Sailors who man speedboats used in Navy SEAL operations are in danger of traumatic brain injuries from repeatedly slamming into waves because the vessels don’t have systems that alleviate shock, according to a Pentagon watchdog agency.
The boats also lack a monitoring system to measure craft and crew shock and whole-body vibration, among other deficiencies, the Defense Department inspector general said in a March 30 report.
As a result, crew members are at serious risk for lower back and neck injuries as well as chronic pain and head injuries, the report stated. It also noted that service members are exposed to blast forces when firing heavy weapons.
“Repetitive impacts significantly degrade immediate performance and can result in long-lasting medical problems,” the IG said. Traumatic brain injuries also “may result in a degradation of the health of the force and its long-term sustainability,” the report added.
The IG report cited a U.S. Special Operations Command directive that said traumatic brain injuries can result from acute or repetitive blast exposure and acceleration and deceleration forces.
The potential for injuries can be heightened by body armor, helmets and night vision goggles, and a boat console design that forces vessel operators to stand in a slouched forward position to reach controls, the IG found.
A Navy hospital corpsman conducts a traumatic brain injury assessment on another sailor at Camp Lejeune, N.C., on Jan. 14, 2026. Sailors operating speedboats in Navy SEAL missions face heightened risk for lifelong health issues, including TBIs, that could undermine overall force readiness, according to a Defense Department watchdog. (T. T. Parish/Defense Health Agency)
At issue are combatant craft assault boats that travel at speeds of up to nearly 70 miles per hour. The vessels are crewed by a contingent of about 800 active-duty personnel and as many as 125 reservist special warfare combatant craft crewmen.
Those sailors are trained in maritime direct-action operations and special reconnaissance as well as insertion and extraction of special operations units, according to a report last year from the Military Health System’s Traumatic Brain Injury Center of Excellence.
The boats’ hulls and equipment are designed to withstand a gravitational force, or G-force, of up to 6 with the vessel’s suspension seats able to mitigate G-force impacts as high as 5, according to the Military Health System report issued in February 2025.
But “slamming induced impacts to high-speed boats can exceed 20 G-force,” it stated.
A G-force of 1 is defined as the acceleration of an object due to the force of gravity on Earth. Decreased brain oxygenation can occur with exposure to G-forces as low as 3 to 4, according to the MHS.
The MHS report cited a September 2022 internet-based study of retired special warfare combatant craft crewmen that showed 33% had experienced a temporary loss of consciousness due to wave-slamming.
Also, 70% of respondents said on-the-job injuries, including those to their back and neck, had impaired their job performance, according to the MHS report.
The Defense Department IG wants Naval Special Warfare Command to review and validate five potential solutions, including installing head and neck support devices and adjustable seating as identified in a January 2024 Naval Special Warfare Group 4 report.
The Navy also should develop an action plan to implement those solutions or identify alternatives, the agency said. The command agreed with the recommendations but did not offer comment.
The recommendations are resolved but remain open until the DOD IG verifies that the command has validated the proposed solutions and developed a plan to implement them or suitable alternatives.
