The systems are intended for use across air, maritime surface and subsea domains. L3Harris said they support special operations and conventional forces requiring secure command and control during missions in hostile or denied areas.
“The threat is no longer theoretical – it is shaping the battlefield in real time. We see adversaries aggressively jamming, disrupting and hijacking RF-controlled unmanned aerial systems at scale, exposing a critical vulnerability in modern drone operations,” said Dave Kornick, President, Intelligence and Cyber, L3Harris.
“Operational success now depends on resilient command-and-control architectures that can survive in the most contested electromagnetic environments. Our Drone Fiber-Optic Tethers (DFT) provide a secure, physical connection between operator and aircraft, ensuring uninterrupted control, mission assurance and battlefield survivability when electronic warfare conditions are at their worst,” Kornick added.
L3Harris said its Drone Fiber-Optic Tether systems are optimised for missions exceeding 25 kilometres and have been tested overseas against active electronic warfare systems. The company said the systems provide data transfer speeds 10 times faster than radio frequency alternatives while remaining lighter and smaller than competing tethered solutions.
The company said the systems provide secure, high-bandwidth communications that cannot be jammed, intercepted or disrupted. The National Defense Authorization Act-compliant systems are manufactured in Palm Bay, Florida.
L3Harris has developed two media converter systems to allow existing radio frequency-controlled drones to be converted rapidly to fiber-optic operation. The analogue fly-by-fiber system clips into NDAA-compliant controllers and integrates with UART-controlled RF drones, while the digital fly-by-fiber system provides low size, weight and power performance with latency of less than 70 milliseconds.
The company said its micro-diameter fiber-optic cable delivers data transfer rates more than 10,000 times greater than traditional copper systems. The technology is used in the L3Harris-built Improved Post-Launch Communications System for the U.S. Navy’s next-generation MK-48 Mod 8 torpedo.
L3Harris said multiple U.S. Navy and industry partners have selected the company as a fiber-optic tether provider for maritime and subsea applications. These include unmanned surface and underwater vehicle programmes.
The company said it is investing to scale production of American-made next-generation attritable drone technologies and components. L3Harris expanded its fleet of advanced fiber pack winders through 2025 and 2026, with further capacity growth underway to meet operational demand.
According to L3Harris, the investments are intended to strengthen the U.S. defence industrial base and reduce supply chain dependence. The company said the goal is to ensure warfighters have access to survivable fiber-optic solutions for contested electromagnetic environments.
L3Harris also supports integration of fiber-optic command-and-control systems onto existing small unmanned aerial system platforms. Its work includes 3D modelling, prototyping, electrical integration, software development and field flight testing.
The company said trained and certified drone pilots support its integration activities. L3Harris said the capability gives U.S. forces secure, high-bandwidth connections across air and sea domains as electronic warfare threats intensify.
