New Delhi, Sept. 1 -- Bengaluru-based deep-tech aerospace startup Alteon has raised $2.5 million in pre-seed funding led by Lachy Groom, with participation from Together Fund, as it works on autonomous aircraft designed to remain airborne for months without landing.

The funding follows an offshore flight test in which Alteon's aircraft autonomously completed multiple consecutive loops at less than one metre above the open ocean. The company said the test cleared a key engineering hurdle for its longer-term goal of developing aircraft that can use wind energy to sustain flight without propulsion.

Alteon is developing autonomous dynamic soaring aircraft that extract energy from wind gradients, similar to the way albatrosses remain airborn...