[en] The Cherenkov nonlinear damping of spiral electromagnetic waves in magnitoactive plasma is investigated. Capture of resonance particles into the potential wave pit, as in the case of the O'Neel problem, is a nonlinear mechanism resulting in oscillations of wave amplitude and restriction of damping. It is shown, that the dependence of the expression for nonlinear damping increment on multipliers of the exp(-αt²) type for the Maxwell particle distribution function results in significantly more rapid damping of spiral wave amplitude oscillations as compared with the Langmuir wave