How does Stoke Space's Andromeda capsule survive re-entry?

The Andromeda capsule uses a custom heat shield that employs cold liquid hydrogen flowing through a heat exchanger to absorb extreme re-entry heat. Additionally, 24 small thrusters help control its descent and landing.

Who are the founders of Stoke Space and where did they work before?

The founders are Andy and Tom, who met while working as jet propulsion engineers at Blue Origin. They left to start Stoke Space in 2019, driven by the problem of disposable rockets.

What were the biggest challenges in starting Stoke Space?

The founders faced significant challenges, including the decision to leave secure jobs with young families, the difficulty of raising funds during the pandemic market shutdown, and the steep learning curve of starting a company from scratch.

How did Stoke Space develop its early prototypes?

They began by building and testing a prototype engine in a shipping container in Tom's backyard. This hands-on approach allowed them to demonstrate hardware progress to potential investors early on.

How much has Stoke Space raised and what is their operational philosophy?

Stoke Space has raised approximately $990 million to date. They emphasize operating very efficiently and focus on rapid iteration by making most parts in-house, which allows for quicker learning and development cycles.

What role does software play at Stoke Space?

Software is critical not only for the rocket's functionality but also for company operations. They developed a proprietary tool called Bolt Line to manage everything from manufacturing and testing to maintenance tracking, bridging the gap from garage operations to regulatory compliance.

Key Moments

Inside The Startup Building Reusable Rockets

Y Combinator

Science & Technology6 min read16 min video

Jan 8, 2026|33,969 views|1,206|70

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Key Moments

TL;DR

Stoke Space aims for fully reusable rockets, tackling the second stage heat shield to enable daily launches, though this ambitious goal has already required $990 million in funding.

Key Insights

Stoke Space is developing fully and rapidly reusable rockets, including the second stage (Andromeda capsule), which typically disintegrates during re-entry due to speeds of 17,000 mph and temperatures exceeding 2700° F.

The company has raised approximately $990 million to date for its operations and development.

Stoke Space's Nova rocket features a high-performing, fuel-efficient engine designed for longevity and rapid reusability, a critical component for their ambitious goals.

The Andromeda capsule utilizes a custom heat shield with flowing liquid hydrogen and a system of 24 small thrusters to manage re-entry heat and control descent.

Stoke Space has developed an internal operations software called 'Bolt Line' to manage vehicle data, maintenance, and scaling from garage operations to FAA oversight.

The company plans its first orbital launch from Complex 14 at Cape Canaveral later this year, a site historically used for significant early space missions.

The challenge of a fully reusable rocket

Stoke Space is tackling what they call the 'holy grail' of rocket science: achieving full and rapid reusability for rockets, akin to aircraft. While current industry advancements allow for the reuse of the first stage, the second stage remains a disposable component. This is primarily due to the immense challenges posed by re-entry at speeds up to 17,000 mph, which generates extreme heat exceeding 2700° F. Stoke Space's ambition is to make the entire rocket, including the second-stage capsule, capable of surviving this brutal descent and being reused, potentially enabling daily launches and a transformative shift in space access. This focus on complete reusability aims to dramatically lower costs, improve availability, and increase the reliability of spaceflight compared to the current paradigm where multi-million dollar rockets are built, tested, and then discarded.

Nova and Andromeda: Architecting for reusability

The Nova rocket is designed as a two-stage system to reach orbit. The first stage is intended to perform similarly to existing reusable rockets, launching the vehicle and then either landing downrange or back at the launch site. A key technological achievement for Stoke Space is its first-stage engine, which boasts exceptionally high fuel efficiency, contributing to its longevity and rapid reusability. The second stage, named Andromeda, is responsible for the final push to orbit. Its critical innovation lies in its re-entry capability. Unlike conventional rockets, the Andromeda capsule is designed to close up after payload deployment and re-enter Earth's atmosphere. Here, a custom heat shield system employs a heat exchanger circulating cold liquid hydrogen to absorb extreme temperatures. Upon descent, 24 small thrusters are used to control its speed and landing angle. This comprehensive approach to reusability in both stages is central to Stoke Space's strategy.

From backyard testing to a major funding round

Stoke Space's journey began with co-founders Andy Lapsa and Tom Feldman, former jet propulsion engineers at Blue Origin, who left in 2019 with the audacious goal of solving rocket reusability. An initial period of uncertainty led them to focus on this core problem, believing they had a viable solution. They faced significant personal risk, leaving comfortable jobs with young children to start the company. Their early efforts involved substantial hands-on work, testing a prototype engine in a shipping container in a backyard. They managed to build their initial test facility within approximately two months. Fundraising proved to be a significant hurdle, especially with the onset of the pandemic, which caused the market to shut down. Their participation in Y Combinator was crucial for gaining traction, learning the fundraising process, and securing their first investment. To date, Stoke Space has raised approximately $990 million, a testament to the perceived potential of their technology, even as they emphasize operating with high efficiency.

Rapid iteration and in-house manufacturing

A cornerstone of Stoke Space's development philosophy is rapid iteration, driven by an emphasis on speed and the ability to make most parts in-house. They acknowledge that perfection through analysis alone is impossible in rocket science. The critical factor is the speed at which they can learn from failures and implement improvements. This requires a manufacturing capability that can quickly produce replacement parts. Their 168,000 sq ft factory, established in 2024, is designed to build approximately seven vehicles per year and houses capabilities for avionics, electronics, engine assembly, additive manufacturing, and structures. This integrated approach allows them to significantly shorten the development cycle. For instance, a process that might typically take a month—involving testing, teardown, modification, and re-testing—can be condensed to just a day or two by having the necessary manufacturing and integration capabilities on-site. This speed is crucial for efficiently tackling the complex technical challenges.

