Nanjing Airfly Electronic Technology Co., Ltd.

Tethered UAV Firefighting Solution: DJI FC300 + 42 kW Ground Power System How Kitefly Tethered's high-power tethered drone system breaks the altitude, endurance, and payload limits that have long constrained aerial firefighting, high-rise suppression, wildfire monitoring, and hazmat emergency response.   Overview: Redefining the Aerial Firefighting Market As urban high-rise fires, wildland-urban interface incidents, and chemical plant emergencies become increasingly common worldwide, the limitations of conventional firefighting equipment are being exposed. Aerial ladder trucks top out at 50–100 meters. Battery-powered drones provide only 20–40 minutes of flight time. Standard UAV platforms simply cannot carry the payload needed for suppression systems, communication relays, or heavy rescue equipment. The integration of the DJI FC300 heavy-lift UAV platform with Kitefly Tethered's 42 kW ground power system delivers a purpose-built solution that addresses all three constraints simultaneously — providing unlimited flight endurance, 150 kg payload capacity, and the ability to operate continuously above 150 meters. Kitefly Tethered (Nanjing Weize Chuangli Electronic Technology Co., Ltd.) is a nationally certified high-tech enterprise founded in 2018 and headquartered in Nanjing, China. With over a decade of tethered UAV power system development, Kitefly Tethered is one of China's earliest and most experienced tethered UAV power solution providers, with more than 30 custom tethered power configurations delivered globally. The company serves global markets across five core verticals: electric tethering, water tethering, wind turbine inspection, aerial display systems (FlyScreen), and heavy-load firefighting. Contact: susy@tetheredsystem.com  |  www.tetheredsystem.com   The Three Ceilings Blocking Modern Aerial Firefighting Emergency responders worldwide face three compounding limitations when deploying aerial assets in active fire scenarios. The FC300 tethered system is engineered specifically to break each one: Challenge Conventional Equipment DJI FC300 + Kitefly Tethered Altitude Ceiling 50–100 m (aerial ladders & platforms) 150 m+ continuous operation Flight Endurance 20–40 min per battery cycle 8+ hours continuous hover (24/7 capable) Payload Capacity Light drones: 5–10 kg only Up to 150 kg — suppression, delivery, comms Core Capabilities: What the FC300 Tethered System Delivers 1. Unlimited Flight Endurance — The Aerial Command Post The SG50 ground power box converts 380 V AC grid power to high-voltage DC and delivers it continuously through a 150–220 m tethered cable to the FC300 via the VF24 or WF36 onboard power module. This eliminates battery dependency entirely. ▸ 8+ hours of continuous hover — suitable for extended incident command and multi-phase firefighting operations ▸ 24/7 capable power delivery — ground power can be sourced from the grid, generator, or temporary power supply ▸ Full-scene aerial reconnaissance: real-time thermal imaging, wide-area surveillance, and night illumination with zero battery intervention ▸ Communications relay and incident command window — maintains an uninterrupted aerial communications node above the fire perimeter 2. Heavy-Lift Aerial Delivery — Opening the Last-Mile Supply Route The DJI FC300 platform supports a maximum payload of 150 kg across two operating modes: cargo container delivery and sling-load operations. This transforms the tethered drone from a sensor platform into an active logistics and suppression asset. Deliverable payloads include: ▸ Rescue equipment — breathing apparatus, rescue rope, forced-entry tools ▸ Emergency supplies — medication, drinking water, satellite communication devices ▸ Suppression payloads — firefighting grenades, dry powder canisters, compact water cannons In terrain inaccessible to ground vehicles — mountain valleys, collapsed structures, isolated islands — the FC300 provides minute-level precision aerial delivery to frontline responders. 3. High-Altitude Suppression — Breaking the High-Rise Firefighting Barrier Paired with an integrated tethered water-and-power pipeline, the FC300 system addresses the critical gap above 100 meters where conventional aerial ladder trucks and high-reach water cannons cannot reach. ▸ 150 m+ altitude suppression: precise application of water-based agents and foam suppressants on upper-floor high-rise fires ▸ Multi-axis attack coordination: top-down aerial suppression combined with ground-level operations to cut off fire spread ▸ Window breach and suppression: integrated breach-and-suppress capability to rapidly open rescue corridors   Technical Specifications Ground Power Unit — SG50 Tethered Power Box The SG50 is the ground station of the FC300 tethered firefighting system. It converts 380 V AC grid power to 1,000 V DC or 1,400 V DC and delivers it via a high-voltage tether cable to the onboard power module aboard the FC300. Peak output of 40 kW supports the full range of onboard payloads simultaneously.   