AN/AQS
AN/AQS-20
The U.S. Navy's standard for minehunting, the AN/AQS-20 is an advanced minehunting sonar system that has been designated as the minehunting sonar for the Littoral Combat Ship's mine countermeasure mission package.
The AN/AQS-20 incorporates four separate sonars in a compact, lightweight and hydro-dynamically stable towed body. It uses state-of-the-art imaging sonars, signal processing and computer algorithms to provide real-time, computer-aided detection and classification against the full spectrum of threat mines. The AN/AQS-20 automatically localizes mine-like objects and provides the operator with a visual image and a contact data list. All mission data is recorded for post-mission analysis.
The AN/AQS-20's computer processing power and advanced signal processing, coupled with its portability, reduces the amount of time required to search an area while significantly increasing search-rate agility. By reducing the size of the platform and the number of crew required to deploy the system, the AN/AQS-20 safely and efficiently consolidates expansive mine-sweeping operations that previously required a large warfare ship manned by more than 80 crew members.
This low-risk approach gives the fleet an organic mine countermeasures capability in the near term that meets all Navy requirements. The AN/AQS-20 towed body satisfies the requirements of three platforms through common hardware, software and interfaces; common integrated logistics support; and modular operational configurations. The AN/AQS-20 has been extensively tested and operated from unmanned, underwater vehicles such as the AN/WLD-1 and was the only minehunting sonar sensor developed, tested and certified for Remote Multi Mission Vehicle deployment. It is the most advanced and capable mine warfare sensor system, fully integrated with and effectively operated from the Littoral Combat Ship 2.
The combination of sidescan, forward-looking and gapfiller sonars enables the AN/AQS-20 to detect and classify mine-like objects from the seafloor to the near surface in a single pass. The system also has an electro-optics identification capability that delivers high-definition images of bottom mines using Streak Tube Imaging Laser technology. This provides the operator with both range and contrast data for post-mission analysis to aid in mine identification.
Four modes of operation are provided:
Single Pass Shallow Mode — Bottom and moored mine coverage in a single pass
Single Pass Deep Mode — Moored mine coverage in deep water
Volume Mine Mode — Volume mine coverage at four times the area search rate
Identification Mode — Bottom and moored mine coverage in a single pass plus optical imaging of bottom mines
These modes enable the AN/AQS-20 to give timely and accurate information on the location and position of mines to support neutralization by systems such as the Airborne Mine Neutralization System.
In January 2020 Raytheon delivered its 10th AN/AQS-20C minehunting sonar system to the U.S. Navy. The sonar-towed body was officially transferred to the Naval Surface Warfare Center, Panama City Division. The system – which is the program of record for the Navy's Littoral Combat Ship mine countermeasure mission package – is now fully qualified and will move toward initial operating capability.
The AN/AQS-20C comprises five distinct sonars, including a synthetic aperture sonar that provides the highest possible resolution for acoustic identification. The system detects, classifies, localizes, and identifies mines on the seabed, near-bottom moored mines, volume mines, and near-surface mines.
'AQS-20C is capable of enabling true single-pass, minehunting when paired with the Barracuda mine neutralizer,' said Wade Knudson, senior director of Raytheon's Undersea Warfare Systems business area. 'Delivery of the 10th towed body brings this critical autonomous technology one step closer to IOC.'
The AQS-20C system is platform agnostic and can be integrated onto various tow vehicles. It is a key element in single sortie detect-to-engage capability, which combines the search-detect-identify and neutralize elements of an MCM mission on a single platform. The program completed developmental testing in February 2019, and will undergo further integration on the MCM Unmanned Surface Vehicle in early 2020 and ultimately aboard the LCS.