Swedish Innovations Lead the Way in Quieter Drone Technology

Swedish companies and research institutions are making significant advances in reducing drone noise, addressing a critical barrier to wider drone acceptance in various applications. The Swedish Defense Research Agency (FOI) is testing the unmanned underwater vehicle Luuv to enhance mine and submarine detection while minimizing acoustic signatures. Similarly, Dolprop Industries has developed Njord, an underwater drone propelled by a fin instead of a traditional propeller, giving it a low acoustic profile confirmed by the Swedish Defense Materiel Administration (FMV).

SAAB’s AUV62-MR minelayer drone employs a pumpjet propulsion system, which produces some noise; FMV placed a purchase order for these drones in December 2024. Marine Jet Power in Uppsala supplies low-noise waterjet systems designed to reduce acoustic and magnetic signatures for unmanned surface vehicles. Meanwhile, Bitcraze is pushing quieter micro-drone technology with its Crazyflie 2.1 Brushless model, supported by a Vinnova grant of 317,289 SEK to develop more efficient propellers reducing noise further.

Beyond Sweden, noise pollution from drones is a widespread challenge. In the U.S., the FAA regulates drone traffic but has drawn criticism for noise disturbances. Companies like Greenjets in London are developing propulsion systems that reduce drone noise by two-thirds by enclosing propellers and lowering rotational speeds, while U.S.-based Sharrow Engineering creates quieter propellers with unique twisted blade designs. Major players such as Amazon and Wing are also actively innovating to lower drone noise, with Amazon's latest propellers nearly 50% quieter than before and Wing optimizing flight paths to minimize repeated neighborhood overflights.

Experts emphasize that quieter drones could revolutionize applications in policing, security, and military operations, where stealthy unmanned vehicles offer clear advantages. These technological strides demonstrate a concerted effort globally, with Sweden playing a pivotal role in advancing quieter drone technologies for underwater and aerial platforms.