Multi-layer ram air parachute canopy
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorJon T. Matsuo
Life of this patent
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Abstract
Maximum lifting force is achieved in a dome-shaped parachute by fabricating he canopy of upper and lower spaced canopy membranes. A plurality of circumferentially spaced, radially disposed, flexible rib sections are connected between the canopy membranes to form a plurality of ram air cells, each cell having a ram air inlet port at the canopy hem, and a ram air outlet port at a central vent at the canopy apex. The rib sections can be provided with porous sections to equalize the ram air pressure between adjacent cells. The bottom canopy wall in each ram air cell may also be provided with a porous section for admitting the positive air beneath the canopy into each cell. A pull down vent line can be connected to the canopy apex for changing the camber or angle of attack, and therefor the parachute drag.
Claims4
A parachute for variably decelerating a connected load comprising:
- a flexible, dome-shaped canopy having upper and lower circular, concentric canopy membranes,
- each said membrane having a hem around the outer edge thereof and an apex with an air vent at the center thereof, said air vents being of equal size;
- a plurality of suspension lines connected between said canopy hems and said load;
- a plurality of radially extending and circumferentially spaced ribs connecting said upper and lower membranes in spaced relation thereto and forming a plurality of airfoil-shaped ram air cells therebetween;
- each said cell having a ram air inlet port at said hem and a ram air exhaust port at said apex air vents and diminishing in cross-sectional area from said hem to said apex;
- means for simultaneously varying the airflow through and the camber of said airfoil-shaped ram air cells attached to said apex;
- each of said ribs having a porous section made of a mesh-like material therein for the passage of air therebetween to equalize the air pressure between adjacent cells;
- said lower canopy membrane having a porous section at each said airfoil-shaped ram air cell to allow the passage of air pressure under the canopy to enter said airfoil-shaped ram air cell;
- whereby a maximum retardation force on said parachute is achieved during descent.
Dependencies are inferred from the claim text.