The LH90 is an advanced tethered drone system designed for persistent aerial surveillance and communication applications. Unlike conventional drones limited by battery life, this platform utilizes a secure tether connection to provide continuous power and high-speed data transmission, enabling extended mission durations without interruptions.At the core of the LH90's design is its ruggedized carbon fiber airframe, engineered to withstand harsh environmental conditions while maintaining optimal flight stability. The system features a proprietary tether management mechanism that automatically adjusts cable tension during flight operations, ensuring minimal interference with the drone's maneuverability. With a maximum tether length of 90 meters, the platform offers substantial operational altitude while maintaining a secure physical connection to the ground station.The propulsion system incorporates six brushless motors configured in a hexacopter arrangement, delivering redundant thrust capability that enhances operational safety. This multirotor configuration allows the LH90 to maintain position with centimeter-level accuracy even in challenging wind conditions up to 15 m/s. The integrated flight controller utilizes real-time kinematic positioning combined with advanced stabilization algorithms to compensate for tether-induced disturbances.For mission flexibility, the platform supports modular payload integration through its standardized gimbal interface. Typical configurations include high-resolution EO/IR cameras with 30x optical zoom capabilities, multispectral sensors for agricultural monitoring, or specialized communication relays. The tethered connection enables virtually unlimited data throughput, allowing transmission of uncompressed 4K video streams and sensor data with near-zero latency.The ground power supply unit features intelligent power management that dynamically adjusts voltage delivery through the tether, compensating for cable resistance over extended lengths. This system includes automatic fault detection that initiates controlled recovery procedures in case of power fluctuations or tether integrity issues. Operational control can be conducted either through a dedicated ground control station or integrated with existing command systems via API interfaces.Security features include encrypted data links through the tether, frequency-agile RF systems to avoid interference, and optional anti-jamming capabilities for contested environments. The entire system can be deployed within 10 minutes by a two-person crew and operates with minimal acoustic signature compared to generator-powered alternatives.With its combination of endurance, stability, and payload capacity, the LH90 tethered drone system represents a significant advancement in persistent aerial platform technology, suitable for border security, critical infrastructure protection, emergency response, and other applications requiring uninterrupted aerial awareness. The system's design prioritizes reliability and ease of operation while eliminating the logistical challenges associated with battery changes or refueling during extended missions.