  The supersonic propeller spindown of a neutron star moving in a strong
stellar wind of its massive companion is discussed. I show that the supersonic
propeller model presented by Davies & Pringle (1981}) is self-consistent if the
strength of the stellar wind of the normal companion is \dot{M}_{\rm c} \la 2.2
10^{18} (M_{\rm ns}/M_{\sun}) V_8 g/s. Under these conditions the model can be
used for the interpretation of the long-period pulsars in Be/X-ray transients.
The spin history of the neutron star in the long period Be/X-ray transient
A0535+26 is considered.
