M528 Dolphin

The M528 Dolphin Light Coastal Motorboat (LCMB), nicknamed the Seahog, is a swift and versatile boat in service with the UNSC Army. They served as the UNSC's smaller counterpart to the Covenant Selkie.

Design details
While the UNSC has extensive fleets of aircraft that can undertake the vast majority of maritime duties, there are still tasks that can be more efficiently and cheaply done with boats and ships. Riverine patrol, boat inspections, and stealth insertion of operatives are all required, and there are times when air support is unreliable or non-existent, making boats like the Dolphin important for the UNSC's fighting resilience.

The Dolphin is small, fast, and versatile, and combines many of the M12 Warthog's most successful design features with adaptations for a waterborne existence. The driver sits in the front somewhat recessed into the hull, with two passenger seats positioned behind it. These can be enclosed with armored doors for protection, however, most boats have them removed to make them more comfortable during hot, humid conditions. A tray with an electromagnetic bed is installed on the boat's aft for the purpose of carrying cargo, or a turret with full 180o coverage. Its speed is attained thanks to a low draft and the use of two Slipcurrent-5 turbo-waterjets. For navigational, scouting, and target-locating purposes, a small SONAR suite is fitted on the keel. A mission bay is also installed nearby, which may carry an enhanced sensor module, decoys, or two mini-torpedoes.

Given its small size, the Dolphin is at its most comfortable and effective when used in calm, shallow waters, such as coastal seas and rivers. The priority placed on crew comfort means that it is remarkably stable, if wet, during higher sea states. The computer-controlled stabilizers and long, retractable fins on the keel keep the roll minimized at all times. It also has thin Zenostium artificial gravity plates to smooth out the ride, especially when jumping over waves.

The Dolphin is usually armed with the M41 Vulcan 12.7mm machine gun, which is effective against hostile fighters and boats it is expected to encounter. When this is insufficient, its modular turret hardpoint is compatible with all weapons used by the Warthog, including the M68 25mm Gauss cannon, the M79 65mm missile launcher, and even the M460 40mm grenade launcher. The UNSC has also seen fit to introduce a launcher for deploying sea mines, depth charges, and micro-torpedoes, for the purpose of attacking submerged targets.