Key Moments
Bringing Supersonic Flight To The People
Y CombinatorKey Moments
Boom's pivot to building gas turbines after Rolls-Royce's exit wasn't just a survival tactic; it unlocked a massive, unexpected revenue stream funding their supersonic jet development.
Key Insights
When Rolls-Royce withdrew as Boom's engine supplier, Blake Scholl admitted it was one of the worst business decisions he ever made, comparing it to Elon Musk outsourcing SpaceX's engines to a traditional rocket company.
Boom's supersonic jet prototype, the XB-1, achieved supersonic flight without a sonic boom, a feat realized by refining their own engine, which was previously not possible with the proposed Rolls-Royce engine.
The unexpected market for Boom's gas turbines emerged from the AI boom's demand for massive amounts of power, with Sam Altman immediately expressing interest in their 40-megawatt units.
Boom's gas turbine is essentially a modified version of their supersonic jet engine, where the front fan is replaced by an additional turbine connected to an electric generator, producing 42 megawatts.
The US aerospace and defense industry has stagnated, with Boeing not designing a new aircraft since 2004, and major turbine manufacturers using modified jet engines from the 1970s, indicating a lack of innovation.
Boom's business model, by developing its own engines and turbines, allows for rapid adaptation to wartime production needs, with a goal of transitioning from design to a manufactured turbine component in under 24 hours.
The Rolls-Royce engine departure and its strategic impact
Boom's initial strategy to adapt an engine from a major manufacturer like Rolls-Royce for their supersonic jet was a significant misstep, as acknowledged by CEO Blake Scholl. He described it as a "stupid" decision, drawing parallels to SpaceX outsourcing its engine development. The expectation was that leveraging an existing, albeit adapted, engine would be simpler than developing a new one. However, this reliance proved fragile. The situation culminated in early 2022 when Rolls-Royce, facing internal leadership changes, abruptly terminated their agreement. This abrupt exit left Boom without an engine supplier, seemingly jeopardizing the entire project and its funding. The public announcement of this separation by Rolls-Royce was a dramatic blow, causing significant backlash and making it difficult for Boom to secure further investment or partnerships.
Developing Boom's proprietary engine and its technical breakthroughs
Following the Rolls-Royce withdrawal, Boom shifted to developing its own engine. This monumental task involved assembling a skilled engineering team, including former Pratt & Whitney engineers. This in-house development led to a critical breakthrough: achieving supersonic flight without a sonic boom. The team discovered that by optimizing the engine and aircraft design in tandem, they could mitigate the sonic boom effect, a feat that would have been impossible with the original Rolls-Royce engine proposal. This was not a minor adjustment; their own engine allowed for a design that inherently suppressed the boom. The XB-1, Boom's demonstrator aircraft, flew supersonically in early 2025, years after the engine development began in mid-2022, highlighting the long and complex process of creating a novel engine.
The pivot to gas turbines and the AI energy crisis
The major turning point for Boom's financial viability came unexpectedly from the burgeoning AI industry's insatiable demand for electricity. Blake Scholl realized that their supersonic engine, designed for continuous high-temperature operation, was remarkably similar to a gas turbine. By removing the front fan and adding a small turbine connected to an electric generator, the engine could produce approximately 42 megawatts of power. This realization occurred in March 2025, coinciding with widespread reports of energy shortages for AI data centers. Scholl famously reached out to Sam Altman with a simple text: "Hey, would you want a 40-megawatt natural gas turbine?" Altman's immediate, enthusiastic response confirmed a massive, untapped market. This pivot meant Boom had inadvertently developed the perfect product for the AI boom, solving their funding problem by creating a high-margin revenue stream.
The decline of US aerospace and defense innovation
The conversation delves into the broader issues plaguing the aerospace and defense industries. Scholl points out that Boeing has not designed a new aircraft since 2004, and major turbine manufacturers are still using modified designs from the 1970s. This stagnation is attributed to a shift in corporate culture, driven by financial metrics like Return on Net Assets over free cash flow, leading to divestment of manufacturing and a focus on short-term Wall Street expectations. The prohibition of supersonic flight in the US in 1973 is cited as a major blow to commercial aviation innovation. In defense, the end of the Cold War removed the urgent need for innovation, turning programs into 'jobs programs' that supported existing companies without fostering true advancement. This has resulted in a 'lost generation' of engineers who might have pursued aerospace but instead went into software or other fields.
