Surface effect devices with dynamic boundary layer bleed slots

Claim 1

A GROUND EFFECT VEHICLE HAVING A BODY PROVIDING AN OPEN BOTTOM PLENUM CHAMBER. SAID PLENUM CHAMBER BEING DEFINED BY A DOWNWARDLY FACING, GENERALLY HORIZONTAL WALL PORTION HAVING A MARGINALLY DISPOSED DEPENDING SKIRT MERGING SMOOTHLY THEREWITH, AND BY AN ENTRANCE SKIRT MERGING TO AND THROUGH SAID DOWNWARDLY FACING WALL PORTION, IN WHICH THE ENTRANCE DUCT IS OF RELATIVELY SMALL AREA AS COMPARED TO THE AREA BOUNDED BY SAID SKIRT AND IS JOINED WITH SAID DOWNWARDLY FACING WALL PORTION REMOTE FROM SAID SKIRT, SAID ENTRANCE DUCT HAVING A DOWNWARDLY AND OUTWARDLY FLARED LOWER PORTION MERGING SMOOTHLY WITH SAID DOWNWARDLY FACING WALL PORTION AND RISING UPWARDLY THEREFROM, AND HAVING A CONSTRICTED UPPER PORTION JOINED WITH SAID LOWER PORTION TO BE POSITIONED ABOVE THE LEVEL OF SAID DOWNWARDLY FACING WALL PORTION, FAN MEANS DISPOSED WITHIN THE UPPER PORTION OF SAID ENTRANCE DUCT AND BEING BOUNDED IN CLOSELY SPACED RELATION THEREBY SO THAT AIR IS DISCHARGED SUBSTANTIALLY PERIPHERALLY DOWNWARDLY FROM THE FAN MEANS IN CLOSE ADJACENCY TO THE INNER SURFACE OF THE UPPER PORTION OF SAID ENTRANCE DUCT, SAID LOWER PORTION OF THE ENTRANCE DUCT BEING PROVIDED WITH BLEED OPENINGS THERETHROUGH CONSTRAINING DISCHARGED AIR FLOWING ADJACENT THE INNER SURFACE OF SAID UPPER PORTION OF THE ENTRANCE DUCT TO SPREAD DOWNWARDLY AND OUTWARDLY TO FOLLOW THE INNER SURFACE OF SAID LOWER PORTION FOR DISCHARGE THEREFROM IN CLOSE AND FOLLOWING RELATION TO SAID DOWNWARDLY FACING WALL PORTION FOR ULTIMATE DISCHARGE PREDOMINANTLY PERIPHERALLY DOWNWARDLY FROM SAID PLENUM CHAMBER AT SAID MARGIN THEREOF DEFINED BY SAID SKIRT.