Need some help I have a DA50 on my toc yac. I just got the DL50 back from desart aircraft for repairs I flown twice on the second flight the prop and hub came of it looks as if no lock tight was used it sheard of the key way and had to dead stick plane has damage but can be repaired.The question I have sould you use lock tight and how do you get it tight with the motor tring to pin. I could pull spark plug and put somethink in the hole to keep from spinnig but dont want to hurt the piston. I just dont know why the thing came off to begin with. I just dont think they got it tight before they sent it back. Thanks for the help. RoadRunner