Sponge ballast system for inflatable rafts

Abstract

The system comprised of highly compressed sponge contained in permeable enclosures, which enclosures in turn are secured to the underside of an inflatable raft, which the compressed sponge, upon contact with water, rapidly absorbs water through the openings and quickly expands providing prompt, sufficient weight and ballast for a wet person to climb aboard a raft as light as 5 pounds. The present invention used 20 compressed sponges to achieve such results.

What is claimed is: 
     
         1 . A method of providing supplemental ballast to a lightweight inflatable raft suitable for storage on or in a craft selected from, but not limited to, the group consisting of a kayak, a canoe, a small boat and a small-engine aircraft, said method comprising the steps of:
 a. placing at least one compressed sponge in each of a plurality of water-permeable enclosures; and   b. attaching said enclosures to the underside of a inflatable raft so that, when exposed to water, the sponges increase in weight and become saturated to provide supplemental ballast to the flotation device and stabilize the flotation device due to the increased weight of the saturated sponges to allow a person in the water to self-rescue by mounting the flotation device without the opposite side of the device rising to hamper or prevent entry upon the device; wherein the enclosures allow entry of water to contact the sponges and allow expansion and saturation of the sponges.   
     
     
         2 . The method of claim  1 b. wherein the water-permeable enclosures are attached to the underside of a forward portion of the inflatable raft or circularly configured for a round raft. 
     
     
         3 . The method of claim  1 b. wherein the inflated raft is selected to have a forward portion with a bow at the front of the forward portion, a stern at the back of a rear portion, and a length that is greater than a width of the raft, or circularly configured for a round raft. 
     
     
         4 . The method of  claim 3  wherein the flotation device is inflatable and the water-permeable enclosures are attached to the underside of a forward portion of the flotation device or circularly configured for a round inflatable raft. 
     
     
         5 . The method of claim  1 b. wherein the flotation device is inflatable, and has a floor. 
     
     
         6 . A method of providing supplemental ballast to a water-surface inflatable rescue device capable of carrying one or two human occupants and suitable for storage on or in at least one of a small craft for use on water and a small-engine aircraft, said method comprising:
 a. placing at least one compressed sponge in each of a plurality of water-permeable enclosures; and   b. attaching said enclosures to the underside of the inflatable device so that, when exposed to water, the sponges increase in weight and become saturated to provide supplemental ballast to the flotation device and stabilize the flotation device due to the increased weight of the sponges to allow a user in the water to quickly mount the flotation device without the opposite side of the device rising.