Prominent solo investor Lachy Groom has backed a Bengaluru startup attempting an unusually ambitious aerospace feat: keeping an aircraft in the sky for more than a year by harvesting energy from ocean winds.

Alteon, founded by 20-year-old Samay Sanghvi, announced Tuesday that it raised $2.5 million in a pre-seed round led by Groom, with participation from Together Fund. The funding will support the startup's development of small, fixed-wing autonomous aircraft inspired by dynamic soaring, a technique albatrosses use to extract energy from the wind.

According to Sanghvi, Groom decided he wanted to invest within the first 30 minutes of their initial meeting.

Dynamic soaring: The albatross advantage

Dynamic soaring is a flight maneuver that allows an aircraft to gain energy by repeatedly crossing boundaries between air masses moving at different velocities. Albatrosses and other seabirds use this technique to travel vast distances over the ocean with minimal flapping, extracting energy from wind shear above the water's surface.

Conventional aircraft must carry all the fuel or battery power required for a mission, which severely limits endurance. Alteon is trying to break that limitation by designing its autonomous aircraft to use dynamic soaring as a primary energy source. In theory, an aircraft that can efficiently harvest energy from the wind could remain airborne for months or even years at a time.

“Once you build airplanes that can stay in the air for more than a year, there are millions of things you can do with them,” Sanghvi told TechCrunch. Alteon plans to initially use its aircraft for maritime surveillance, giving governments real-time visibility into activity in their waters.

How Alteon's aircraft works

The initial plan is to build an aircraft with around a 3-meter wingspan that flies close to the ocean's surface, climbs, turns through faster-moving air, and repeats the cycle to extract energy from the wind. Eventually, Alteon plans to use its propellers as turbines, converting some of that energy into electricity to recharge onboard batteries.

This approach is radically different from conventional solar-powered or battery-electric long-endurance aircraft, which rely on sunlight or stored energy. Dynamic soaring, by contrast, uses the kinetic energy of moving air directly, potentially enabling flights that outlast traditional power sources.

Alteon has not yet demonstrated sustained flight using energy harvested through dynamic soaring. However, the company completed a recent test of its autonomous flight system over the Bay of Bengal. During that test, the aircraft autonomously completed seven O-shaped cycles at more than 62 miles per hour, all while flying within 1 meter of the water's surface.

Sanghvi said that staying very close to the waves is essential. Wind speeds are slower near the surface and faster at higher altitudes, and the difference between those layers is what dynamic soaring exploits. Flying that low, however, is challenging because the aircraft must avoid waves and cope with the turbulent air created by the ocean's motion.

Expert perspectives on Alteon's progress

Dr. Gabriel Bousquet, a Silicon Valley-based aerospace and robotics engineer who researched dynamic soaring during his PhD at MIT, called Alteon's low-altitude flight over water a “promising first result.” But he noted that the harder challenge is proving the aircraft can reliably extract enough energy from real-world winds to sustain flight for extended periods.

“Flying low enough to harvest that energy safely is particularly difficult,” Bousquet said, because the aircraft must contend with turbulence, waves, spray, rain, and changing light conditions while continuously sensing and reacting to a moving ocean surface.

Dr. Bharath Swaminathan, who earned his PhD from IIT Madras studying the stability of dynamic soaring, said the underlying physics is well established and called Alteon's effort commendable. Keeping an aircraft airborne for several days using dynamic soaring would itself be “a very big step, and a big achievement,” he said.

Still, Swaminathan cautioned that while large-scale wind conditions may be predictable, local wind shear and turbulence can vary substantially, complicating an aircraft's ability to continuously extract energy from the wind. Some of those challenges, he suggested, may only emerge through real-world flight testing.

A young founder with a history of persistence

Sanghvi began working on what would become Alteon straight out of high school in 2023. He taught himself to build aircraft by making and crashing radio-controlled models before developing early prototypes. He formally founded Alteon in 2025 and received early backing from Emergent Ventures and 1517.

Alteon now has a team of 20 in Bengaluru and operates from a 10,000-square-foot facility. According to Sanghvi, the startup is building four to five aircraft a week for testing and has conducted more than 200 test flights in the past 30 days alone.

That rapid iteration has allowed Alteon to work through many practical issues, from control algorithms to airframe durability. Each test flight helps refine the autonomous systems that must eventually handle dynamic soaring without human intervention.

