The high-speed SEAL insertion craft that could break your teeth

Wars & Conflicts · Published 9 October 2026 Swipe more like this →

In short: Before the Mark V, Navy SEALs often resorted to taping lawn furniture to boats for transport. The Mark V Special Operations Craft was designed to change that, but its aluminum hull brought a violent side effect: slamming through waves could generate up to 20 Gs of force, causing serious physical injury to operators.

Introduced to the US Navy SEALs in 1995, the Mark V Special Operations Craft (SOC) was developed with extreme speed, moving from program initiation to the delivery of the first vessel in just 18 months. Manufactured by VT Halter Marine Inc, the project reached full operational capability by 1999. While the program was a success in terms of speed and mission capability, the original aluminum monohull design presented significant ergonomic challenges during high-speed maneuvers.

The physics of the aluminum hull meant that impacts with the water were transmitted directly to the occupants. Despite the inclusion of modular shock-mitigation seating, the vessels were capable of generating forces as high as 20 Gs while slamming across waves. These intense impacts resulted in a range of injuries for the crews, including sprained ankles, chipped teeth, and various back, neck, and joint injuries. This physical toll eventually necessitated the vessel's retirement in 2013.

In an attempt to solve these issues, the Office of Naval Research funded an experimental version nicknamed the MAKO. Developed by Hodgdon Yachts and the University of Maine, the MAKO utilized a composite hull made of carbon fiber, foam core, and Kevlar to reduce weight and improve comfort. However, testing did not suggest that a composite structure was the path forward. Instead, the Navy opted to replace the Mark V entirely by 2015 with a new suite of craft, including the Combatant Craft Assault (CCA) and the Combatant Craft Medium (CCM MK1).

Despite its retirement from US service, the Mark V remains a significant platform in maritime history. It was used in early actions of Operation Iraqi Freedom in 2003 to capture offshore oil terminals and has seen international use, such as by the Hellenic Navy and the Kuwait Naval Force. Even in the civilian sector, the craft has found a new life, with the founder of Oculus VR, Palmer Luckey, acquiring a unit in 2019.

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