Parameter Specification Product Model SG50 Input Voltage 380 V AC Output Voltage 1,000 V DC  /  1,400 V DC Peak Power 40 kW MAX Cable Length 150 – 220 m Power Supply Box Weight 49.3 kg ± 1 kg Cable Box Weight 32.9 kg ± 1 kg Power Supply Box Dimensions 498 × 472 × 440 mm Cable Box Dimensions 498 × 471 × 440 mm   Onboard Power Module — VF24 (24 kW Configuration) The VF24 regulated onboard power module steps down the high-voltage tether input to the precise DC voltage required by the FC300's propulsion system and attached payloads. Compatible with 12S to 28S battery-equivalent voltage configurations. Parameter Specification Product Model VF24  (Regulated Series) Input Voltage 800 – 1,000 V DC Output Voltage 50 / 60 / 73 / 100 V DC  (12S / 14S / 18S / 24S / 28S) Peak Power 24 kW MAX Weight 9 kg ± 100 g Dimensions 370 × 223 × 127 mm Onboard Power Module — WF36 (42 kW Configuration) The WF36 is the high-power onboard module for maximum-payload operations, supporting up to 42 kW peak output. This is the recommended module for suppression system integration and full 150 kg payload operations. Parameter Specification Product Model WF36  (Regulated Series) Input Voltage 1,200 – 1,400 V DC Output Voltage 40 – 60 V DC  (12S / 14S / 18S / 24S / 28S) Peak Power 42 kW MAX Weight 11 kg ± 100 g Dimensions 326 × 280 × 143 mm   Application Scenarios Urban High-Rise & Super-Tall Building Firefighting The FC300 tethered system enables rapid deployment within 3 minutes, ascending to operational altitude as fire suppression vehicles arrive on scene. Above 100 m, it provides continuous suppression, aerial search-and-rescue coordination, and a communications relay that reaches through structural interference that ground-level systems cannot penetrate. For fire incidents above the 30th floor, this system represents the only currently available persistent aerial suppression platform. Wildland & Forest Fire Operations Extended aerial patrol of fire perimeters — day and night. Infrared fire-point detection and hotspot mapping. Real-time fire behavior analysis for frontline command. Nighttime high-intensity lighting for ground crew safety. Precision aerial delivery of water and suppression agents to forward positions inaccessible by road. The tethered power system enables this capability to run continuously through multi-day fire incidents without crew intervention for battery management. Chemical Plant & Hazardous Materials Emergency Response In chemical plant incidents and hazardous materials scenarios, human proximity to the incident zone significantly increases casualty risk. The FC300 tethered system provides a persistent standoff reconnaissance and monitoring capability — thermal imaging through smoke, toxic gas detection payload integration, continuous communications relay for multi-agency coordination, and supply delivery to responders in protective equipment who cannot quickly evacuate for resupply. Operational & Commercial Value ▸ 3-minute rapid deployment — co-deploys with the first response vehicles on scene ▸ System consolidation — one integrated platform replaces multiple single-purpose aerial assets, reducing procurement and maintenance overhead ▸ Platform integration — compatible with DJI FlightHub 2 / Skydio for multi-aircraft coordinated operations and single-screen command ▸ Scalable deployment model — adaptable to smart city emergency response networks, airport perimeter security, and regional mutual-aid firefighting consortia Why Kitefly Tethered for Firefighting UAV Power Systems Tethered drone power is a specialized engineering domain. The power conversion chain — from 380 V AC grid input through high-voltage tether transmission to precise low-voltage DC output matching propulsion bus requirements — involves thermal management, voltage stability under dynamic load, and cable mechanics that general-purpose power electronics suppliers are not designed to address. Kitefly Tethered brings: ✓ 10+ years of focused tethered UAV power system development ✓ 30+ custom tethered power configurations delivered across electric, water, and heavy-lift applications ✓ One of China's earliest tethered UAV solution providers — field-proven across global markets ✓ Full power chain coverage: ground boxes (AC to HVDC), onboard modules (HVDC to drone bus voltage), and accessories ✓ Integrated accessory ecosystem: tethered lighting, firefighting modules, wash systems, relay systems, screen systems, and hangar systems   Request a Consultation or Technical Proposal Whether you are evaluating tethered UAV firefighting systems for a municipal emergency services procurement, an airport authority deployment, or a regional wildfire response program, Kitefly Tethered's engineering team can provide technical configuration guidance, custom integration support, and formal proposal documentation.   Email: susy@tetheredsystem.com Website: www.tetheredsystem.com   We welcome inquiries from system integrators, emergency services agencies, government procurement offices, and international distribution partners.

