-mile figure for the Long Range trim. The 548 kWh Standard Range pack works out to approximately 320 miles, again consistent with Tesla’s stated 325-mile target.

Here is a direct comparison of the two versions based on the CARB filing and published specs:

Tesla Semi Spec Long Range Standard Range
Battery Capacity 822 kWh 548 kWh
Battery Chemistry NCMA Li-Ion NCMA Li-Ion
Peak Motor Power 800 kW 525 kW
Estimated Range ~500 miles ~325 miles
Efficiency ~1.7 kWh/mile ~1.7 kWh/mile
Est. Price ~$290,000 ~$260,000
GVW Rating 82,000 lbs 82,000 lbs

The timing of this certification is not incidental. On April 29, 2026, Semi Programme Director Dan Priestley confirmed on X that high-volume production is now ramping at Tesla’s dedicated 1.7-million-square-foot facility in Sparks, Nevada. A key advantage of the Nevada location is vertical integration: the 4680 battery cells powering the Semi are manufactured in the same complex, eliminating the supply chain bottleneck that had delayed the program for years.

Advertisement

Tesla’s long-term goal is to reach a production capacity of 50,000 trucks annually at the Nevada factory, which would represent roughly 20 percent of the entire North American Class 8 market. With CARB certification now in hand and the production line running, the regulatory and manufacturing groundwork for that target is in place.

Continue Reading