News
Ex-SpaceX engineer leads Stratolaunch to major rocket engine test milestone
Led by rocket propulsion expert Jeff Thornburg, Stratolaunch – famous for owning the largest fixed-wing aircraft ever built – has completed the first hot-fire test of a full-scale rocket engine component known as the preburner, a major milestone in the development of any launch vehicle or propulsion system.
Despite the significant size and power of the component, destined to support an engine that will generate 200,000 pounds (~900 kN) of thrust, Thornburg and his team of engineers and technicians have managed to go from designing the preburner to successfully hot-firing a full-scale test article, an extraordinary achievement by any measure.
The team made amazing progress this week! Check out the #PGAEngine preburner’s first hot-fire test at @NASAStennis. #NewUSEngine pic.twitter.com/kKTnf0bj1S
— Stratolaunch (@Stratolaunch) November 6, 2018
Aside from SpaceX, Blue Origin, and Aerojet-Rocketdyne, Stratolaunch is the only private entity developing – let alone testing full-scale parts for – a liquid-fueled rocket engine as large as PGA. Shorthand for the Stratolaunch’s late founder and bankroller Paul G. Allen, PGA is a fuel-rich staged combustion cycle engine that uses liquid hydrogen and oxygen (hydrolox) fuel and oxidizer, typically resulting in high efficiency. In terms of scale and thrust, PGA is very closely comparable to SpaceX’s Merlin 1D engine, which uses kerosene instead of hydrogen but produces roughly 190,000 lbf (850 kN) of thrust and stands 4 feet (1.2m) wide and ~10 feet (~3m) tall.
Another major difference between PGA and Merlin 1D is the fact Merlin 1D’s nozzle is largely optimized for sea level while PGA is being built for a rocket that will be “launched” from a massive plane flying around 35,000 feet (~10.5 km), ultimately resulting in a nozzle that is much wider and longer, featuring nearly the same proportions as fully vacuum-optimized engines like SpaceX’s MVac. By widening the nozzle relative to the rest of the engine, rocket engines are able to operate far more efficiently at higher altitudes, where Earth’s atmosphere thins and exerts less pressure on the escaping exhaust gases. This is visualized well by the visible expansion of rocket exhausts during launches, morphing from a straight cylinder to a massive teardrop-shaped plume. At lower altitudes (and thus higher atmospheric pressures), wider nozzles can produce extreme turbulence and will ultimately shake themselves to destruction, preventing their usage on ground-launched rocket boosters.
Judging from official renders of the engine, PGA’s in-atmosphere variant appears to utilize a form of regenerative nozzle cooling very similar to that used on M1D, where liquid propellant flows through thin capillaries sandwiched between two or more layers of metal to cool the nozzle much like cold water chills the skin of an uninsulated water bottle.
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- A to-scale comparison of Falcon 1, Pegasus XL, MLV, and Falcon 9. (Teslarati/Stratolaunch/Wikipedia)
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- A render of Stratolaunch’s impressive PGA engine. Note the giant nozzle relative to the throat. (Stratolaunch)
Testing rocket engine preburners
In the case of staged combustion cycle hydrolox rocket engines, a small portion of liquid oxygen and all of the liquid hydrogen (hence “fuel-rich”) are mixed and combusted to generate hot gas that then spools up the engine’s primary turbopump(s), ultimately drawing fuel and oxidizer into the combustion quickly enough to ignite the engine and generate sustained thrust. The components that get those main turbopumps started are known collectively as the preburner, which is what Stratolaunch successfully tested – at full-scale – for the first time ever last week. For any liquid rocket engine that cannot solely rely on propellant tank pressure to deliver fuel to the combustion chamber, full-scale tests of preburners or gas-generators effectively mark the moment that engines truly become real.
“This is the first step in proving the performance and highly efficient design of the PGA engine. The hot-fire test is an incredible milestone for both the propulsion team and Stratolaunch.” – Jeff Thornburg, VP of Propulsion, Stratolaunch
Stratolaunch’s propulsion team will continue to test the preburner for longer durations and at higher power levels over the next several months, likely optimizing operations and tweaking or upgrading the preburner’s hardware as real tests produce valuable lessons-learned. Built entirely with additive manufacturing (3D printing), the team should be able to rapidly iterate on the physical design of the engine, a rarity in a field where traditional fabrication methods can take weeks or months to produce complex turbomachinery components with mercilessly strict tolerances.
