Key Points – In a significant advancement for naval warfare, the U.S. Navy’s Virginia-class fast-attack submarine, USS Delaware (SSN 791), has successfully executed a pioneering unmanned mission within the U.S. European Command (EUCOM) area of operations.
According to a May 30, 2025, announcement by the U.S. Commander of Submarine Forces, the operation featured the Yellow Moray Unmanned Underwater Vehicle (UUV).
This customized REMUS 600 UUV is engineered for diverse underwater tasks, including mine countermeasures, surveillance, reconnaissance, and hydrographic surveys.
This mission represents the first-ever forward-deployed launch and recovery of a UUV through a submarine’s torpedo tube to fulfill a tactical objective, heralding a major breakthrough in autonomous capabilities for the submarine force.
Validating Autonomous Undersea Operations
The groundbreaking mission comprised three distinct autonomous sorties, each lasting between six and ten hours, all conducted by the same Yellow Moray UUV. Critically, all launch and recovery procedures were performed via the USS Delaware’s torpedo tubes while the submarine remained submerged, eliminating the need for divers. This successful demonstration validated the system’s reliability and operational effectiveness under real-world conditions.
It powerfully underscores the strategic advantages of integrating robotic platforms into conventional submarine operations, enabling novel approaches to subsea and seabed warfare (SSW) while markedly reducing risks to naval personnel.
USS Delaware (SSN 791): A Platform for Innovation
Commissioned in April 2020, the USS Delaware is the 18th Virginia-class submarine and a Block III variant. This formidable platform measures 115 meters (377 ft) in length, with a beam of 10.3 meters (34 ft), and displaces approximately 7,800 tonnes when submerged. Powered by an S9G nuclear reactor and a pump-jet propulsor, it can achieve submerged speeds exceeding 46 km/h (25+ knots) and operate at depths greater than 240 meters (800+ ft).
The submarine is heavily armed with 12 vertical launch system (VLS) tubes for Tomahawk cruise missiles and four 533mm torpedo tubes capable of launching Mk 48 ADCAP torpedoes. Its advanced sensor suite, featuring the AN/BQQ-10 sonar and a Large Aperture Bow (LAB) array, provides superior undersea detection. The USS Delaware is also optimized for special operations, equipped with reconfigurable payload spaces and compatibility with dry deck shelters.
The Yellow Moray UUV: Extending Submarine Reach
The Yellow Moray, a mission-specific adaptation of the REMUS 600 UUV developed by HII’s Hydroid division, is designed for long-duration, high-endurance missions at depths up to 600 meters (1,968 ft). The UUV is 3.25 meters (10.7 ft) long, has a diameter of 0.32 meters (12.6 in), and weighs around 240 kg (530 lbs). Its modular architecture allows for a variety of mission payloads, such as synthetic aperture sonar, side-scan sonar, CTD (Conductivity, Temperature, Depth) sensors, Doppler Velocity Logs (DVL), and inertial navigation systems. The Yellow Moray can operate autonomously in GPS-denied environments and navigate complex routes in both shallow and deep-water conditions.
Key missions for the Yellow Moray include seabed mapping, mine countermeasures, hydrographic reconnaissance, and monitoring of undersea infrastructure. It is also adept at supporting intelligence, surveillance, and reconnaissance (ISR) operations in high-risk or denied areas where traditional naval assets might face unacceptable threats. The data provided by the UUV offers operational commanders valuable environmental and tactical intelligence, facilitating informed decision-making and more effective battlespace preparation.
Strategic Implications for the U.S. Submarine Force
The operational deployment of UUVs like the Yellow Moray signifies a transformative enhancement of the U.S. Submarine Force’s mission capabilities. These autonomous systems enable submarines to project influence and gather intelligence far beyond manned operational limits.
They can conduct detailed surveys and reconnaissance in contested or hazardous maritime environments without directly exposing the host submarine or its crew to danger. Furthermore, UUVs increase the tempo and persistence of undersea operations, as they can be rapidly redeployed for subsequent missions, often without requiring maintenance between sorties. The ability to launch and recover UUVs via torpedo tubes also preserves the submarine’s stealth and operational security by eliminating the need to surface or deploy divers.
Vice Admiral Rob Gaucher, Commander of Submarine Forces, underscored the strategic benefits, stating that integrating autonomous systems aboard submarines “reduces risk to personnel and enables distributed sensing in complex environments.” He affirmed the Navy’s commitment to expanding these capabilities across the fleet, ensuring future attack submarines are equipped not only with potent weaponry and sensors but also with unmanned systems that act as force multipliers.
Overcoming Challenges: Innovation in Action
The success of this mission also highlighted the adaptability and innovative spirit of the Submarine Force and UUV Group 1 personnel. Following an initial setback during trials in a Norwegian fjord in February, where a UUV failed to recover due to damage discovered post-launch, the system was swiftly returned to the U.S. for urgent repairs. SUBFOR then rapidly redeployed the UUV back to the European theater. The USS Delaware subsequently performed a successful expeditionary reload and executed multiple autonomous missions, including the first-ever pierside diver-assisted torpedo tube UUV loading operation in Norway.
(July 9, 2018) – Multi-national Special Operations Forces (SOF) participate in a submarine insertion exercise with the fast-attack submarine USS Hawaii (SSN 776) and combat rubber raiding craft off the coast of Oahu, Hawaii during Rim of the Pacific (RIMPAC) exercise, July 9. Twenty-five nations, 46 ships and five submarines, about 200 aircraft, and 25,000 personnel are participating in RIMPAC from June 27 to Aug. 2 in and around the Hawaiian Islands and Southern California. The world’s largest international maritime exercise, RIMPAC provides a unique training opportunity while fostering and sustaining cooperative relationships among participants critical to ensuring the safety of sea lanes and security of the world’s oceans. RIMPAC 2018 is the 26th exercise in the series that began in 1971.` (U.S. Navy photo by Mass Communication Specialist 1st Class Daniel Hinton)
U.S. Navy Virginia-Class Submarine.
Western Australia, Australia (Feb. 25, 2025) The Virginia-class fast-attack submarine USS Minnesota (SSN 783) prepares to moor at HMAS Stirling, Western Australia, Australia, Feb. 25, 2025. Minnesota arrived in Western Australia kicking off the first of two planned U.S. fast-attack submarine visits to HMAS Stirling in 2025. Minnesota is currently on deployment supporting the U.S. 7th Fleet, the U.S. Navy’s largest forward-deployed numbered fleet, operating with allies and partners in preserving a free and open Indo-Pacific region. (U.S. Navy photo by Lt. James Caliva)
This operational triumph confirms the readiness of submarine-launched UUVs for a broad spectrum of critical undersea warfare missions. As the U.S. Navy continues its push towards greater autonomy within its undersea forces, the Yellow Moray’s deployment from the USS Delaware marks a pivotal milestone in the evolution of 21st-century naval combat.
It paves the way for a future where manned and unmanned assets collaborate seamlessly to ensure enduring undersea dominance.
