Aviation and Space Startups funded by Y Combinator (YC) 2025

Momentus is a space infrastructure services company. As a first mover, Momentus will offer the most basic, foundational services that enable businesses to flourish in space. With their experienced team of aerospace, propulsion, and robotics engineers, Momentus makes and operates cost-effective and energy-efficient in-space transport and service vehicles that utilize water plasma propulsion technology. Momentus has service agreements in place with numerous private satellite companies, government agencies, and research organizations.

Wright Electric is building commercial electric airplanes for lower prices, higher safety, and zero emissions. The Wright 1 is a 186 passenger electric plane designed for routes like LA-SF and London-Paris. We work with airlines like easyJet and VivaAerobus.

Seaflight Technologies has developed a new form of Aerodynamic Flow Control for electrified aircraft that increases range and payload by 30%. That's the same performance improvement you'd get from hopping in a DeLorean to 2035 and coming back with batteries from the future. But it's available today - our tech has been derisked by testing supported by the National Science Foundation, the US Air Force, and the Australian Government. Our first product is a simple fixed-wing large cargo drone that is efficient enough to remove the "green penalty" currently associated with electric aviation. That's a step change from today's conventional platforms. First generation electric aircraft are heavy, expensive, complicated, and limited in terms of range and payload. In the entire history of aviation, that's never been a winning formula. When everyone already has access to the same batteries, materials, and motors, what really makes the difference? The answer is revolutionary aerodynamics, but in a form factor that suits today's operations and manufacturing. Beyond our own drone product line, we have partners across Aerospace helping incorporate our tech into their products. In the future, if you want to have the most efficient and cost-effective flying machine of any description, you'll need Seaflight's Flow Control inside.

Airhart is making airplanes anyone can fly. Our semi-autonomous tech will enable 10x more people to fly their own planes and make flying to Tahoe as easy as driving to the grocery store

Heart makes electric airplanes. We’re based in Sweden, and we’re developing a 19-passenger aircraft (EASA CS-23/FAA Part 23 certifiable). The plane will have an all-electric range of 250 miles and a backup generator for reserves and range extension. We have signed LOIs with Scandinavian Airlines SAS (the biggest airline in northern Europe), BRA and Wideroe for 86+ planes.

Astranis builds the world's most advanced satellites for high orbits. Their first product, MicroGEO, offers dedicated satellite broadband. But small, radiation-tolerant satellites can do far more than comms. With contracts in place with Space Force, NASA, and other government partners, Astranis is working across all higher orbits to support government science, PNT, and communications missions.

Tesseract is a provider of cost effective propulsion components and systems for in-space applications spanning commercial Earth-orbiting satellites, robotic exploration missions, and human spaceflight.

We are making reusable satellites for zero-g manufacturing. The next wave of pharmaceutical & semiconductor manufacturing will occur in orbit, and we already have $200M+ in LOI's from companies who want to get to space faster.

Boom Supersonic is transforming air travel with Overture, the world’s fastest airliner, optimized for speed, safety, and sustainability. Serving both civil and government markets, Overture will fly at twice the speed of today’s airliners and is designed to run on 100% sustainable aviation fuel (SAF). Symphony™, a Boom-led collaboration with industry leaders, is the propulsion system that will power Overture. Overture’s order book, including purchases and options from American Airlines, United Airlines, and Japan Airlines stands at 130 aircraft. Boom is working with Northrop Grumman for government and defense applications of Overture. Suppliers and partners collaborating with Boom on the Overture program include Collins Aerospace, Eaton, Florida Turbine Technologies (FTT), a business unit of Kratos Defense & Security Solutions, Inc., GE Additive, Safran Landing Systems, StandardAero and the United States Air Force. For more information, visit https://boomsupersonic.com Boom’s world-class engineering team comes from places including SpaceX, Boeing, Gulfstream, Virgin Galactic, Scaled Composites, NASA, and Bombardier. We have uniquely challenging and world-changing opportunities for the most talented aerospace engineers, designers, and business people.