According to Thornburg, the ultimate goal is to continue that additive-manufacturing-only strategy throughout the development of this rocket engine, theoretically enabling unprecedented design flexibility while also slashing production time throughout. PGA will ultimately power the creatively-named Medium Launch Vehicle (MLV), a small-ish air-launched rocket designed to place a respectable 3400 kg into low Earth orbit (LEO) as early as 2022, as well as a Heavy version of MLV and, potentially, a reusable spaceplane somewhere down the line.
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- PGA’s first full-scale preburner seen during assembly. (Stratolaunch)
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- PGA’s first full-scale preburner seen during assembly. (Stratolaunch)
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- Jeff Thornburg stands in front of Stratolaunch’s NASA Stennis Space Center test stand. (Stratolaunch)
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- The PGA preburner seen after installation at Stennis. (Stratolaunch)
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- The control center. (Stratolaunch)
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- MLV is released from Stratolauncher. (Stratolaunch)
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- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
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Elon Musk
Tesla is ramping up its advertising strategy on social media
Tesla has long stood out in the automotive world for its unconventional approach to advertising—or, more accurately, its near-total avoidance of it. For over a decade, the company spent virtually nothing on traditional marketing.
Tesla seems to be ramping up its advertising strategy on social media once again. Marketing and advertising have not been a major focus of Tesla’s, something that has brought some criticism to the company from its fans.
However, the company looks to be making adjustments to that narrative, as it has at times in the past, as ads were spotted on several different platforms over the past few days.
On Facebook and YouTube, ads were spotted that were evidently placed by Tesla. On Facebook, Tesla was advertising Full Self-Driving, and on YouTube, an ad for its Energy Division was spotted:
Tesla also threw up some ads on YouTube for Energy https://t.co/19DGQMjBsA pic.twitter.com/XQRfgaDKxY
— TESLARATI (@Teslarati) March 9, 2026
Tesla has long stood out in the automotive world for its unconventional approach to advertising—or, more accurately, its near-total avoidance of it. For over a decade, the company spent virtually nothing on traditional marketing.
In 2022, Tesla’s U.S. ad spend was roughly $152,000, a rounding error compared to General Motors’ $3.6 billion the following year.
Traditional automakers averaged about $495 per vehicle on ads; Tesla spent $0. CEOElon Musk’s stance was explicit: “Tesla does not advertise or pay for endorsements,” he posted on X in 2019. “Instead, we use that money to make the product great.”
The strategy relied on word-of-mouth from delighted owners, Elon’s massive X following, viral product launches, media frenzy, and customer referrals. A great product, Musk argued, sells itself. It does not need Super Bowl spots or billboards. Resources poured into R&D instead, with Tesla investing nearly $3,000 per car, far more than rivals.
Tesla counters jab at lack of advertising with perfect response
This reluctance wasn’t arrogance; it was philosophy, and Musk made it clear that the money was better spent on the product. Heavy spending on ads was seen as wasteful when innovation and authenticity drove organic demand. Shareholder calls for marketing budgets were ignored.
The current shift, paid Facebook ads promoting Full Self-Driving (Supervised) and YouTube Shorts offering up to $1,000 back on Powerwall batteries, marks a pragmatic evolution.
These targeted campaigns coincide with the end of one-time FSD purchases and a March 31 deadline for FSD transfer eligibility on new vehicles.
This move likely signals Tesla adapting to scale, as well as a more concerted effort to stop misinformation regarding its platform. As EV competition intensifies and the company bets big on robotaxis and energy storage, pure organic buzz may not suffice to hit adoption targets. Selective digital ads allow precise, cost-effective reach without abandoning core principles.
If successful, it could foreshadow measured expansion into marketing, boosting high-margin software and home energy revenue while preserving Tesla’s innovative edge. But, it’s nice to see the strategy return, especially as Tesla has been reluctant to change its mind in the past.
News
Tesla Model Y outsells everything in three states, but Ford dominates
The Model Y’s success here highlights accelerating mainstream adoption of electric SUVs, which offer spacious interiors, impressive range, rapid acceleration, and low operating costs.
