From DefenseImagery.mil, an artist's concept of the Bell Aerospace Textron Mine Sweeper Hunter (MSH). In Fiscal Year 1984, the US Navy embarked upon a program to construct 17 minesweeper hunters of some 470 tons displacement that utilized surface-effect-ship and glass-reinforced plastic hull structure technology proven in Sweden. The MSH-01 class was intended to supplement the Avenger-class mine countermeasures ship (MCM-01), but was considered a failure and cancelled on August 25, 1986.
According to DefenseImagery.mil:
Source: http://www.defenseimagery.mil/imagery.html#a=search&s=MSH&guid=9ee97b499f4f91d0e62eb6fc156046dabb190cf3
More information: http://www.globalsecurity.org/military/systems/ship/msh-1.htm
According to DefenseImagery.mil:
An artist's concept of a minesweeper hunter (MSH) underway. The MSH is a new class of minesweeper using an air cushion to reduce the contact of the hull with the water surface, thus making it less susceptible to underwater shock from mine explosions. The air cushion also makes it less likely that today's sophisticated mines will be triggered before they can be detected and neutralized.
Source: http://www.defenseimagery.mil/imagery.html#a=search&s=MSH&guid=9ee97b499f4f91d0e62eb6fc156046dabb190cf3
More information: http://www.globalsecurity.org/military/systems/ship/msh-1.htm