Forerunner is your aerospace, defense, and hardware engineering copilot, helping you beat tight deadlines by automating critical engineering workflows. Our secure AI agents access data from tools like Atlassian Suite and Microsoft Office, then collaborate with hardware engineers to accelerate design and analysis.

Consus is your single source of truth for government specifications, standards, or handbooks. We verify the active revision of documents, notify you when documents are updated, and make it easy to extract the relevant information. Win new business or execute existing contracts faster with Consus.

HEO Robotics visually monitors satellites for governments and defence. We do this by transforming existing Earth observation satellites with software to image other satellites as they fly close by.

Care Weather collects the highest-accuracy global weather data to help governments and shipping companies adapt to extreme weather. The data is collected by Care Weather’s unique flat-panel radar satellite, which is 1000X more cost effective because it’s vertically integrated, gets more solar power, and sails on top of the atmosphere for a closer view of the surface. Our team includes CEO Patrick Walton (NASA Earth science fellow) and CTO Alex Laraway (mach 4 rockets). In the last 4 months, we built and launched the smallest radar satellite ever. We have $35M worth of LOIs, including one from the Air Force and others from cargo shippers. Care Weather is backed by Boost VC, Kickstart Seed Fund, Y Combinator, and more.

Relativity is building humanity’s multiplanetary future. We invented a new approach to design, build, and fly our own rockets, starting with Terran 1 – the world’s first entirely 3D printed rocket, and Terran R, our next generation medium-heavy lift fully reusable launch vehicle. As a vertically integrated technology platform, Relativity is at the forefront of an inevitable shift toward software-defined manufacturing. By fusing 3D printing, artificial intelligence, and autonomous robotics, we are pioneering the factory of the future. Disrupting 60 years of aerospace, Relativity offers a radically simplified supply chain, building a rocket with 100x fewer parts in less than 60 days. We believe in a future where interplanetary life fundamentally expands the possibilities for human experience. Our long-term vision is to upgrade humanity’s industrial base on Earth and on Mars.

Prime Lightworks Inc. manufactures electric propulsion systems for space satellites.Their goal is to engineer new possibilities in space while drastically reducing cost and waste.

Our planes fly 10 times further than battery electric alternatives, with a lower operating cost than fossil fuel powered aircraft. Our first product is a 15 seat aircraft with a range of 800 km that enters service in 2026 with launch customer Skytrans. Our team has over 85 years of aerospace experience and have developed, flight tested and certified aircraft at Google X, magniX, Heart Aerospace, Ampaire, Airbus, Boeing, Bombardier and Gulfstream. We have $145M in aircraft LOIs from 7 airlines in the US, Europe and Australia.

Astro Mechanica has invented a new kind of jet engine – the Electric Adaptive Engine. Unlike any existing engine, it’s efficient at every speed. Because it’s efficient at every speed, it enables us to build a new jet aircraft with unique capabilities. It can launch payloads to orbit for 3x cheaper or fly 3x faster than regular passenger aircraft.

Radical makes high-altitude solar-powered aircraft. Our aircraft fly at 70,000 feet, autonomously navigating in the stratosphere. They can be used to provide cell service, collect multi-spectral imagery, or to carry weather and climate sensors. Our aircraft offer an inexpensive, zero-emissions way to connect and observe earth like never before. Prior to Radical, our founders worked together for 6 years developing Amazon’s delivery drones.

Enhanced Radar is building better, safer air traffic control systems.

(Formerly known as Lumen Orbit) Starcloud is building a network of megawatt-scale data centers in space, scaleable to gigawatt capacity, to be able to train large models like GPT6. Falling launch costs give us access to abundant energy, passive cooling, and the ability to rapidly scale in space. In Partnership with NVIDIA's Inception Program, we are launching our demonstrator satellite in July 2025, which will have 100x more powerful GPUs than have ever been operated in space.

