Drones Take Aim at Cloud Seeding: A New Approach Faces Scrutiny
A burgeoning company, Rainmaker, is seeking to revolutionize cloud seeding – a decades-old practice of attempting to induce precipitation – by utilizing unmanned aerial systems (drones) instead of customary crewed aircraft. However, their request for an exemption to operate these drones has sparked opposition from the Air Line Pilots Association (ALPA), raising questions about safety and coordination.
cloud seeding itself isn’t new. Since the 1950s, the technique has been employed, particularly in the western United States, by ski resorts seeking to bolster snowpack and irrigation districts aiming to replenish reservoirs. the process involves dispersing small particles, typically silver iodide, into clouds to encourage ice crystal formation and, ultimately, precipitation. Silver iodide is favored because its structure closely resembles that of natural ice crystals, triggering rapid freezing in super-cooled water droplets. This accelerated growth allows ice crystals to form and fall as precipitation more effectively than liquid water droplets.
Rainmaker’s innovation lies in automating this process with drones. The company emphasizes that their current drone flights utilizing flares are strictly for research within a controlled habitat, separate from their ongoing operational cloud seeding. They are actively developing a proprietary aerosol dispersion system designed to replace flares and exclusively emit silver iodide.
“Our use of flares in unmanned systems is solely for research purposes in a controlled flying environment and is not a part of our larger ongoing operations,” explained Sam Kim, Rainmaker’s aviation regulatory manager.
The company defends the environmental safety of their operations, pointing to over 70 years of study by the EPA and state departments of natural resources which have found no adverse effects from cloud seeding. Augustus Doricko, Rainmaker’s founder and CEO, highlighted the minimal material dispersed during a typical operation – 50-100 grams of silver iodide, and even less during flare flights – compared to the kilograms of pollutants released by commercial aircraft.
Though, ALPA has voiced concerns regarding coordination with aviation authorities and airspace management. Rainmaker counters that their flights are meticulously planned, involving signal broadcasting, direct coordination with Air Traffic Control, certified pilots overseeing operations remotely, and a comprehensive collision avoidance system utilizing both electronic and physical observers. Flights are planned over rural areas and private land, where Rainmaker has established relationships with landowners.
Doricko argues that ALPA’s objections stem from a misunderstanding of Rainmaker’s comprehensive safety protocols,detailed in non-public documentation currently under review by the Federal Aviation Governance (FAA). He believes the drone-based approach could ultimately be safer than traditional methods, citing tightly bounded flight profiles, remote oversight, and additional safety checks.
The FAA’s decision on Rainmaker’s exemption request will be pivotal. It will not only determine the fate of this specific project but also likely establish a precedent for future innovative approaches to cloud seeding and the integration of unmanned systems into atmospheric research.
(Updated 9/13/2025 to include comments from Augustus Doricko and Sam Kim of rainmaker.)