27.954—Fuel system lightning protection.
The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by—
(a)
Direct lightning strikes to areas having a high probability of stroke attachment;
(b)
Swept lightning strokes to areas where swept strokes are highly probable; or
(c)
Corona and streamering at fuel vent outlets.
Code of Federal Regulations
[Amdt. 27-23, 53 FR 34212, Sept. 2, 1988]