Pyka’s goal is to provide society with a new form of safe, clean, and cost-effective transportation enabled by autonomous electric aviation. To get there, we’re taking a different approach than most. We're applying our technologies to every industry where autonomous electric aircraft can be useful, starting with the highest value and most dangerous jobs. In doing so, we're building game-changing products manufactured at scale, while perfecting the safety, reliability, and capabilities of our autonomy engine and electric propulsion systems. We design, develop and manufacture an ecosystem of technologies including proprietary flight control software, avionics, high power density motors, motor controllers, batteries, and custom carbon-fiber composite airframes. Today, we supply autonomous electric aircraft for cargo transport and crop protection to real-world customers across four separate continents and have secured industry-first regulatory approvals from the FAA. Our cargo aircraft enables remote connectivity, enhances express delivery networks, and ensures fast and reliable shipping of critical supplies to areas in need. Our crop protection aircraft offers agricultural services providers and farmers an autonomous tool to make aerial application safer, more precise, and less harmful to surrounding environments. Both vehicles are highly economical to operate, easy to deploy, and significantly reduce C02 emissions in their respective industries. What you work on at Pyka makes people’s lives better now and brings the future of electric aviation one step closer each day.

Beyond Aero was founded to meet the challenges of climate change and is developing the first hydrogen-powered electric business aircraft. The company is on a mission to make aviation electric, starting with business aviation since private jet are the most emissions-intensive segment per passenger, producing ten times more CO2 per person than commercial flights. Beyond Aero has hit significant technical milestones, achieving France's first manned fully hydrogen-electric flight earlier this year and appointing Luiz Oliveira, former advisor on Embraer’s hybrid hydrogen program, as Chief Engineer. Beyond Aero has secured $914 million in Letters of Intent (LOIs) for 108 aircraft and earned multiple awards, including Brilliant Minds and the Sustainable Aviation Challenge by the World Economic Forum, joining the First Movers Coalition.

Instinct is making satellites to provide GPS navigation to companies landing on or orbiting the moon. By downsizing the current navigation architecture into a cubesat format we can drastically lower both manufacturing and launch costs, allowing for quicker deployments and more resiliency within the system.

Odys Aviation (formerly Craft Aero) builds vertical take-off and landing aircraft for major airlines. We cut travel time in half on the world’s busiest routes by using city helipads and local airports. The company founders are electric propulsion and automotive manufacturing experts who have spent their careers electrifying transportation systems at Virgin Hyperloop, GoogleX, Volvo, and Fisker Automotive. We’ve won two USAF Agility Prime contracts, have pre-orders and options for more than 1,000 aircraft.

Navier AI is making CFD 1000x faster with their ML-based solver. Physics simulations, such as Computational Fluid Dynamics (CFD), are essential across many industries ranging from the design and analysis of aircraft, to weather prediction, to the development of medical devices. Today’s simulation tools use explicit numerical solvers for physical equations, such as the Naiver-Stokes equations. These solvers are complex to setup and can take ages to produce results. Navier AI is building 1000x faster simulations using physics-ML solvers. Navier AI's fast CFD platform will enable engineers to quickly explore design spaces and perform analysis-in-the-loop design optimization. They are lowering the barrier to entry for aerospace and mechanical engineers to create high performance designs.

