Ground effect machines having flexible skirts

Claim 1

A VEHICLE FOR LIFTING AND TRANSPORTING LOADS SUPPORTED ABOVE AND CLEAR OF THE SURFACE BY MEANS OF AT LEAST ONE AIR CUSHION, COMPRISING: A BASE MEMBER, A SKIRT OF SUBSTANTIALLY FLUID TIGHT FLEXIBLE MATERIAL EXTENDING DOWNWARDLY FROM THE PERIPHERY OF SAID BASE AND BEING ATTACHED THERETO IN A SUBSTANTIALLY FLUID TIGHT RELATIONSHIP TO FORM AT LEAST THE UPPER PART OF THE OUTSIDE BOUNDARY OF AN AIR CUSHION UNDER SAID BASE, THE FREE PERIPHERAL EDGE OF SAID SKIRT BEING FLACCID AND DEFINING A CROSS SECTIONAL AREA LESS THAN THE CROSS SECTIONAL AREA OF THE BASE MEMBER, THE SKIRT TAPERING INWARDLY FROM THE POINT OF ATTACHMENT TO THE BASE TO THE FREE EDGE THEREOF, A SERIES OF PERIPHERAL NOZZLES HAVING EXIT ORIFICES SPACED DOWNWARDLY FROM THE BASE AND TERMINATING ADJACENT THE INNER WALL OF THE SKIRT AND BEING INWARDLY DIRECTED TO FORM AND MAINTAIN THE AIR CUSHION WITHIN THE SKIRT, THE INTERNAL PRESSURE OF THE AIR CUSHION HAVING A DOWNWARD COMPONENT ACTING AGAINST THE INWARDLY TAPERED SKIRT TO MAINTAIN THE SKIRT IN THE EXTENDED POSITION THEREOF, THE FLACCID FREE PERIPHERAL EDGE OF THE SKIRT PERMITTING THE SKIRT TO FOLD LOCALLY TO PASS OVER AN OBSTACLE WITHOUT SUBSTANTIAL LOSS OF PRESSURE IN THE AIR CUSHION.