Maritime Tactical Systems (MARTAC) said in May 2026 that its T38 Devil Ray unmanned surface vessel completed a record-setting eight-day, 192-hour fully autonomous mission off the coast of California, marking one of the longest continuous autonomous deployments by a USV in its class.
Inside The 192-Hour Mission
The T38 operated approximately 400 nautical miles offshore for the entire duration of the mission, executing pre-programmed transit, search and station-keeping behaviors without any human-in-the-loop control. The test included a deliberate two-day single-engine operating period—alternating between the boat's twin engines—to evaluate loiter time and endurance under reduced propulsion conditions.
MARTAC said the run delivered a long-duration dataset on autonomy reliability, energy management, communications resilience and mission planning at extended ranges from shore. The T38 belongs to the company's T-class family, which also includes the larger T82 platform.
Why It Matters
The U.S. Navy and partner navies are pushing to field large fleets of unmanned surface vessels for ISR, mine countermeasures, force protection and distributed maritime operations. Recent program announcements have focused on shipyard capacity, autonomy stack maturity and the ability to operate USVs over multi-day missions without persistent human supervision—exactly the regime MARTAC is targeting with the T38.
Earlier this month, the Navy also selected seven medium unmanned surface vessel designs to advance to prototype evaluation, signaling that long-endurance autonomous boats are moving from R&D demos toward fleet-ready platforms.
Looking Ahead
MARTAC said additional endurance and mission-set tests are planned, including expanded payload integration and live exercises with naval customers. The T38 has been used in U.S. Navy exercises and allied demonstrations across the Indo-Pacific and Europe.
The 192-hour milestone is one of the most concrete data points yet on what off-the-shelf USVs can do today in operationally realistic conditions.
Reporting based on coverage from Naval News and MARTAC.