In the realm of maritime defence, the battle against Unmanned Aerial Vehicles (UAVs) or drones is an evolving challenge. This article, penned by Mr. Hasan Özyurt, delves into the intricacies of Anti-Drone Warfare (ADW) at sea, specifically focusing on the critical link between sensors and effectors. The author, a seasoned Rear Admiral, presents a compelling case for the importance of forward deployment and tiered overlap in ADW, highlighting the need for a comprehensive kill chain to counter the Tier 2 OWA drone threat.
One of the key insights is the detection challenge. The author argues that the low radar cross-section (RCS) of Tier 2 OWA drones, as low as 0.1 m², makes them virtually invisible to legacy air search radars. This is where compact Active Electronically Scanned Array (AESA) radar steps in. AESA radar, purpose-designed for counter-UAS missions, can detect and track targets with an RCS as low as 0.01 m² within the size, weight, and power (SWaP) constraints of small-to-medium Unmanned Surface Vessels (USVs). This technology forms the foundation of Tier 2 ADW detection, providing 360° coverage and multi-target tracking capabilities.
The discussion then shifts to identification and fire control, where the Electro-Optic System (EOS) plays a pivotal role. The author emphasizes the need for a multi-spectral EOS architecture, combining daylight, thermal, and SWIR channels, to achieve positive identification of targets at ranges of 5-10 km under various maritime conditions. This is crucial for maintaining reliability and accuracy in the face of sea-state-induced motion and changing environmental conditions.
When it comes to effectors, the author presents a nuanced analysis. Advanced surface-to-air missiles, while offering high kill probabilities, are economically unsustainable against mass campaigns and are not suitable for small unmanned platforms. Gun-based systems, despite their cost-effectiveness, face physical limitations in terms of range and weight. Electronic warfare, though effective against Tier 1 drones, is largely ineffective against Tier 2 OWA drones with terminal autonomy. Directed energy weapons, though promising, are still in the early stages of development and face challenges in terms of power demand and atmospheric effects.
The optimal effector choice, according to the author, is precision-guided light missiles in the SAL and IR/IIR categories. These missiles offer high kill probability, fast reaction times, and proven USV compatibility. Their roles are complementary, with SAL missiles providing precision hit-to-kill engagement and IR/IIR missiles offering true fire-and-forget autonomy. This pairing addresses the tactical gaps of either system alone, making it the most economically sustainable, operationally mature, and proven solution for small unmanned platforms.
In conclusion, the author emphasizes that the success of ADW at sea hinges on matching sensors and effectors to the physical and economic realities of the Tier 2 OWA drone threat. This requires a deep understanding of the threat's characteristics and the capabilities of available technologies. By doing so, maritime defence architectures can be designed to effectively close the kill chain and prevent the 'leaker' scenario, where a single drone can have devastating consequences for critical infrastructure or assets.