Why Choose a Tethered Drone System? As drone technology continues to evolve, more industries are looking for solutions that allow long-duration aerial operations without the limitations of batteries. A tethered drone system provides a reliable way to keep drones in the air for extended periods by supplying continuous power from the ground. This technology is increasingly used in applications such as security surveillance, emergency communication, aerial lighting, and high-rise building cleaning. What Is a Tethered Drone System? A tethered drone system is a UAV solution that receives power through a cable connected to a ground power station. Instead of relying solely on onboard batteries, the drone is powered through a high-voltage tether cable that delivers electricity from the ground while transmitting data through fiber optics or communication lines. A typical tethered drone system includes: l Ground power station l Tether cable (power + communication) l Airborne power module l Tether management system or winch l UAV platform This configuration allows the drone to operate continuously while maintaining stable communication with the ground. How Does a Tethered Drone Work? A tethered drone works by transferring electrical power from a ground power supply unit through a lightweight tether cable to the drone. The process usually follows these steps: 1. The ground power station converts grid or generator power into high-voltage DC output. 2. The power is transmitted through the tether cable to reduce current and minimize cable weight. 3. An airborne power module on the drone converts the high voltage into the voltage required by the UAV. 4. The drone can then operate continuously without relying on battery capacity. In many systems, the tether cable also integrates fiber optic communication, ensuring stable data transmission and control. Key Advantages of Tethered Drone Systems 1. Unlimited Flight Endurance One of the biggest limitations of conventional drones is battery life, which usually ranges between 20 to 40 minutes. A tethered drone system can remain airborne for several hours or even days, as long as ground power is available. This makes tethered systems ideal for missions that require persistent aerial presence. 2. Stable and Secure Power Supply Because the drone receives power directly from the ground, operators no longer need to frequently land the drone for battery replacement. This significantly improves operational efficiency and reduces mission interruptions. 3. Reliable Data Transmission Many tethered drone systems integrate fiber optic communication inside the tether cable, providing a stable and interference-free communication link. This is especially important in environments where radio signals may be restricted or unstable. 4. Enhanced Operational Safety The tether cable physically connects the drone to the ground station, which can provide an additional layer of safety and control. In many regulated environments, tethered drones may also benefit from simplified regulatory approval, since their operational area is restricted. Common Applications of Tethered Drones Tethered drone technology is widely used across multiple industries where continuous aerial capability is required. Typical applications include: Security and Surveillance Providing long-duration aerial monitoring for events, borders, critical infrastructure, and urban security. Emergency Communication Acting as an aerial relay station to quickly restore communication networks during disasters. High-Rise Building Cleaning Supporting drone-based facade cleaning systems that require stable power and water supply. Aerial Lighting Delivering high-power lighting for night operations, construction sites, and search-and-rescue missions. Event Broadcasting Providing stable aerial camera platforms for live broadcasting and event coverage. Tethered Drone vs Battery Drone Feature Battery Drone Tethered Drone Flight Time 20–40 minutes Continuous operation Power Source Onboard battery Ground power supply Communication Wireless Cable + optional fiber Operational Stability Limited by battery Long-duration missions Typical Applications Photography, inspection Surveillance, lighting, communication Is a Tethered Drone Right for Your Application? A tethered drone system is best suited for missions that require: l Continuous aerial coverage l High power payloads l Stable communication l Long-duration operations If your application requires persistent aerial presence, a tethered drone system may provide significant operational advantages over traditional battery-powered UAVs. About Kitefly Tethered Kitefly Tethered specializes in tethered drone power supply systems, including ground power stations, airborne power modules, tether cables, and integrated tethered UAV solutions. Our systems are designed for professional applications such as aerial cleaning, surveillance, emergency communication, and industrial inspection.   Learn more about our tethered drone solutions or contact our team for technical consultation.  