The strategic role of bespoke software

Stoke Space recognized early on that software would be as critical to their mission as hardware. Bridging the gap from garage-scale operations to building government-certified vehicles for government payloads requires robust systems. For reusable rockets, tracking the performance, wear, and maintenance needs of components across numerous flights is paramount. This contrasts sharply with expendable rockets, where post-launch data is limited. Stoke Space developed its own foundational operations software, named 'Bolt Line,' to manage this complexity. This tool is integral to their operations, allowing for the automation of data logging from factory workers, the analysis of vehicle performance, and predictive maintenance scheduling. They are also looking to leverage advancements in AI to further streamline factory work and data management, ensuring the seamless integration of information across engineering, manufacturing, and flight operations.

Establishing a launch presence at Cape Canaveral

Comprising their ambitious plans, Stoke Space is establishing a launch site at the historic Complex 14 in Cape Canaveral, Florida. This location is notable for being the launch site of John Glenn's historic 1962 orbital mission, marking him as the first American to orbit the Earth. The construction project at Cape Canaveral is progressing well and is a vital piece of their strategy. Concurrently, they are finalizing the development and qualification of both their first and second-stage engines. Structural testing of various vehicle components is also underway, including testing at cryogenic conditions conducted at their Moses Lake facility. Furthermore, they are rigorously testing their avionics and software stack through hardware-in-the-loop simulations, ensuring the integrated systems are robust and ready for spaceflight.

The vision for a daily launch cadence

If Stoke Space achieves its ambitious goals, the vision is to fly their rockets every single day. This level of operational cadence would represent a paradigm shift in space accessibility and commercialization. The founders' conviction stems from believing that the core idea of full reusability is fundamentally sound and worth pursuing, regardless of the ultimate outcome. They feel a responsibility to explore this concept because of its potential to unlock unforeseen applications and industries, likening it to the 'iPhone app store moment' where new possibilities emerge once a fundamental capability is widely available. Their core belief is that this level of reusability is not just technically feasible but necessary for the continued growth and diversification of the space economy. This profound conviction fuels their persistent efforts to overcome the immense technical and financial hurdles inherent in their mission.

Mentioned in This Episode

●Products

●Software & Apps

●Companies

●Organizations

●Concepts

●People Referenced

Building Reusable Rockets: Key Principles

Practical takeaways from this episode

Do This

Focus on full and rapid reusability from day one to decrease cost and increase availability.

Develop high-performing rocket engines with long life and rapid reusability in mind.

Design stage 2 capsules with robust heat shields and thrusters to survive re-entry.

Build in rapid iteration capabilities by manufacturing parts in-house.

Leverage software for operational efficiency, maintenance tracking, and data abstraction.

Plan for failure and ensure quick learning cycles from test stand results.

Secure funding and build a network through accelerators like Y Combinator.

Develop a custom operations tool (like Bolt Line) to manage complex processes.

Avoid This

Treat rockets as single-use expendable hardware.

Underestimate the challenge of raising capital, especially for hardware ventures.

Rely solely on PowerPoint presentations without demonstrating hardware progress.

Neglect the critical role of software in managing operations and scaling.

Depend on external suppliers for critical parts if rapid iteration is needed.

Common Questions

Stoke Space aims to build fully and rapidly reusable rockets, similar to aircraft reusability. This goal is driven by the desire to significantly lower the cost, improve the availability, and enhance the reliability of access to space.

Topics

Technology & Innovation Science & Mathematics Business & Entrepreneurship Space Exploration Operational Efficiency Startup Funding Hardware Development Rocket Engineering Reusable Rockets Aerospace Startups Lean Manufacturing

Mentioned in this video

Concepts

iPhone app store

Used as an analogy for the transformative potential of fully reusable rockets, suggesting it will unlock numerous new applications and ideas.

Software & Apps

NOvA

Stoke Space's two-stage-to-orbit rocket, designed for rapid reusability. The first stage is similar to other rockets but features high-performing engines for landing, while the second stage (Andromeda capsule) handles the trip to orbit.

Bolt Line

Stoke Space's custom-built operations software, designed to manage everything from manufacturing to maintenance, abstracting and distributing critical information across the company.

Companies

Stoke Space

A startup focused on building fully and rapidly reusable rockets with aircraft-like reusability, aiming to decrease costs and improve access to space.

Blue Origin

Aerospace company where the founders of Stoke Space, Andy and Tom, met while working as jet propulsion engineers.

Y Combinator

A prestigious startup accelerator that Stoke Space joined, providing crucial network access, mentorship in fundraising, and momentum for their seed round.

People

John Glenn

First American to orbit Earth, whose historic launch took place from Complex 14 in Cape Canaveral, the same site Stoke Space is developing its launch facilities.

Locations

Seattle

The major city near Kent, Washington, where Stoke Space is headquartered.

Kent, Washington

The location of Stoke Space's headquarters, noted as an emerging hub for space tech startups near Seattle.

Cape Canaveral, Florida

Location of Stoke Space's new launch site at historic complex 14, the same site where John Glenn first orbited Earth.

Moses Lake

Location of a Stoke Space facility where structural and cryogenic testing of rocket components is conducted.

Organizations

FAA

The Federal Aviation Administration, mentioned as the regulatory body that will oversee government payloads or human flights on Stoke Space's vehicles, highlighting the company's need to bridge from garage operations to regulated aerospace.

Andromeda

The stage 2 capsule of Stoke Space's Nova rocket, designed to survive re-entry using a custom heat shield and thrusters, enabling full reusability of the rocket system.

Products

Starlink

A satellite internet constellation operated by SpaceX, mentioned as taking up a significant portion of available commercial space launch capacity.