Prominent solo investor Lachy Groom has backed a young Indian startup pursuing one of aviation's more unusual goals: an autonomous aircraft that can stay in the sky for more than a year by harvesting energy from ocean winds.

Bengaluru-based Alteon, founded by 20-year-old Samay Sanghvi, said on Tuesday that it raised $2.5 million in a pre-seed round led by Groom, with participation from Together Fund. The money will support the development of small, fixed-wing aircraft designed around dynamic soaring, a flight technique used by albatrosses to extract energy from the wind. Sanghvi told reporters that Groom decided he wanted to invest within the first 30 minutes of their first meeting.

What is dynamic soaring?

The principle behind Alteon's approach comes from dynamic soaring, an aerodynamics technique that exploits wind shear. Wind shear is the boundary layer where wind speed changes rapidly with altitude. An aircraft can gain energy by repeatedly moving between slower-moving air near the surface and faster-moving air higher above. When it climbs from slow air into fast air, it gains kinetic energy relative to the ground; when it turns and dives back through the shear layer, it can capture additional energy from the wind.

Albatrosses have long been observed using this method to travel huge distances across oceans while expending very little body energy. Scientists have studied dynamic soaring for decades, but most practical aviation has not adopted it because aircraft systems and missions are normally built around fuel or batteries. Conventional planes must carry all of the energy needed for a flight, and even long-endurance drones are limited by their power sources.

Alteon is trying to break that limitation. Its small, fixed-wing autonomous aircraft are designed to fly close to the ocean surface, climb into faster-moving air, turn, descend, and repeat the cycle continuously. The company plans to start with aircraft with a wingspan of around three meters, operating over open water where wind shear is consistently available.

Maritime surveillance mission

If Alteon succeeds, the applications could be broad. Sanghvi said that once aircraft can stay in the air for more than a year, there are millions of things they can do. The startup's first planned market is maritime surveillance, providing governments with real-time visibility into activity in their waters.

Ocean monitoring remains a difficult problem for defense and civilian agencies. Illegal fishing, smuggling, pollution, piracy, and unauthorized vessel activity all take place across vast stretches of ocean. Satellites can provide periodic imagery, but they cannot loiter over one area. Ships are slow to move from place to place. Manned aircraft are expensive to fly for long periods. Conventional drones need fuel or recharging, and their endurance is often measured in hours rather than months.

An autonomous aircraft that can remain above a chosen area for weeks, months, or more than a year could offer a new kind of persistent presence. It would not require a support ship or a nearby runway if it can harvest energy from the wind while staying aloft. That is the promise Alteon is working toward.

How Alteon plans to make it work

The aircraft Alteon is developing will initially use dynamic soaring to stay airborne in its most efficient state. During the soaring phase, the propulsion system would be switched off. The aircraft would ride the wind layers, climbing and descending in repeated cycles while moving forward over the ocean.

In a later phase, Alteon intends to use its propellers as turbines in flight. When the aircraft has excess speed or encounters suitable wind conditions, the propeller can spin to generate electricity and recharge the onboard battery. The stored energy would allow the aircraft to climb, maneuver, or maintain flight in periods when wind shear is not strong enough.

Sanghvi describes this as a path toward what he calls energy-neutral dynamic soaring. In that state, the aircraft would fly continuously with its propulsion switched off, extracting enough energy from the wind to remain aloft indefinitely. That milestone would represent a major shift in how endurance is measured for small unmanned aircraft.

Early flight tests

Alteon has not yet demonstrated that its aircraft can sustain flight solely through energy harvested from dynamic soaring. The company did, however, complete 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 speeds above 62 miles per hour while flying within one meter of the water surface. Flying that low is significant because dynamic soaring over the ocean demands precise control near waves and changing wind conditions. The test showed that the aircraft can operate autonomously in a challenging environment close to the sea.

The next major milestone for Alteon is moving from autonomous low-altitude flight to actual energy-neutral dynamic soaring. That means the aircraft would rely on wind shear alone for propulsion during a sustained portion of the flight. Sanghvi has characterized this as the key proof point for the company's technology.

Experts see promise and difficult challenges

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. He stressed, however, that the harder challenge will be proving that the aircraft can reliably extract enough energy from real-world winds to stay aloft for extended periods.

Bousquet noted that flying low enough to harvest energy is particularly difficult. The aircraft must contend with turbulence, waves, spray, rain, and changing light conditions while continuously sensing and reacting to a moving ocean surface. A small error in height or attitude could cause a crash into the water. The control systems needed for this are far more demanding than those used in most standard drone operations.

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

Swaminathan also pointed out that large-scale wind conditions may be predictable, but local wind shear and turbulence can vary substantially across short distances and short timeframes. That variability could complicate an aircraft's ability to continuously extract energy from the wind. Some of those challenges may only emerge during real-world flight testing, which is why Alteon's rapid prototyping approach could be valuable.

Investor conviction and founder story

Lachy Groom acknowledged the technical risk behind his investment. He said ambitious problems are always going to come with risks, and for him it came down to believing that Sanghvi and the Alteon team are the ones to figure them out.

Sanghvi began working on what would become Alteon immediately after high school in 2023. Rather than starting with theory, he learned to build aircraft by making and crashing radio-controlled models. Those hands-on lessons helped him develop early prototypes and understand how small aircraft behave in real conditions. He formally founded Alteon in 2025.

Alteon received early backing from Emergent Ventures and 1517 before the current round led by Groom. The pre-seed funding will support engineering work, test campaigns, and the development of aircraft that can carry out longer endurance missions.

The startup now has a team of 20 people in Bengaluru and operates from a 10,000-square-foot facility. It is building four to five aircraft each week for testing and has conducted more than 200 test flights in the past 30 days. That pace reflects the company's belief that controlled, repeated flight tests will be essential to solving the engineering challenge of dynamic soaring at scale.

Source:TechCrunch News