Safety device for helicopters and similar machines having rotors.

SHORT The device includes an inflatable envelope attached under lower Lacoque of the helicopter by marrying in its partiesupérieure, the entire face of the lower hull del'hélicoptère before and in the use position and inflation, a trapezoidal shape very high volume overflowing very largementdu volume defined by the helicopter by increasing the desustentation polygon, said envelope being provided on its sides withcompounds anti-buckling reinforcing means, and means limiteurset controllers pressure inside.