Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposal would require repetitive inspections for corrosion and cracking of the pivot hinge pins of the horizontal stabilizer, certain follow-on inspections, and replacement of the hinge pins with new or serviceable pins if necessary. This action is necessary to prevent failure of the outer and inner hinge pins due to corrosion or cracking, which could allow the pins to migrate out of the joint and result in intermittent movement of the horizontal stabilizer structure and consequent loss of controllability of the airplane. This action is intended to address the identified unsafe condition.