The Intelligence Advanced Research Projects Activity (IARPA) is kicking off an initiative to develop noiseless next-gen drones.
Research for the project will be conducted under the auspices of IARPA's Great Horned Owl Program, and is likely to build on previous work done by NASA in the context of attempting to design a quiet aircraft.
As Wired's Lena Groeger points out, the only drones currently registering under the decibel limit are small, battery-run systems which lack sufficient power to properly execute lengthy missions.
As such, IARPA wants an improved, longer-lasting aircraft capable of helping the DoD with the smart and stealth collection of actionable intelligence.
To be sure, the Pentagon is understandably concerned that "the acoustic signature of [current] UAV's alerts the adversary to the [aircraft's] presence and can interfere with its mission."
To create a quiet drone, the agency envisions an electrically powered hybrid vehicle equipped with ducted propellers systems to dampen mechanical noises. Advanced flight control systems would also act to reduce noise generated by airflow around the craft.