The Ultimate Guide to Tethered Drone Systems As drone technology continues to develop, one limitation still affects most UAV operations: limited battery life. Traditional drones usually fly for 20–40 minutes, which restricts their ability to perform long-duration missions such as surveillance, communication relay, or aerial lighting. A tethered drone system solves this challenge by supplying continuous power from the ground through a tether cable, allowing drones to remain airborne for extended periods. Today, tethered UAV systems are widely used in industries such as public safety, security monitoring, emergency communication, aerial lighting, and high-rise building cleaning. This guide explains how tethered drone systems work, their key advantages, and where they are commonly used. What Is a Tethered Drone System? A tethered drone system is a drone platform connected to a ground power source through a cable known as a tether. Instead of relying only on onboard batteries, the drone receives electrical power from the ground via the tether cable. This allows the UAV to operate for long durations without needing to land for battery replacement. A complete tethered drone system typically includes:   l Ground power station l Tether cable (power + optional communication) l Airborne power module l Tether management system or winch l UAV platform   The tether cable transmits electrical power while also maintaining a physical connection between the drone and the ground station. How Does a Tethered Drone Work? A tethered drone system works by transferring electrical power from the ground to the drone through a lightweight tether cable. The basic operating process includes:   1. Ground Power ConversionThe ground power station converts grid or generator power into high-voltage DC power suitable for long-distance transmission. 2. Power Transmission Through the Tether CableThe high-voltage electricity travels through the tether cable to reduce current and minimize cable weight. 3. Airborne Power ConversionAn airborne power module mounted on the drone converts the incoming voltage into the voltage required by the UAV and its payload. 4. Continuous Flight OperationSince power is constantly supplied from the ground, the drone can remain airborne for extended periods without relying on battery capacity.   Some tethered systems also integrate fiber optic communication within the tether cable, enabling stable and secure data transmission. Key Advantages of Tethered Drone Systems Continuous Flight Time The most important advantage of tethered drones is extended flight endurance. While battery-powered drones must frequently land to replace batteries, tethered drones can remain airborne for hours or even days as long as ground power is available. This makes them ideal for applications requiring persistent aerial presence. Reliable Power Supply Ground-based power eliminates the need for multiple batteries and reduces operational downtime. Operators can perform longer missions without interruptions caused by battery replacement. Stable Communication In many tethered systems, communication can be transmitted through fiber optic lines integrated into the tether cable. This ensures stable, high-bandwidth communication with minimal interference compared to wireless signals. Improved Safety and Control The physical tether connection provides an additional level of operational control.   In some scenarios, tethered drones may also simplify airspace compliance because their operational area is limited by the tether cable. Tethered Drone vs Battery-Powered Drone Feature Battery Drone Tethered Drone Flight Time 20–40 minutes Continuous operation Power Source Onboard batteries Ground power supply Communication Wireless Cable or fiber optic Mission Duration Limited Long-duration missions Typical Applications Photography, inspection Surveillance, lighting, communication Battery-powered drones are ideal for mobility and inspection tasks, while tethered drones are better suited for persistent aerial operations. Common Applications of Tethered Drone Systems   Security and Surveillance Tethered drones are widely used for continuous aerial monitoring at events, borders, critical infrastructure sites, and urban environments. They provide stable, elevated observation platforms that can remain in the air for long periods. Emergency Communication During natural disasters or large-scale emergencies, tethered drones can act as temporary communication relay stations, restoring network coverage when ground infrastructure is damaged. Aerial Lighting High-power lighting payloads mounted on tethered drones can illuminate large areas at night. This is commonly used for construction sites, emergency rescue, and night operations. High-Rise Building Cleaning Tethered drone systems are increasingly used in drone-based facade cleaning solutions, where stable power supply and continuous operation are required for high-rise buildings. Event Broadcasting and Monitoring Tethered drones provide stable aerial camera platforms for live events, broadcasting, and public safety monitoring. Why Tethered Drone Technology Is Growing The demand for persistent aerial capability continues to grow across industries. Compared with conventional drones, tethered UAV systems provide: l Longer operational time l Stable communication links l Reliable ground power supply l Greater operational efficiency   As drone applications expand in fields such as smart cities, public safety, and industrial services, tethered drone systems are becoming an important part of the UAV ecosystem. About Kitefly Tethered Kitefly Tethered focuses on the development of professional tethered drone power supply systems, including ground power stations, airborne power modules, tether cables, and integrated tethered UAV solutions. Our systems support applications such as:   l Aerial cleaning l Surveillance and security l Emergency communication l Industrial inspection l Aerial lighting   For more information about our tethered drone systems, please contact our team or explore our product page.   Tethered Drone FAQ   How long can a tethered drone fly? A tethered drone can remain airborne for extended periods, as it receives continuous power from the ground through a tether cable. In practice, the actual flight duration is mainly determined by the drone platform itself, including the durability of the motors, cooling performance, and overall system reliability during long operations. Unlike battery-powered drones that are limited to 20–40 minutes of flight time, tethered drones do not rely on onboard batteries for endurance. As long as ground power is available and the UAV platform can sustain long operation, the drone can continue flying. This makes tethered drones suitable for missions requiring long-duration aerial presence, such as surveillance, communication relay, and aerial lighting. How high can a tethered drone operate? The maximum altitude of a tethered drone mainly depends on the length and design of the tether cable as well as regulatory restrictions. Most commercial tethered drone systems typically operate at heights between 50 and 200 meters, depending on system configuration and application requirements. In many countries, aviation regulations may also limit drone altitude, which can affect the operational height of tethered UAV systems. What voltage is used in tethered drone systems? Tethered drone systems usually transmit high-voltage DC power through the tether cable. High voltage is used to reduce current and minimize energy loss in the cable while keeping the cable lightweight. Typical transmission voltages range from 400V to 1500V DC, depending on the system design and power requirements. An airborne power module installed on the drone then converts this voltage into the appropriate level required by the UAV and its payload. What industries use tethered UAV systems? Tethered drone systems are used in industries that require long-duration aerial operations. Common applications include: l Security and surveillance for events, cities, and critical infrastructure l Emergency communication during disasters or network outages l Aerial lighting for night construction or rescue operations