The US Navy has briefed the media on the (alleged) first use of an Autonomous Underwater Vehicle (AUV) for a military operation by a US submarine (see article below). "AUV" is a subset of the more common term Unmanned Underwater Vehicle (UUV). The US Navy then gives no details of the AUVs actual use in the body of water in question - the Mediterranean Sea.
"No details" always tempts me to fill in the blanks. So I looked up the details of the AUV in question, known as the REMUS 600, on the website of the developer-builder, Kongsberg-Hydroid. Note that Kongsberg-Hydroid is a Norwegian firm - not US.
Results gleaned are that Kongsberg-Hydroid AUVs (“drones”) are modular and may be fitted with a large number of different types of sensors and have been used to aid in hydrographic surveys, harbor security operations, debris field mapping, scientific sampling and mapping. Kongsberg-Hydroid AUVs have been used in as many basic and applied research programs funded by the US Office of Naval Research (ONR), the US Defense Advanced Research Projects Agency (DARPA) and the UK Ministry of Defense.
So to what sensitive part of the Mediterranean Sea might the USS North Dakota nuclear attack submarine (SSN) send its REMUS 600 AUV on a sensitive mission? The Russian Naval Base of Tartus in Syria may qualify as most sensitive. Tartus is also a major signals (intercept) intelligence base. The AUV might plausibly gather intelligence on the appoaches to Tartus's harbour. This may include hydrographic conditions (eg. water temperature, currents and sea floor mapping). The AUV may also gather the sonar and other sensor signatures of Russian warships entering or leaving Tartus harbour. Any Russian Tartus harbor security measures would be of interest including Russian sea floor sensors.
Specifications of the Kongsberg-Hydroid REMUS 600 - Autonomous underwater vehicle (AUV)
- Vehicle diameter: 32.4 cm (12.75 in)
- Vehicle length: 3.25 m (128 in), length varies depending upon module configuration.
- Weight in air: 240 kg (530 lbs)
- Maximum operating depth: 600 m (1500 m configurations available)
- Power: 5.2 kWh rechargeable Lithium ion battery. (Second 5.2 kWh or 6.2 kWh battery tray is optional)
- Endurance: Typical mission endurance is 24 hours dependant on speed and sensor configuration, operating environment and mission program.
- Propulsion: Direct drive DC brushless motor to open two bladed propeller
- Velocity range: Up to 2.1 m/s (4 knots) variable over range. Dependant on sensor configuration.
- Control: 3 independent control fins providing yaw, pitch, and roll control. Altitude, depth, yo-yo, and track-line following provided. Optional forward fins available for lateral and pitch control.
- External hook-up: Two connectors, one for shore power, and one for shore data. Alternatively, 802.11G wireless network provided via dorsal fin antenna.
- Casualty circuits: Ground fault, leak and low voltage detection, housing leak detection, all sensors and systems have operational go/no-go fault indicators.
- Navigation: Inertial/DVL navigator, Long base line acoustic, WAAS GPS, P-Code GPS.
- Tracking: Acoustic transponder, acoustic modem, Iridium modem. Shipboard equipment provided with system.
- Communication: Acoustic modem, Iridium, WiFi-2.4 GHz, 100 base-T Ethernet.
- Standard sensors: ADCP/Doppler Velocity Log, Inertial Navigation Unit, Side Scan Sonar, Iridium, GPS, Pressure , Conductivity & Temperature
- Optional payload sensors: User specified, but examples include Dual Frequency 300/900 kHz Side-Scan Sonar (SSS), Video Camera, Electronic Still Camera, Fluorometers, Multi-beam sonar, etc.
- Software: REMUS-VIP GUI based laptop interface for programming, training, documentation, maintenance and troubleshooting
- Emergency relocation: Emergency power system maintains GPS, Iridium, and acoustic transponder in the event of vehicle or CPU failure. Vehicle position and status is automatically transmitted via Iridium at regular intervals.