The Tesla Model Y was the best-selling vehicle in three different states in the U.S. last year, according to new data that shows the all-electric crossover outsold every other car in a few places. However, Ford widely dominated the sales figures with its popular F-Series of pickups.
According to new vehicle registration data compiled by Edmunds and visualized by Visual Capitalist, the Ford F-Series, encompassing models like the F-150, F-250, F-350, and F-450, claimed the title of best-selling vehicle in 29 states.
This dominance underscores the pickup truck’s unbreakable appeal across much of the country, particularly in rural, Midwestern, Southern, and Western states, where towing capacity, durability, and utility for work or recreation remain top priorities.
The Tesla Model Y is the best-selling vehicle in California, Washington, and Nevada
How many states will it dominate next year? https://t.co/ERyoyce42D
— TESLARATI (@Teslarati) March 9, 2026
The F-Series has held the crown as America’s overall best-selling vehicle for decades, a streak that continued strong into 2025 despite broader market shifts.
Yet, amid this truck-heavy reality, Tesla made a notable breakthrough. The Model Y emerged as the top-selling vehicle, not just the leading EV, but the outright best-seller in three key states: California, Nevada, and Washington.
These West Coast strongholds reflect regions with robust EV infrastructure, high environmental awareness, generous incentives, and tech-savvy populations. In California alone, nearly 50 percent of new vehicle registrations were electrified, far outpacing the national average of around 25 percent.
The Model Y’s success here highlights accelerating mainstream adoption of electric SUVs, which offer spacious interiors, impressive range, rapid acceleration, and low operating costs.
Elon Musk: Tesla Model Y is world’s best-selling car for 3rd year in a row
Elsewhere, Japanese crossovers filled many gaps: Toyota’s RAV4 and Honda’s CR-V topped charts in several urban and densely populated Northeastern and Midwestern states, where fuel efficiency, reliability, and family-friendly features win out over larger trucks.
While Ford’s broad reach shows traditional preferences persist, at least for now, Tesla’s Model Y victories in high-population, influential states signal a gradual but undeniable transition toward electrification. As charging networks expand and battery technology improves, more states could follow the West Coast’s lead in the coming years.
This 2025 map captures a pivotal moment: pickup trucks still rule the majority, but EVs are carving out meaningful territory where consumer priorities align with sustainability and innovation. The road ahead promises continued competition between legacy giants and electric disruptors.
Elon Musk
Elon Musk shares updated Starship V3 maiden launch target date
The comment was posted on Musk’s official account on social media platform X.
SpaceX CEO Elon Musk shared a brief Starship V3 update in a post on social media platform X, stating the next launch attempt of the spacecraft could take place in about four weeks.
The comment was posted on Musk’s official account on social media platform X.
Musk’s update suggests that Starship Flight 12 could target a launch around early April, though the schedule will depend on several remaining milestones at SpaceX’s Starbase launch facility in Texas.
Among the key steps is testing and certification of the site’s new launch tower, launch mount, and tank farm systems. These upgrades will support the next generation of Starship vehicles.
Booster 19 is expected to roll to the launch site and be placed on the launch mount before returning to the production facility to receive its 33 Raptor engines. The booster would then return for a static fire test, which could mark the first time a Super Heavy booster equipped with Raptor V3 engines is fired on the pad.
Ship 39 is expected to undergo a similar preparation process. The vehicle will likely return to the production site to receive its six engines before heading to Massey’s test site for static fire testing.
Once both stages are prepared, the booster and ship will roll out to the launch site for the first full stack of a V3 Super Heavy and V3 Starship. A full wet dress rehearsal is expected to follow before any launch attempt.
Elon Musk has previously shared how SpaceX plans to eventually recover Starship’s upper stage using the launch tower’s robotic arms. Musk noted that the company will only attempt to catch the Starship spacecraft after two successful soft landings in the ocean. The approach is intended to reduce risk before attempting a recovery over land.
“Should note that SpaceX will only try to catch the ship with the tower after two perfect soft landings in the ocean. The risk of the ship breaking up over land needs to be very low,” Musk wrote in a post on X.
Such a milestone would represent a major step toward the full reuse of the Starship system, which remains a central goal for SpaceX’s long-term launch strategy.
Tesla is ramping up its advertising strategy on social media
Tesla Model Y outsells everything in three states, but Ford dominates
