Underwater mine countermeasure warfare system

In combination with an air cushion vehicle having a platform, means mounted on the platform for discharging air into an air chamber located beneath the platform, an air retaining skirt attached to and surrounding the platform for retaining a cushion of air in the air chamber at sufficient pressure to support the vehicle above the surface on which it normally rests, and means mounted on the platform for propelling the vehicle in a given direction when the vehicle is supported by the cushion of air, an operating tool retraction apparatus carried by the vehicle for deploying and retracting the operating tool while normally suspended beneath the platform of the vehicle and occasionally for disposing the tool on the upper surface of the vehicle platform, said apparatus comprising:

• A. an operating tool,
• B. retracting means mounted on the upper surface of the platform for normally suspending said tool beneath the platform and for raising and lowering said tool between a storage position adjacent the lower surface of the platform and an operative position spaced beneath said lower surface of the platform, and for raising said tool through an access opening in the platform to the upper surface thereof for manual access to said tool, and
• C. pressure boundary means mounted on the platform over said access opening for alternately normally providing an air seal between the upper and lower surfaces of the platform when said tool is disposed beneath the platform in either of said storage or operative positions, and exposing said access opening in the platform through which said tool passes when being raised to said upper surface of the platform for manual access to said tool,
• whereby said tool can be raised or lowered between said storage and operative positions and suspended in either of said positions while maintaining sufficient air pressure in said air chamber to permit said vehicle to remain supported on said air cushion.