Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-300, -400, -500, -600, -700, -700C, -800, -900, and -900ER series airplanes. This AD was prompted by a review of the tail strobe light installation, which revealed that the tail strobe light is not electrically bonded to primary structure of the airplane. This AD requires installing a new tail strobe light housing and a new disconnect bracket, and changing the wire bundles. This AD also requires, for certain airplanes, an inspection to determine if sealant is applied, and corrective actions if necessary. We are issuing this AD to prevent, in case of a direct lightning strike to the tail strobe light, damage to the operation of other critical airplane systems due to electromagnetic coupling and large transient voltages, and damage to the control mechanisms or surfaces due to a fire, which could result in loss of control of the airplane.