Pilot Union Opposes FAA Approval of Drone Cloud Seeding

Rainmaker Technology's Drone Cloud-Seeding Plan Faces Scrutiny

Rainmaker Technology is encountering opposition from the airline pilots union regarding its proposal to utilize small drones for the deployment of cloud-seeding flares. The Air Line Pilots Association (ALPA) has formally requested the Federal Aviation Administration (FAA) to potentially deny the startup’s application unless more stringent safety protocols are implemented.

FAA Decision to Shape Future Regulations

The FAA’s forthcoming decision will be pivotal in establishing how the agency approaches weather modification activities conducted via unmanned aerial systems. The viability of Rainmaker’s drone-based strategy is currently dependent on this regulatory outcome.

ALPA Raises Safety Concerns

ALPA communicated to the FAA that Rainmaker’s submission “does not demonstrate an equivalent level of safety” and presents “an extreme safety risk.” The union believes the current proposal is inadequate in ensuring safe operations.

Rainmaker Defends its Safety Measures

Augustus Doricko, Rainmaker’s CEO, asserted that the union’s criticisms are solely based on publicly available information. He stated that the company has submitted comprehensive safety data and risk mitigation strategies to the FAA in non-public documents.

Exemption Request and FAA Review

Rainmaker is seeking an exemption to regulations that prohibit small drones from transporting hazardous materials. The petition was filed in July, and the FAA is still deliberating. Currently, the agency has requested additional information, specifically regarding operational details and safety procedures.

Proposed Drone Operations and Altitude

Rainmaker’s plan involves utilizing two types of flares – a “burn-in-place” variety and an ejectable type – on its Elijah quadcopter to release particles that encourage precipitation. The Elijah drone has a maximum operational altitude of 15,000 feet above sea level, placing it within controlled airspace frequently used by commercial airliners. Drone flights within this airspace require authorization from Air Traffic Control.

Airspace Considerations

The petition indicates Rainmaker intends to operate primarily in Class G (uncontrolled) airspace, unless specific authorization is granted for other areas. While the filing lacks clarity regarding flight locations and altitudes, Doricko clarified that all flights will be confined to a maximum altitude of 15,000 feet MSL and will occur in airspace deemed safe by aviation authorities, addressing concerns about altitude and coordination.

Objections to Flares and Environmental Impact

The union also voiced concerns regarding the flares themselves, citing potential risks from foreign object debris and fire hazards. ALPA highlighted the absence of trajectory modeling for the ejectable casings and an analysis of the environmental consequences of the chemical agents used.

Addressing Environmental Concerns

Doricko countered these objections, stating that the materials used in cloud seeding have been studied for over 70 years by agencies like the EPA and state natural resource departments, with no adverse effects identified.

Rainmaker Seeks Collaboration

Sam Kim, Rainmaker’s aviation regulatory manager, expressed respect for the pilot’s union and a desire to “continue to strengthen our relationship.” He suggested the objection stems from a “lack of understanding” regarding the purpose of the exemption request.

Research Focus and Limited Operations

Kim emphasized that the use of flares is limited to research purposes within a controlled flying environment and is not representative of the company’s broader operational activities.

Material Comparison

Doricko pointed out that a typical Rainmaker operation disperses only 50-100 grams of silver iodide, significantly less than the kilograms of uncombusted volatile organics, sulfur oxides, and soot released by a single hour of commercial aircraft flight.

Focus on Aerosol Dispersion System

Rainmaker is actively developing a proprietary aerosol dispersion system to replace flares, exclusively emitting silver iodide. Doricko believes ALPA’s objection demonstrates a limited understanding of the company’s comprehensive operational concept and the extensive risk mitigations detailed in the non-public documents under FAA review.

Flight Operations and Safety Protocols

Regarding airspace coordination, Rainmaker’s operations involve broadcasting signals, intentional coordination with local Air Traffic Control, certified pilots, and a collision avoidance system incorporating both electronic and physical observers.

Rural Operations and Landowner Agreements

Rainmaker plans to conduct flights over rural areas and properties owned by private landlords with whom the company has established working relationships.

Existing Cloud-Seeding Practices

Cloud-seeding is already a common practice, particularly in the western U.S., utilizing crewed airplanes coordinated with state agencies. Ski resorts employ these operations to maintain snow cover, while irrigation and water districts use them to increase snowpack during winter months, replenishing reservoirs during the spring thaw.

Historical Context of Cloud Seeding

The practice of cloud seeding originated in the 1950s. Scientists discovered that introducing small particles into certain clouds could induce precipitation. Silver iodide is commonly used due to its similarity to ice crystal structures.

The Science Behind Precipitation Induction

When silver iodide particles collide with super-cooled water droplets, they trigger rapid freezing because the water is already below its freezing point. The resulting ice crystals grow quickly under favorable conditions, exceeding the growth rate of liquid water droplets and persisting longer before falling as precipitation.

Potential Benefits of Drone-Based Cloud Seeding

Rainmaker’s approach – utilizing drones instead of piloted aircraft – may offer enhanced safety in the long run. The company highlights tightly controlled flight profiles, remote pilot oversight, trained crews, rural operation locations, and additional safety measures.

FAA Decision and Future Implications

The next step depends on the FAA’s assessment of these safety mitigations. Regardless of the outcome, the agency’s response will likely establish a precedent for future cloud-seeding initiatives.

9/13/2025: This story has been updated to include comments from Augustus Doricko, founder and CEO of Rainmaker, and Sam Kim, Rainmaker’s aviation regulatory manager.