“For AirForestry, which develops flying electric harvesting drones to thin trees and make the forest grow better, the project with Aero EDIH has been very valuable. We see the fact that our drones also have a low noise profile as an important piece of the puzzle for the future of gentle forestry”, says Mauritz Andersson, Co-founder & CTO, AirForestry.
Challenges
AirForestry is pioneering drone-based forestry operations with a heavy-lift UAS (Unmanned Aerial System) designed for harvesting applications. The aircraft, weighing approximately 400 kg, operates with six rotors and was tested both with a 60 kg load and without. Noise emissions during hover and load-handling phases represent a critical barrier to scaling these operations, particularly in forest areas near residential zones.
Compliance with emerging EASA (European Union Aviation Safety Agency) noise guidelines and community acceptance are essential for AirForestry’s business model, making accurate noise characterization and mitigation strategies a priority.
Solutions
Aero EDIH facilitated to measure and model noise from AirForestry’s harvest UAS. Field tests focused on hover conditions, with microphones positioned at approximately 8 meters height to capture representative sound levels. GPS data and rotor RPMs were logged to correlate acoustic signatures with operating parameters.
The measurements were processed to calculate A-weighted sound power levels and identify tonal components such as blade-passing frequency. Simulation tools were then used to create noise maps, enabling visualization of exposure patterns and supporting dialogue with stakeholders.
Results and Benefits
The project delivered detailed noise profiles for AirForestry’s UAS under different load conditions, providing actionable insights for operational planning. Analysis confirmed that hover phases dominate acoustic impact, with tonal rotor noise contributing to perceptibility. By translating these findings into noise maps, AirForestry can now evaluate site selection, adjust operating procedures, and communicate transparently with local communities.
These results also support AirForestry’s engagement with regulators and municipalities, demonstrating a commitment to responsible operations and paving the way for future certification. The methodology developed ensures repeatability and scalability, enabling AirForestry to apply the same approach to new platforms and missions.
Perceived Social and Economic Impact
By mitigating noise impacts, AirForestry strengthens its ability to deploy sustainable forestry solutions that reduce environmental footprint compared to traditional methods. The approach enhances public acceptance, supports regulatory compliance, and contributes to the modernization of forestry operations, creating economic and ecological benefits for rural regions.
Lessons learned
Perform noise measurements early in the development cycle to inform design and operational strategies. Use mapping tools to visualize exposure and guide decisions on pad placement and flight profiles. Engage stakeholders with clear, evidence-based communication.
Avoid prolonged hover near sensitive areas; even small changes in procedure can significantly reduce noise footprints. Do not assume that cruise phases are the primary concern—hover and load-handling dominate community exposure.
“Aero EDIH has during 2025 supported Air Forestry AB in a project performing noise measurements of drones, executed by Akustikdoktorn AB. Noise performance is becoming a decisive factor for the commercial and societal acceptance of drones and eVTOL systems, and a core enabler in the EU Drone Strategy 2.0. As new measurement and certification standards emerge from EASA and the FAA, manufacturers must be able to demonstrate not only compliance, but also a clear methodology for noise minimisation across all flight modes.
By combining field measurements with advanced acoustic modelling of lift, hover, transition, cruise, and descent, we are establishing representative source models that translate physics-based understanding into practical design and planning tools. This capability enables manufacturers to produce credible noise maps for real operational scenarios, support customers in impact assessments, and proactively adapt to forthcoming regulatory requirements.
Ultimately, systematic acoustic measurement and modelling are not just about compliance – they are a competitive advantage. They provide Swedish UAS manufacturers with a concrete foundation for quieter designs, smoother certification pathways, and sustainable deployment of drone-based services in urban and regional airspace.”, says Rasmus Lundqvist, Innovation lead, Aero EDIH.
