With my 28 yrs of aircraft maintenance involvement I can only agree with nodrama, that report is surprisingly ambiguous - AAIB was always a first-class source of information. Using term "solenoid valve" for a hydraulic system component is softly said, misleading. (except in case there is truly an electromagnetic valve involved - in that case I will have to bury myself )
nodrama, can you comment or confirm that torque applied to castellated nut, that holds duplex bearing in place on control rod, has no effect on the bearing itself i.e. that overtorquing it will not "squeeze" balls between inner and outer race, but "only" overload the rod-threads?
Is duplex bearing actually made of two completelly separate bearings, turned one against the other, or is it one component? From the Fig. 4 in AAIB S2/2018 it seems there are two inner races, but one outer race. Such design implies that nut torque could have an effect on bearing friction? (if there is a gap between inner races-depends on design) Please help clarifying this, if you can!
hoistop