The road to energy-neutral dynamic soaring

Alteon's next major milestone is what Sanghvi calls “energy-neutral dynamic soaring.” This would allow the aircraft to fly continuously with its propulsion switched off, extracting enough energy from the wind to remain aloft. Achieving this milestone would validate the core physics and engineering of the company's concept.

The implications of such a breakthrough extend far beyond maritime surveillance. Aircraft that can remain aloft for a year or more could transform communications relays, environmental monitoring, storm tracking, and disaster response. They could also provide persistent coverage of remote ocean regions where satellites and conventional drones have limitations.

For Lachy Groom, the bet is as much about the team as the technology. Groom, known for early investments in companies like Stripe and a number of frontier-tech startups, has a track record of backing founders tackling extremely difficult engineering problems.

“Ambitious problems are always going to come with risks,” Groom said. “For me, it came down to believing Samay and the Alteon team are the ones to figure them out.”

The aviation industry has long dreamed of aircraft that can stay airborne indefinitely. During the Cold War, the United States developed the Lockheed U-2 and later the SR-71 for high-altitude reconnaissance, but both required massive logistical support and frequent refueling. In recent years, companies have experimented with solar-powered high-altitude pseudo-satellites such as Airbus's Zephyr and Facebook's Aquila, but these aircraft rely on sunlight and heavyweight batteries, which limits their endurance and weather tolerance in certain regions.

Dynamic soaring takes a different path. Instead of fighting the wind, it embraces it. The albatross, with wingspans reaching 11 feet, routinely travels hundreds of miles per day without flapping, using precisely the technique Alteon aims to replicate. Scientists and engineers have studied dynamic soaring for decades, and some radio-controlled glider enthusiasts have used it to keep their models airborne for extended periods, but no one has yet built an autonomous aircraft capable of doing so reliably for days, let alone a year.

One of the reasons has been the sheer complexity of the maneuver. Dynamic soaring requires precise control at high speeds and low altitudes, often within a few meters of the ocean surface. The aircraft must sense its altitude continuously, adjust its flight path many times per second, and do so with very little margin for error. A wave height of a few feet or a sudden gust of turbulence can quickly end a mission.

Alteon's early test flights suggest the control systems are improving. The Bay of Bengal flights demonstrated an ability to hold altitude within 1 meter while maintaining speeds above 62 mph, which is necessary for the wind-shear harvesting maneuver. Sanghvi says the company chose the Bay of Bengal for testing because it offers strong and relatively consistent wind conditions, as well as open water with clear airspace.

The startup is not just working on the flight control system. Materials and energy management are equally important. The aircraft must be light enough to achieve dynamic soaring but strong enough to survive weather and heat. Its sensors must consume very little power, and the eventual propeller-turbine system must efficiently convert wind energy into electricity without adding excessive weight or drag.

Sanghvi acknowledged these engineering challenges but said the team's rapid iteration gives him confidence. “We have learned more in the last 30 days than most aircraft startups learn in a year,” he said. “Every crash teaches us something. Every test changes the next design.”

Beyond the technical hurdles, Alteon will also need to navigate regulatory requirements, especially if it plans to operate aircraft over the oceans for months at a time. Civil aviation authorities have developed rules for drones, but an autonomous aircraft that stays aloft for a year and flies over international waters will likely require new frameworks. For now, Sung backers seem comfortable with the risk.

The $2.5 million pre-seed is modest by aerospace standards, but Alteon has no immediate plans for expensive launches or full-scale demonstrators. Instead, the startup is focused on incremental flight testing and refining the algorithms that make energy-neutral soaring possible.

Groom's involvement may also help Alteon attract follow-on funding as it approaches its demonstration targets. Together Fund, a SaaS-focused venture capital firm, participating in the round signals that investors with a broader startup focus are taking the concept seriously.

For the aerospace research community, Alteon's progress is being watched with both excitement and caution. If the startup succeeds, it would not only shatter endurance records but also open new explorations of atmospheric physics and aeroelasticity. If it fails, the lessons learned will still be valuable.

Sanghvi is unmoved by skepticism. He sees Alteon as a first step in a longer journey toward more autonomous, more capable aircraft that can operate indefinitely in dynamic environments. “The aircraft are just the beginning,” he said. “The systems we build to control them will have applications far beyond what we're doing today.”

Alteon's immediate timeline appears ambitious. The company aims to demonstrate energy-neutral dynamic soaring within the coming months, and its larger goal of full-year endurance remains years away. It remains to be seen whether the physics and engineering will align as neatly as the company expects, but for now the startup is moving quickly from drawing board to ocean.

Source: TechCrunch News