Abstract: A mechanical component attachment safety system is disclosed wherein a position of a blcoking rod is controlled by an over-center lever assembly having a drive lever connected to the blocking rod by a cable actuating system and a link rod. Movement of the drive lever between its over-center positions causes the blocking rod to extend or retract, accordingly. When extended, the blocking rod will prevent closure of a cowl or protective panel and when retracted, will permit closure of the panel or cowl. The drive lever is engaged by a fastener attaching a mechanical component to a frame so as to be retained in a position in which the blocking rod is retracted. If the mechanical component is not properly attached, the fastener will not engage the drive lever, which is biased to its opposite over-center position so as to cause the extension of the blocking rod and prevent closure of the panel or cowl.