Strong-Coupling Effects in "Dirty" Superfluid $^3He$

The contribution of the strong-coupling effects to the free energy of the "dirty" superfluid $^3He$ is estimated using a simple model. It is shown that the strong-coupling effects are less susceptible to the quasiparticle scattering events in comparison to the weak-coupling counterpart. This supports the conclusion about stabilization of the $B$-phase in aerogel environment at pressures where the $A$-phase takes over in bulk superfluid $^3He$, in accordance with recent experimental observations in zero magnetic field.