REGENT is building a new mode of transportation that will redefine regional mobility by mid-decade. Their first product, the seaglider, is an all-electric, hydrofoiling boat-plane that operates within a wingspan of the water's surface. By flying low on a cushion of air, seagliders unlock the ability to fly twice as far as an electric aircraft, while being regulated by maritime authorities enabling market entry for a fraction of the cost. REGENT has de-risked seaglider technology with a ¼-scale, 400 lb, flying demonstration vehicle and a full-scale wing test section. By 2024, REGENT will fly humans on the first full-scale prototype seaglider. By mid-decade, REGENT’s customers - airlines and ferry companies – will begin commercial seaglider service on the 12-seat initial product. In just two years, REGENT has accumulated $8B in provisional orders (including firm deposits) proving the potential of the $25B+ initial market. REGENT, a team of 40, is led by MIT-trained, ex-Boeing engineers Billy Thalheimer and Mike Klinker. REGENT has raised $50M to date from the likes of Thiel Capital, Founders Fund, Mark Cuban, Y Combinator, and includes strategic investment from Japan Airlines, Hawaiian Airlines and Mesa Airlines.

Basalt Tech is a spacecraft OS company based in San Francisco. We're building Dispatch: An OS which allows different types of satellites to work together, and produces optimized instructions for fleets of spacecraft. The company is founded by Max Bhatti and Alex Choi, lead engineers at the MIT CubeSat program. Previously, the duo worked as systems engineers at SpaceX, and the UK Ministry of Defense. Basalt Tech recently received its seed investment as part of the Y Combinator W24 batch, and is currently in technical development.

Spaceium builds fully automated space stations to refuel and repair spacecraft. We have secured $86.1 million in binding commercial contracts and have an additional $230 million in the pipeline. Additionally, we have 1 billion dollars in letters of intent. We have successfully tested our hardware, which will launch to space next year. Our fully automated space stations will efficiently store and transfer both cryogenic (extremely cold) and non-cryogenic fuels with zero loss during storage and transfer. And they can transfer fuel seamlessly to any spacecraft design using our proprietary modular robotic arm. Our customers include launch vehicles, orbital transfer vehicles, moon landers, and spacecraft that benefit from increased payload capacity and extended travel capabilities. Our long-term vision is to build service hubs along the space superhighway to connect Earth to Moon and Mars and help humanity to become multi multi-planetary species

Our focus is on developing the smallest, fastest heavy lift optionally piloted VTOL aircraft. Our aircraft can be operated in urban environments with no risk of rotor strikes - we don't use rotor systems! Ship anything from downtown LA to downtown San Diego in 20 mins!

With five issued patents covering our core business lines, and more than a dozen additional patents pending this year and more than $5M in revenue, TransAstra is developing the technologies that will drive the rapidly expanding space economy. Our breakthrough Omnivore propulsion system can propel spacecraft, including our Worker Bee commercial OTV with water or virtually any other fluid as a propellant using only concentrated sunlight as a power source. Omnivore is faster, cheaper, and more practical than electric propulsion while being substantially less expensive, safer, and more operationally flexible than legacy chemical propulsion systems. Our Sutter Telescope System can identify and locate resource-rich asteroids and orbital debris that existing technologies can’t find and works synergistically with our Worker Bee OTV for orbital logistics. For government customers, Sutter can identify dark fast-moving objects between Earth and the Moon which currently evade detection, a critical issue for national defense and a key need of the Space Force. We are already using Sutter in ground-based observatories and will begin commercial sales of Sutter SDA data next month having tracked dozens of faint moving objects in space already. Once launched into space, Sutter will be 300,000 times more cost effective than any other known telescope design and will revolutionize sense making in space.

Turion Space is building spacecraft to move things around in space and image space objects when they’re not, and focused on developing the dual-use technology required to ensure a sustainable future in space. They aim to build a strong foundation selling space domain awareness imagery data while advancing their technology towards an affordable solution for orbital debris removal and eventually asteroid mining. The founding team originates from SpaceX, and after going through the Y-combinator accelerator in summer 2021 went on to raise a $6.2M seed round and is launching their first DROID satellite in early 2023.

Bifrost Orbital is building an advanced, enhanced network of optical relay satellites to deliver 24/7 in-orbit connectivity to satellite companies with their low orbiting satellites. Our approach is designed to offer increased uptime and data rates for telemetry related operations.

