The concept of an inflatable boat is that the rigid wood or aluminum floor will bear down on an inflated keel structure (similar to an inflated torpedo) when locked below the two outboard inflated pontoons. This provides rigidity and longitudinal strength to the vessel, and imparts a vee-shape to the fabric hull which allows for high-speed planing. In this way, a very large and capable vessel may be constructed. It must be stressed that these boats operate under the inflation principle of Volume, not Pressure. The pressures involved are under six pounds per square inch. Inflatables can be powered by one or more outboard motors fitted on the wooden transom. For example, a twenty-five-foot Zodiac(TM) may be powered with twin fifty-five horsepower outboards.
Zodiacs(TM) are manufactured in various shapes and fabric-weights from dinghys to Boston-Whalers(TM) to huge ship-tenders, so are used extensively in tending operations in port and at sea, recreational water skiing, commercial fishing, and in the military, for example, with US Navy SEALS. The size-to-strength ratio of these vessels make them exceptionally portable and valuable in covert operations.
Without the outboard motor it is possible to store up to an eighteen-foot-long boat entirely under one's bed.
The fears associated with inflatable boats are largely unfounded. If punctured, the boat will not sink because the pontoons are compartmented and valved. One may just sail on and make repairs underway. Generally speaking, any patch properly applied to an inflatable boat just makes it stronger. Today's adhesives are so well-formulated that oarlocks for rowing and D-rings for attachment of various objects can be glued to the outer pontoon. Towing rings may be fitted through the very strong transom. Covers, canopies, wave shields and the like are available as options from the various manufacturers.