Section 25.581 - Lightning protection(a) The airplane must be protected against catastrophic effects from lightning.(b) For metallic components, compliance with paragraph (a) of this section may be shown by- (1) Bonding the components properly to the airframe; or(2) Designing the components so that a strike will not endanger the airplane.(c) For nonmetallic components, compliance with paragraph (a) of this section may be shown by- (1) Designing the components to minimize the effect of a strike; or(2) Incorporating acceptable means of diverting the resulting electrical current so as not to endanger the airplane.Amdt. 25-23, 35 FR 5674, Apr. 8, 1970