We're designing swarms of tiny satellites which will work together to create the first real-time, high-resolution 3D model of the earth. By using clusters of satellites to image the same place on the earth at the exact same time, we can improve image quality by more than 60x over conventional techniques. This technology will massively increase the amount of affordable, high-quality 3D data, enabling a host of new applications across an array of industries, including AR/XR/Autonomy, Defense, Climate/ESG, and Insurance Analytics.

Velontra is building a hypersonic space plane that can takeoff from anywhere in any weather. This horizontal takeoff increases launch reliability and enables customers to directly access any orbit. Our air-breathing propulsion system is up to 6 times more fuel efficient than any rocket, and uses oxygen from the air which creates thousands of pounds of additional payload capacity. We have millions in current government/commercial contracts and LOI’s. We have assembled a team of industry experts, government senior executives, and a NASA astronaut. The hypersonic space plane will work by taking off from any runway with a jet propulsion system. Next, it will climb to over 100,000’ and Mach 5. At this point, it will launch a 2nd stage rocket directly into the desired Low Earth Orbit. Velontra is “boldly going where no one has gone before.”

Elodin creates flight software, simulations, and hardware for drones, satellites, and defense.

Alba Orbital is building the world's largest earth observation constellation, imaging everywhere on earth, every 15 minutes. We can see events within minutes such as wildfires in real time and have signed >$85m of LOIs, with both government and commercial customers paying pre-orders for imagery. To date we have launched 41 satellites into orbit (more than any other seed stage company in history), with more launching in 2024 onwards. We have launched a number of technology demonstration imaging satellites called Unicorns, which are the world's most advanced satellite under 1kg ever flown in orbit.

Orbital Operations is developing a high thrust, reusable space vehicle for satellite defense. We protect critical satellites, like GPS and Military communication satellites, from adversarial threats, like China and Russia. Our vehicle will use the exact same propulsion systems that launch vehicles have used for decades by implementing a cryogenic management system. This will give us over 100x the thrust or current in-space propulsion. Ross and I have over 15 years of combined aerospace experience across NASA, Aerojet Rocketdyne, SpaceX, Blue Origin, and Relativity Space. We’ve worked side by side for more than 3.5 years developing propulsion systems, turbomachinery, and building our own respective engineering teams. We are currently working on the first demo of our unique cryo management system and intend to launch an operational vehicle by 2027.

Albedo is the first space company to commercialize the new orbit regime of VLEO (very low earth orbit). VLEO enables enhanced data quality for numerous earth observation modalities. Our first VLEO satellite, named Clarity and built in-house, is launching in 2025 and will capture visible & thermal images at a resolution that can only be obtained today from drones/planes (commercially) or classified National Security systems. The world is rapidly changing and a new level of visibility and transparency is required to solve some of our largest problems. Albedo’s 10cm visible and 2m thermal imagery will fuel insights for industries such as mapping, insurance, utilities, solar, agriculture, carbon offsets, infrastructure sustainability, national security, and much more.

At H3X, we are making the lightest, high-power electric propulsion systems in the world to enable a large-scale revolution in aircraft electrification. Our first product is a 250-kW (335 HP) integrated motor drive in an 18 kg package. It combines the electric motor, inverter, and gearbox into a single powerful unit and is the culmination of patent pending innovation in multiple areas.

Stoke Space delivers goods to and from orbit using 100% reusable rockets designed to fly daily.

Wyvern is a space data company that will capture the highest resolution hyperspectral images from satellites that cost 100X less than satellites using traditional telescopes.

Hubble is building a global satellite network that any Bluetooth-enabled device can connect to, even without cellular reception. Our mission in life is to get a billion devices connected to the network and unlock a new era of human-machine collaboration.

Talyn is making long-range electric vertical take-off and landing (eVTOL) aircraft for cargo. We get fixed-wing performance with VTOL capability by making an electric fixed wing aircraft that is caught mid-air with a custom winged drone, enabling it to take-off and land vertically.