Airworthiness Directives; Boeing Model 737-100, -200, -200C, - 300, -400, and -500 Series Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This action requires a one-time inspection of the attachment nuts at each end attachment of the elevator tab push rods to measure run-on torque values, and corrective actions, if necessary. This amendment is prompted by reports of excessive high- frequency airframe vibration during flight, with consequent structural damage to the elevator tab, elevator, and stabilizer. The actions specified in this AD are intended to prevent detachment of an elevator tab push rod due to a detached nut at either end attachment of a push rod, which could result in excessive high-frequency airframe vibration during flight; consequent structural damage to the elevator tab, elevator, and horizontal stabilizer; and reduced controllability of the airplane.