Well this may have been covered before. Where I work at the moment all Aircraft even ones that overnight the N1 fans are left to rotate. Is this good,?I know in a Turbo it aint and hence Prop chocks. Also I remmember when I was a Tech in the RAAF in Richmond Sydney and seeing C-5 Galaxies overnight, their CF6 GE s had the N1 Fan chocked to stop rotation in the wind.
Regards
Sheep
P.S. they dont care about it in the Carib