During a recent US naval test off California’s coast last month, intended to demonstrate the Pentagon’s leading autonomous drone boats, one vessel unexpectedly experienced a stall. While technicians tried to resolve a software issue, a second drone vessel collided with the stationary boat’s starboard side, vaulted over its deck, and submerged back into the water—footage of which was obtained by Reuters.
This incident, involving two vessels developed by American defense companies Saronic and BlackSea Technologies, remained unreported until now. It marks a series of recent hurdles in the Pentagon’s efforts to establish a fleet of autonomous maritime vessels, according to a dozen sources familiar with the project.
Earlier, during a separate Navy trial, the captain of a support boat was thrown into the water when an autonomous BlackSea vessel it was towing suddenly accelerated, causing the support ship to flip. The captain was rescued and declined medical treatment. First reported by Defence Scoop, both mishaps resulted from a mix of software failures and human mistakes, including communication breakdowns between onboard systems and external control software, according to an insider who requested anonymity.
The Navy, Saronic, and BlackSea declined to comment on these incidents. The videos capturing the drone collision were verified by two Reuters sources, showing terrain aligns with images of the Global Autonomous Reconnaissance Craft (GARC), confirming the vessels’ identities.
Faced with the significant role maritime drones play in Ukraine’s conflict, U.S. military leaders emphasize the need for swarms of autonomous aerial and sea drones to hinder potential Chinese advances through the Taiwan Strait. Taiwan has initiated its own purchases of maritime drones for defense.
Ukraine’s drones often resemble fast speedboats without seats, equipped with weapons, explosives, and surveillance gear. Many are remotely operated and cost approximately $250,000 each, serving as “kamikaze” weapons that have effectively neutralized Russia’s Black Sea Fleet.
In contrast, the U.S. aims to develop an autonomous naval fleet capable of functioning in coordinated swarms without human commands—an ambitious and pricier goal, with individual vessels costing several million dollars.
These recent failures underline the challenges of deploying cutting-edge autonomous systems, said Bryan Clark of the Hudson Institute. The Navy will need to adjust its tactics to better understand what these systems can and cannot do.
However, the issues extend beyond technology. The Navy’s autonomous drone program has also been disrupted by the dismissal of its top commander, and a senior Pentagon official expressed concerns about the program during a candid meeting with Navy officials last month, Reuters reports.
Since that incident, the Pentagon’s Defense Innovation Unit (DIU)—which procured the technology used in the tests—has paused a nearly $20 million contract with L3Harris, one of the companies providing autonomous software for the vessels. The Pentagon has not issued details on the cause of the accidents or the reasons for the contract suspension.
A Pentagon spokesperson described the drone testing as part of a “competitive and iterative process” involving industry. L3Harris did not comment directly but reaffirmed its commitment to the safety and integrity of their autonomous control products.
In 2023, to accelerate its drone initiatives, the Pentagon launched the $1 billion Replicator program, aiming to purchase thousands of aerial and maritime drones along with their control software. The first systems from this initiative are expected to be announced this month.
The Navy has invested at least $160 million in BlackSea, which produces dozens of its GARC boats monthly. Saronic, recently valued at $4 billion in funding backed by Andreessen Horowitz and 8VC, has developed the Corsair sea drone but hasn’t secured any major contracts yet, though it has earned over $20 million from prototype deals.
Naval leaders emphasize that these systems will play a vital role in future warfare by extending fleet reach, enhancing situational awareness, and boosting combat effectiveness, said acting Chief of Naval Operations Jim Kilby during a visit to BlackSea’s facility in June.
Since the Biden administration took office, naval efforts to deploy autonomous drones—previously a priority for President Trump—have faced skepticism. The Navy’s key drone boat program was praised earlier this year, but subsequent internal reviews and leadership changes have cast doubt on its trajectory.
The unit managing unmanned systems is now under review, following the resignation of Rear Admiral Kevin Smith over leadership issues. In a recent high-level meeting, Defense Secretary Steven Feinberg expressed doubts about some of the Navy’s autonomous vessel capabilities and questioned their value for money.
The Navy maintains its commitment to these projects, stating the Program Executive Office Unmanned and Small Combatants (PEO USC) remains dedicated to acquiring and modernizing unmanned maritime systems. Meanwhile, the service is exploring bids for new medium and large vessels capable of carrying weapons, surveillance gear, and cargo, signaling plans to expand autonomous fleet components.
Experts like TX Hammes note that the Navy is navigating uncharted waters, trying to overhaul decades of tradition at a swift pace—comparable to a large shipyard used to building massive ships taking years, now tasked with rapid development of autonomous systems.