Boom's future-proofing and defense adaptability
Boom's core capability lies in its digital engineering and digital manufacturing approach, which allows for rapid adaptation. The company aims to move from a design concept to a manufactured turbine component in under 24 hours. This agility is crucial for defense applications, enabling Boom to pivot from civilian supersonic jets and power turbines to producing defense-critical components if needed. Their design philosophy emphasizes minimizing hard tooling that is difficult to reconfigure, ensuring flexibility. This stands in stark contrast to the slow, inflexible nature of established defense contractors, who may take 18 months to produce a part that Boom could theoretically produce in a day. This adaptability positions Boom as a potential asset for national defense, offering a more resilient and responsive industrial base.
Redefining the passenger experience through integrated design
Beyond the technical and business model innovations, Boom is fundamentally rethinking the passenger experience. Scholl, inspired by Apple's product design ethos, aims to eliminate the 'disgusting' aspects of current air travel, such as misaligned panels, visible wires, and dirty surfaces. The development of their own engine and airframe allows for integrated design, leading to significant improvements. A key example is the ability to redesign the cabin interior, including eliminating middle seats and enabling faster boarding and deplaning (aiming for 5 minutes each way). This holistic approach, where passenger experience drives engineering decisions, is a departure from traditional aircraft design, where such elements are often afterthoughts. The integration of features like Starlink Wi-Fi, designed directly into the airframe rather than as an add-on, further exemplifies this forward-thinking.
Mentioned in This Episode
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Common Questions
Boom initially partnered with Rolls-Royce because their engines were seen as easier to adapt for supersonic speeds, potentially saving them the significant cost and effort of developing a completely new engine from scratch. It was perceived as a way to leverage an established company's expertise and infrastructure.
Topics
Mentioned in this video
The company led by Brian Chesky, whose crisis management strategy inspired Boom's approach.
A major aerospace company whose lack of new aircraft designs and strategic decisions are discussed as a cautionary tale.
A defense contractor whose lack of readiness in producing interceptor missiles highlights the decay of the defense industrial base.
A former employer of the engineering team that Boom contracted for engine development.
Mentioned in relation to Jack Welch and the shift towards financial metrics over long-term investment.
A defense technology company mentioned as an example of a successful hard tech company.
Mentioned as an example of a successful hard tech company that developed its own core technology (rockets) rather than relying on established players.
A ride-sharing company mentioned to contrast capital expenditure with hard tech companies.
A major airline that placed a pre-order for Boom's supersonic aircraft, signaling market interest.
Another major airline that placed a pre-order for Boom's supersonic aircraft.
A company admired by Blake Scholl for its design philosophy, which influenced his approach to aircraft design.
A commercial manufacturer whose factories could have been converted for wartime production.
The last company to found a commercial aircraft company before a significant boom, mentioned in historical context.
A commercial manufacturer whose factories could have been converted for wartime production.
Mentioned in relation to Sam Altman, an early investor in Boom and CEO of the AI company.
Investor and CEO of OpenAI, who was approached by Blake Scholl about a potential market for turbines.
Credited with inspiring a new generation of engineers and entrepreneurs in aerospace.
CEO of Boom, discussing the company's journey and challenges in developing supersonic aircraft.
Mentioned in the context of efficient industrial practices and adaptation.
Former CEO of Boeing who declared an end to 'big ambitious projects'.
CEO of Airbnb, whose lecture inspired Scholl to pursue building their own engine.
Co-founder of Apple, admired for his attention to detail and design principles.
Pioneers of aviation, mentioned in the historical context of aircraft speed innovation.
The host of the Masters of Scale podcast.
Former CEO of General Electric, whose management philosophy influenced Boeing after the McDonald Douglas merger.
A designer who worked closely with Steve Jobs at Apple, known for his design contributions.
Founder of Oculus and founder of Anduril, mentioned as a source of insight into building adaptable defense technology companies.
A company that was initially partnered with Boom for engine development, but later terminated the agreement due to internal politics and strategic misalignments.
A company the contracted engineering team had previously worked with on power turbines.
An institution where Blake Scholl spoke to students about the lack of new aircraft designs.
A satellite internet service that is planned to be available on Boom's aircraft.
Boom's experimental supersonic aircraft, used for testing and development.
A retired supersonic passenger airliner, discussed as a historical example and a cautionary tale.
A mid-size turbine from General Electric, noted for being based on a 1971 aircraft engine.
Mentioned in the context of a potential conflict where US missile readiness is critically low.
Mentioned as a rival in the Cold War that spurred innovation in space and supersonic flight.
The location of the former Pratt & Whitney office that became the base for Boom's contracted engineering team.
The location of Pratt & Whitney's headquarters, where employees were asked to relocate.
Mentioned as the context for the return of urgent defense needs after a period of peace.
An internal Apple project name for a later iPhone concept, derived from an iPad project, which was ultimately chosen.
An internal Apple project name for an early iPhone concept that was essentially an iPod with a phone.
Software as a Service, mentioned as a business model that was dominant and made hard tech investments seem riskier.
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