The invention discloses a large-flow automatic vent valve for a
supercavitation aircraft. The large-flow automatic vent valve comprises a
valve seat, a first axial vent hole is formed in one end of the
valve seat in the axial direction, and a second axial vent hole is formed in the other end of the
valve seat in the axial direction. A first radial vent hole communicating with the first axial venthole and a second radial vent hole communicating with the second axial vent hole are formed in the valve seat in the radial direction, a valve sleeve sleeves the valve seat, a first annular groove anda second annular groove are formed in the valve sleeve, and the first annular groove communicates with the second annular groove. The distance between the first annular groove and the second annulargroove is smaller than the distance between the first radial vent hole and the second radial vent hole. When the
supercavitation aircraft is launched, the
supercavitation aircraft can be automaticallystarted by means of
inertia. According to the large-flow automatic vent valve for the supercavitation aircraft, the working mode of "fixing a valve element and moving the valve sleeve" is adopted, the situation that the compression amount of an
O ring is suddenly increased is avoided, and the problems of clamping stagnation, "ring
cutting" and the like in the opening process can be solved; and anannular gap between the valve sleeve and the valve element is adopted as a throttling opening, and the large enough ventilation flow can be achieved.