ECA Group demonstrated the capabilities of A-18M AUV in Toulon area in February 2018. Credit: ECA Group.
The autonomous underwater vehicle maintains a high degree of stability, which enables it to take high-resolution images of the detected objects. Credit: ECA Group.
The data collected by the AUV is processed using the on-board processing facility and is then sent to the command centre for further analysis. Credit: ECA Group.

A-18M is a new autonomous underwater vehicle (AUV) designed and developed by ECA Group. It is the only military variant in the A-18 AUV family of vehicles. The AUV made its first public appearance in February 2018.

The mid-sized AUV can perform a range of mine countermeasure (MCM) missions, including identification and classification of conventional underwater mines and mine-like targets.

The vehicle complies with the standardisation agreement (STANAG) 1364 of Nato. It can be deployed from unmanned surface platforms such as ECA Group’s Inspector Mk2  MCM unmanned surface vessel (USV).

A-18M AUV design and features

Modular design techniques were employed in the development of the A-18M AUV. The vehicle integrates a compact structure and can be deployed in MCM missions involving the neutralisation or disposal of underwater mines.

It withstands harsh environmental conditions and offers greater stability when encountering heavy turbulence from waves.

The high degree of stability enables the vehicle to capture high-resolution images. The information obtained by the platform is processed in the command centre. A USV will act as a bridge between the command centre and the AUV.

The lightweight and compact design of the vehicle allows the operators to deploy it from small platforms such as USVs, frigates and corvettes. The vehicle can operate at a maximum depth of 300m, which can be altered based on the operational requirements.

The AUV has a length of 3.8m and diameter of 0.465m, however, its length can be extended based on payload and modules. The underwater vehicle weighs 370kg and can be transported by air for distant missions.

The underwater vehicle can be incorporated into a larger network of unmanned systems. It can also form part of ECA Group’s Unmanned Maritime Integrated System (UMIS) suite.

Payloads and sensors of A-18M AUV

The design of A-18M allows it to incorporate a wide range of payloads based on mission requirements. The vehicle has a large payload capacity and carries an interferometric synthetic aperture sonar (SAS) to detect and classify mines with high accuracy. It offers a maximum swath of 2 x 265m and along-track resolution between 3cm and 220m.

Other major payloads on the AUV include video equipment, a forward-looking Sonar, CTD instrument, acoustic Doppler current profiler (ADCP) and equipment to measure turbidity in water.

The A-18M AUV can be optionally equipped with ultra-short baseline systems (USBL) or long baseline systems (LBL) type tracking systems. Other options include the launch and recovery system (LARS) for a rigid-hulled inflatable boat (RHIB), surface ship integration, and containerised unit.

Navigation and communication

Navigation systems installed on the vessel include an inertial navigation system (INS), military global navigation satellite system (GNSS), global positioning system (GPS) and Doppler Velocity Log (DVL).

The A-18M AUV features an inbuilt Wi-Fi facility, ethernet, acoustic methods and satellite communications to maintain communications with the command centre.

Safety is ensured by the on-board safety equipment, such as emergency pinger, fault or leak detection, and strobe light, which alert the personnel in the command centre in case of emergencies during the mission.

A-18M AUV propulsion and performance

The AUV is powered by a 10.6kWh energy unit, which allows the vehicle to attain a maximum speed of up to 6k. The nominal speed of the vehicle is 3/4k, while the maximum area coverage rate is more than 2km²/h.

The A-18M AUV offers a maximum endurance of up to 24 hours.