The US National Transportation Safety Board (NTSB) issued six recommendations to improve the safety standards of uncrewed surface vessels (USVs) following its investigation of a 2024 vessel collision on Lake Erie.
The incident
On Aug. 10, 2024, a National Oceanic and Atmospheric Administration Great Lakes Environmental Research Lab SeaTrac SP-48 uncrewed surface vessel and a privately-owned Prestige 450 Flybridge recreational vessel collided near Monroe, Michigan.
The USV became entangled in the recreational vessel’s starboard propeller pod. Both vessels were towed together to a nearby marina and later separated.
One minor injury was reported as a result of the collision. The USV was considered a total constructive loss, with an estimated value of $186,000. Damage to the recreational vessel was estimated at $100,000.
The investigation
The NTSB found that the 15.7-foot-long USV was difficult for other mariners to see because only about a foot of its hull was visible above the water. Additionally, it is unlikely that the USV would be perceived electronically (radar or automatic identification system) by the recreational vessels typically operating in the area.
At the time of the collision, NOAA was operating the USV in “adapted hold” mode, which allowed the vessel to automatically return to preset waypoints if it drifted beyond a 150-foot radius established by its remote pilot. The pilot passively monitored the vessel from ashore while the system maintained its waypoints. The NTSB determined that this level of monitoring was insufficient for safe operation in an area frequented by recreational vessels.
The investigation also found that, at the time of the collision, there were no industry-wide standards specifically addressing the perceptibility, collision-avoidance capabilities and navigational safety of USVs operating in U.S. inland and territorial waters.
“As USVs become more commonplace in U.S. waterways, it is critical for the Coast Guard to begin to set standards and policies for these vessels,” the report said.
Recommendations
To the US Coast Guard:
- Develop and promulgate a national framework of perceptibility, collision avoidance capability, and navigational safety standards for uncrewed surface vessels. (M-26-03)
- Incorporate perceptibility, collision avoidance capability, and navigational safety standards for uncrewed surface vessels into regulations. (M-26-04)
To the National Oceanic and Atmospheric Administration:
- Revise your “Uncrewed Marine Systems Manual” to ensure all uncrewed surface vessels are perceptible to vessel traffic given the vessel’s area of operation. (M-26-05)
- Incorporate into your “Uncrewed Marine Systems Manual” a requirement for testing of uncrewed surface vessels you operate to ensure adequate perceptibility to operators of other vessels typically in the uncrewed surface vessel’s area of operation. (M-26-06)
- Require your uncrewed surface vessels to be monitored at a level commensurate with the uncrewed surface vessel’s actual level of autonomy, factoring the vessel’s area and mode of operation. (M 26 07)
To SeaTrac Systems, Inc.:
- Modify the design of the SP-48 uncrewed surface vessel to further enhance its perceptibility as practicable given the nature of the uncrewed surface vessel’s work and area of operation. (M-26-08)
Download the report: